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Organic Safety Manual 12th Edition, created 22.09.2014 by Simon Woodward
ORGANIC CHEMISTRY RESEARCH
GENERAL SAFETY MANUAL
No one may work in these laboratories unless they have read and understood these notes, and agree
to abide by the general recommendations, protocols and prohibitions contained therein.
The Safety Form at the end of this manual must be completed and countersigned by the
research supervisor, and given to the Section Safety Officer (Prof. Simon Woodward) before
starting work.
2
CONTENTS
Page
1
A.
SUMMARY OF SAFETY RULES
B.
SAFETY LEGISLATION
1. The Health and Safety at Work Act
2. Control of Substances Hazardous to Health
2
2
2
C.
RISK ASSESSMENTS
1. 1st–3rd Year Undergraduate Laboratory Work
2. 4th Year Undergraduate Laboratory Work (Projects)
3. Postgraduate Research Assistants
4. Members of Staff
5. Making Risk Assessments
6. The COSHH Database
3
3
3
3
5
5
9
D.
EMERGENCY PROCEDURES
1. The Emergency Alarm
2. Types of Fire and Fire-fighting
3. Safety Stations
4. Breathing Apparatus
5. Basic First Aid
6. Accident Reporting
10
10
11
12
12
13
16
E.
RULES GOVERNING USE OF THE CHEMISTRY BUILDING
1. Normal Working Hours
2. Outside of Normal Working Hours
3. Building Services
4. Overnight or Unattended Experiments
16
16
17
17
18
F.
SAFETY IN THE LABORATORIES
1. Good Chemical Laboratory Practice
2. Additional Safety Measures
3. Preventing Accidents
4. Common Causes of Personal Injury
5. Tidyness
6. Communal Facilities
18
18
19
20
23
25
26
G.
CHEMICALS AND SAFETY
1. General Considerations
2. Chemical Toxicity
3. Laboratory Hazards Boards
4. Gas Cylinders
5. Liquid Nitrogen
6. Detoxification and Disposal
28
28
28
32
32
33
34
H.
BIBLIOGRAPHY
39
I.
EMERGENCY TELEPHONE NUMBERS
inside back cover
1
A. SUMMARY OF SAFETY RULES
1.
Safety glasses must be worn at all times in the laboratories. Laboratory coats are essential
wear for Organic experimental work.
Bare arms and bare legs are not allowed for
experimental work.
2.
In laboratories , note the position of fire extinguishers, fire blankets, etc.
3.
No one may carry out experimental work whilst alone in the laboratories.
4.
COSHH assessments must be completed before preparative experiments are attempted.
5.
Put compound hazards on whiteboards outside labs on a daily basis. Use red pen for stench
chemicals
6.
Eating, drinking, smoking, or the use of radios, cassette players etc. are forbidden.
7.
Overnight or unattended experiments must carry a completed overnight card.
Risk
experiments must have been independently checked, and the card countersigned by the
research supervisor or his/her nominee.
8.
All unauthorized experiments are expressly forbidden.
9.
All persons present in the Department out of hours (08.30–18.00, Monday–Friday) must sign
the 'out-of-hours' register.
10. The fire alarm is tested on Monday mornings at about 8.55 am. Unless the alarm is not
switched off after about 30 seconds, you need not do anything. At all other times if the alarm
goes off, evacuate the building in an orderly fashion immediately.
These rules are in place for your own protection. Contravention of any rule is regarded as a
serious offence, and disciplinary proceedings will follow.
2
B. SAFETY LEGISLATION
All work in the Chemistry Department is subject to two Acts of Parliament. Compliance with this
legislation is monitored by the Health and Safety Executive (the HSE) who have a large number of
inspectors spread around the various regions of the country. An HSE Inspector has wide-ranging
powers; these include the ability to shut-down a place of work or to bring a criminal prosecution for
infringements of the Acts. We are all therefore obliged to obey both the terms and spirit of each
Act.
1. The Health and Safety at Work Act (1974)
This Act places duties on all employed persons to take reasonable care of their own health and
safety and the health and safety of others who may be affected by what they do, or omit to do. In
addition every employee has a duty to co-operate with their employer and must not intentionally or
recklessly interfere with or misuse anything provided in the interest of health, safety, or welfare.
Thus, everyone bears a statutory responsibility for taking due care in the laboratory, for observing
appropriate precautions, and taking necessary preventative measures when carrying out operations.
Remember that there is always an element of danger present in a laboratory. You will be in
frequent contact with potentially dangerous materials or equipment, careless or improper use of
which can result in a serious accident, even physical injury. In research work it is particularly
important to try and anticipate problems; make sure that you are always properly briefed. Do your
homework! If in doubt – ask!
2. Control of Substances Hazardous to Health Regulations (COSHH, 1990)
Basically, these Regulations redefine the way in which toxic materials can be handled at work, and
it is a criminal offence for any work using such materials to proceed without a proper assessment
first having been made. The object of an assessment is the elimination or adequate control of risks
to health. Risk is a function of both hazard (potential of a substance to impair health) and
exposure potential (extent to which a substance may enter, or come into contact with, the body).
Broadly speaking:
RISK = HAZARD x EXPOSURE POTENTIAL
3
C. RISK ASSESSMENTS
1. 1st-3rd Year Undergraduate Laboratory Work (Set Experiments)
These students obtain all of their essential information from the laboratory manuals with which
they are supplied. The experiments have been assessed by the member of staff in charge of that
laboratory, and notable risks and the precautions to be taken are recorded in the individual
experiments in the student's manual. No separate assessment is necessary since the assessment is
implicit in the experimental detail given to the student in the manual.
●
However, Demonstrators must save undergraduates from the foolishness of their own actions
by constant, careful surveillance of the teaching laboratory and by rendering practical help
and assistance whenever necessary.
2. 4th Year Undergraduate Laboratory Work (Projects)
Each of these experiments must be separately assessed using the standard COSHH assessment grid.
Project students should be treated as in 3(a) - i.e. as inexperienced research assistants, and the
project supervisor (or nominee) must check and sign the assessment before the student attempts the
experiment. High risk experiments [i.e. Category A, see 3(a) below] must be directly
supervised. Postgraduates should keep project students under constant and careful surveillance
and give help when necessary; the project supervisor (or deputy) will be present in the laboratory
only for limited periods of time. Undergraduates are not allowed to work when the laboratory is
not manned by postgraduates.
3. Postgraduate Research Assistants
●
Failure to carry out COSHH assessments will be treated as a serious offence, and will lead to
immediate suspension from laboratory work. This applies to all personnel, whatever their
status.
(a) First Year Postgraduates
Although the B.Sc./M.Sci. degrees (or equivalent) indicate a recognized qualification in chemistry,
new postgraduates are nevertheless relatively inexperienced in experimental work. They are
expected to do their own assessments which the supervisor (or nominee) should check and sign
4
before the experiments are started. This procedure should be followed normally for the first 3
months (e.g. conveniently from 1st Oct to 31st Dec) or until such time as the supervisor decides is
necessary. Procedure 3(b) is then followed. However, assessments also place experiments into
one of four categories A-D, depending on the risk; these categories have the following meanings: A
B
C
This activity must be directly supervised.
The supervisor's advice and approval must be sought before the task is started.
The work involves risks requiring careful attention to the safety related aspects of it. The
worker has been trained in the task and has demonstrated competence.
D
Tasks in this category carry no undue risks. (In preparative work, very few reactions fall
into this category).
Category A is for experimental work that potentially has a high risk because one (or more) of the
reactants is especially hazardous, or the procedure itself may be hazardous. This includes:
●
●
All work listed under the Standard Protocols section of the COSHH grid (e.g. Pyrophorics,
Hydrogenation, Peroxides, Ozone, etc.)
Any work involving the use of carcinogenic materials (e.g. alkylating agents, benzene, etc.).
●
●
●
Any work involving the use of inorganic cyanides or other highly toxic substances.
Materials listed as explosives as well as some powerful oxidising substances.
Reactions run in sealed or pressurized systems.
If Category A is pertinent, then your supervisor must arrange for you to be trained in the procedure
under direct supervision. Information can be found on the departmental website and you must
complete your Record of Safety Competence and have it signed before you start the experiment.
Once you have been trained in the appropriate method to your supervisor's satisfaction, then for that
type of work in future the Risk Category may be downgraded to Category B. Separate training is
necessary for each type of circumstance in Category A before it may be downgraded to Category
B for future work (i.e. training in handling pyrophorics does not equip you to handle liquid
ammonia safely!). However, once the research project is well underway, most of your work will be
in Risk Categories B or C.
●
Other, more experienced personnel in the laboratory should take it upon themselves to keep
an eye on new postgraduate students and give help and advice when necessary. It is
recognized that the "supervision" by the research advisor can never be constant.
5
The research supervisor is expected to check research coworkers COSHH assessments
periodically and sign the laboratory notebook to indicate that the supervisor is aware these
experiments are being conducted.
(b) Other Postgraduates and Post-doctoral Assistants
Each experiment must be properly assessed and the assessment recorded before the experiment is
attempted. The research supervisor is expected to check these assessments periodically and sign
the laboratory notebook to indicate that such a check has been made. Clearly, if the supervisor
feels that the assessment is deficient in any way he should discuss the matter with the person
concerned and any problems should be rectified. Category A tasks [see Section 3(a)] may only be
performed without direct supervision if you have already received training in that task and are
deemed competent.
●
Even postdoctoral assistants cannot be expected to know everything; do not be too proud to
seek out expert help!
4. Members of Staff
(a) Members of the academic or technical staff engaged on non-routine experimental work are also
expected to carry out the full assessment procedure.
(b) Members of the technical staff engaged on routine duties (i.e. nmr services, mass spectrometry
and stores personnel) which involve the handling of chemicals should each have received a
copy of an assessment of their duties. Separate assessments of their daily tasks
are
not
necessary, but any change in their job routine, or any problems, should be reported to the
Safety Officer so that the appropriate modifications to the assessment can be made.
5. Making Risk Assessments
●
All persons engaged in preparative organic chemical work must use the laboratory notebooks
supplied by the Main Stores. These notebooks are printed on every left-hand page with a blank
assessment grid (see Examples 1 and 2, pp. 7–8). Fill in the upper part of the grid with the
names, quantities, and hazards of all of the chemicals to be employed in that experiment. The
hazards information is most conveniently obtained from the COSHH computer database
(http://www.nottingham.ac.uk/chemistry_internal/safety/coshh/index.php). Or consult the
Aldrich chemicals catalogue. For most chemicals you will find the EEC risk phrase, signified
for example by R 36/37/38. These numbers can be interpreted by referring to the page
‘Hazardous Products’ near the front of the Aldrich catalogue.
6
●
The database also automatically selects the appropriate handling protocols (i.e. fumehood,
rubber gloves, etc.) for each chemical. Hence, the protocol to be adopted for the experiment is
the most stringent among all those listed for the chemicals in question. The working protocol
is selected in the COSHH assessment grid by checking the appropriate boxes.
●
If the hazards for one (or more) of the reagents is unknown (i.e. something new that you have
just synthesised) then the minimum protocol is GCLP + fumehood + rubber gloves. (GCLP
= good chemical laboratory practice – see p. 19).
●
In the Working Practice part of the COSHH grid there are various other boxes that may need to
be checked. For example, if one of the chemicals is butyllithium you must first have read the
specific Safety Protocol on Pyrophorics (available on the departmental web page). Work with
these is covered by a standard protocol, so you would need to check the “Inert Atmosphere”
and “Pyrophorics” boxes.
●
Next check the appropriate box for the Primary Containment of the reactants; if one of these
descriptions does not fit your requirements, then give a brief description alongside one of the
unattributed boxes, and check that box. Think – is the primary containment sufficient for the
reaction in hand?
●
The “Other Risks and Control Measures” and “Emergency Procedures” part of the grid are
there to make you think about what other risks may arise from the experiment. Is the product
or a by-product of the reaction hazardous? How can these risks be minimised? What should
be done if the experiment goes wrong and the reaction mixture is released uncontrollably into
the laboratory? You must plan ahead for such contingencies. To help you in making such
decisions, two examples of COSHH Assessment grids are given on pages 7 and 8.
●
The experiment must also be placed into one of four categories A–D, depending on the
potential risk which dictates the level of supervision that is required (see p. 4).
●
Repeated experiments do not require a full assessment (simply cross-reference to the previous
assessment) provided that the previous assessment is within 5 pages in the same book and
that no significant changes in reaction scale or method are being made. At the top corner of
the right-hand page is a printed rectangular box for inserting your personal unique number for
the experiment. This number should also be used for labelling spectra and other data generated
by the experiment.
7
Example 1. Friedel-Crafts reaction of iso-butylbenzene (50 ml) with acetyl chloride (20 g) using
aluminium trichloride (37 g), 0°C  20°C.
Chemicals
Quant.
iso-Butyl benzene
50 ml Eye irritant, flammable
Acetyl chloride
20 g
Aluminium trichloride
37 g
Working
Practice
(GCLP
PLUS:–)







Fume hood
Rubber gloves
PVC gloves
Heavy gloves
Screens
Full face shield
Dust mask
Primary Containment:
 Inert atmosphere
 Spillage tray
Standard Protocols:
 Pyrophorics
 Hydrogenation
 Peroxides
 Open Flask
 Flask + condenser

Risk Category:
Irritating to eyes,
respiratory
system and skin, highly
flammable
Irritating to eyes,
respiratory
system and skin, harmful,
reacts
violently with water







UV light
Diazomethane
Liquid ammonia
Ozone
HF
 Multineck flask &c.
 Sealed flask / tube

Scrubber for HCl evolved; final distillation at reduced
pressure using an oil bath.
Flush all spillages to drain with copious water.
Other risks and
Control Measures:
Emergency
Procedures:
Hazards
 A
 B
 C
 D
Signature:
8
Example 2. Methylation of methyl orsellinate (12.64 g) using methyl iodide (197 g), dry acetone
(150 ml), and potassium carbonate (80 g); magnetic stirring and reflux for 12 h.
Chemicals
Quant.
Hazards
Iodomethane*
Methyl orsellinate
197 g
12.64
g
150 ml
80 g
Carcinogen, toxic, irritant
Hazards not known
Acetone
Potassium carbonate
Working
Practice
(GCLP
PLUS:–)







Fume hood
Rubber gloves
PVC gloves
Heavy gloves
Screens
Full face shield
Dust mask
Primary Containment:
 Inert atmosphere
 Spillage tray
Standard Protocols:
 Pyrophorics
 Hydrogenation
 Peroxides
 Open Flask
 Flask + condenser

Highly flammable#
Harmful by inhalation,
skin contact
or ingestion







UV light
Diazomethane
Liquid ammonia
Ozone
HF
 Multineck flask &c.
 Sealed flask / tube

None. All work-up procedures carried out in the fume
hood; crude product carried through to the next stage.
Evacuate laboratory; re-entry only by personnel wearing
breathing apparatus and rubber gloves. Open lab. windows.
Mop up spillage if possible and place swabs in a sealed jar –
otherwise flush to drain with copious water.
Other risks and
Control Measures:
Emergency
Procedures:
Risk Category:
 A
 B
 C
 D
Signature:
*
Here it is assumed that the student is inexperienced in the use of alkylating agents (hence risk
Category A). A person experienced in the use of alkylating agents would enter Category B. In
this case, the experiment must only be conducted under direct supervision.
#
Flammability must be considered when deciding on apparatus design, method for heating (if
applicable), and risks posed by nearby experiments.
9
6. The COSHH Database
●
The COSHH Database can be accessed from the School of Chemistry’s website
(http://www.nottingham.ac.uk/chemistry_internal/safety/coshh/index.php)
●
The Database can be searched by chemical or owner to find out who has a stock of any of
>12500 chemicals. For each chemical there is a complete hazard listing and details of good
working practice and disposal procedures .

Chemicals can be added by clicking on ‘Submit New Chemical’ and following the instructions.
Please note that even if a chemical already exists on the database you must add your research
group (by entering your supervisor’s name) as a new owner.
●
It is vital that the Database be kept up-to-date and be free from error. Any discrepancies,
errors or points of disagreement should be given in writing to Dr. Bertram
([email protected]). If you are in doubt, or have cause to suspect that the
hazards entered for a given compound may be incorrect, then consult the Aldrich chemicals
catalogue. For most chemicals you will find the EEC risk phrase, signified for example by R
36/37/38. These numbers can be interpreted by referring to the page ‘Hazardous Products’
near the front of the Aldrich catalogue.
●
Keeping the data up-to-date is a simple routine. Proceed as follows:(a) If a chemical on your group's or laboratory's listing is used up but immediately re-ordered,
then no action is necessary – unless the stock-holding has changed. # .
(b) If a chemical is used up and not re-ordered, it should be deleted from your listing. The
chemical name itself will not deleted from the database main file.
(c) If a chemical not on your group/laboratory listing is ordered or taken from the stores,# then
you must immediately add that chemical name to your listing. If you cannot find the
chemical, first try the common synonyms – the database largely follows the naming
protocols used in the Aldrich catalogue.
(d) Your group or laboratory should up-date its chemical inventory regularly – say once every
quarter.
#
Note: All commercial chemicals on receipt must be coded on the label (use heavy pencil in
preference to a permanent felt tip marker) with your supervisor's initials, and the month and year
of purchase (e.g. GP/11/08). This not only helps to establish ownership, but also gives an
immediate indication of the age of any chemical.
10
D. EMERGENCY PROCEDURES
1. The Emergency Alarm
(a) General
●
The emergency alarm is a continuous-sounding siren. It is tested just before 09.00 every
Monday. Alarm points are located generally near to a corner of the building, near the
intersection of corridors and near the main staircase. The alarm can be activated by breaking
the protective glass cover to the bell-push. If the fire alarm has to be sounded, the emergency
call must be backed-up by a telephone message (Tel: 8888 - internal).
●
All users of the building must familiarise themselves with the various exit routes from their
working areas. All exit points are clearly marked, and must be kept clear of obstructions at all
times. All fire doors must be kept closed and not wedged open.
●
Be sure that you know the location of the nearest telephone, fire alarm, extinguishers, fire
bucket, fire blanket and safety station for other equipment.
(b) Emergencies and Evacuation
If you discover an emergency situation, raise the alarm immediately. Do not try to contain the
emergency situation unless it is within your competence to do so and you do not put your life at
risk. Adopt a calm attitude and, unless you are a member of staff, evacuate the building by the
nearest fire exit.
ON HEARING THE FIRE BELL
●
If practical, make all apparatus safe (e.g. turn off all heating sources).
●
Close windows and doors on leaving, but leave the lights on.
●
If you are the last person to leave a room or laboratory, alter the slide indicator on the door
so that the GREEN sector is visible. (i.e. GREEN = room has been checked and
completely evacuated).* Demonstrators must ensure that undergraduates in their class
have left before they themselves evacuate the teaching laboratories.
●
Evacuate the building. DO NOT USE THE LIFT. Assemble in the the paved area in
front of the GG library (i.e. adjacent to Pope, GG library, and the lawn in front of
Maths/Physics). Keep at least 20 metres away from the Chemistry building itself!
●
Remain at the assembly point while routine checks are made;* do not re-enter the building
unless told it is safe to do so by the Assembly Point Officer. The Assembly Point Officer
11
and the Safety Officers for the three sections of the Department will normally be wearing
fluorescent yellow jackets for ease of identification.
IF AN EVACUATION IS NECESSARY OUT OF NORMAL WORKING HOURS, A SENIOR
PERSON PRESENT MUST TAKE THE RESPONSIBILITY OF CHECKING FOR ANY
MISSING PERSONS.
* Members of Staff have the task of checking that the evacuation has been completed. These
procedures, which are based on a fire token system, are the subject of specific instructions and
training. The door of every room in the Department is fitted with a slide indicator. Normally these
show RED. After checking during an evacuation, the indicator is changed to GREEN to give an
immediate simple indication that the room is empty of personnel. The indicators have no other
purpose; do not fiddle with them and ensure that those for the rooms you use routinely show
RED. On returning after an emergency evacuation, make sure that the indicator for the room you
use is altered back to show the RED sector.
2. Types of fire and fire-fighting
If in any doubt that the fire might get out of control, sound the fire alarm. Do not take personal
risks. If practicable, tackle the fire with the fire fighting equipment available. Make use of the
appropriate fire extinguisher (see below).
Fires are classified according to British Standard EN2 (1992). The classification gives useful
information to the emergency services. Electrical fires are not classified separately, but such
equipment should first be disconnected from the mains:
Class A Fires involving ordinary combustible materials such as wood, cloth, and paper are usually
tackled with water or CO2 extinguishers. (Caution the force of a CO2 extinguisher fired
into a confined space, such as a waste bin, may shower the firefighter with burning embers
because of the back-draught! CO2 is often not effective for large fires because of reignition).
Class B Fires involving flammable liquids such as petrol, paraffin, organic solvents, liquefiable
solids, oils, greases and fats (CO2 may be effective for small fires – unless at a height, but
re-ignition is a problem with larger fires. Foam and dry powder extinguishers efficiently
extinguish large fires, but create a mess).
Class C Fires involving gases – extinguish only after isolating the supply. Extinguishing before
may cause an explosion.
12
Class D Fires involving burning metals and some of their compounds such as NaH and LiAlH4.
(Special extinguishers are required with training for staff in handling combustible metals;
do not use CO2 or water-based extinguishers).
Fire extinguishers, fire fighting points, emergency stations and breathing apparatus sets will be
clearly identified and must be kept clear of obstructions; these facilities must not be abused. Items
of such equipment must not be removed (except for their intended use) without the express
permission of an authorised member of staff. Inform Mr J G Gamble if extinguishers or breathing
apparatus are used so that the supplies can be replenished.
3. Safety Stations
The Safety Stations (one is located in C.32 and one in C.13) should contain the following items for
emergency use:
●
●
●
●
long and short handled brushes
long handled squeegee
mop and bucket
sand bucket.
●
●
●
●
hand shovel
long handled tongs
lidded metal bucket
large polythene sheet (for flood protection)
Items must be returned immediately after use. Report the absence of items to Mr. D. Toplis.
4. Breathing Apparatus
Sets are available in the red-painted wooden cabinets located on the back stairs opposite lab. C.33.
Instruction in the use of the breathing apparatus is given every October. If you miss this, or require
a refresher, see Mr D. Toplis.
Certain people should not use the breathing apparatus in an emergency (i.e. those with heart
conditions, respiratory problems and those with beards or spectacles that prevent the face mask
from seating properly).
If there should arise an uncontrolled fire or release of a toxic substance, clear the laboratory
IMMEDIATELY and, if necessary, adjoining laboratories. Close the laboratory doors.
Re-entry into the affected area may be made ONLY IF:
●
Any fire is localised, and there is no danger of flash-over if the laboratory door is opened.
●
The means for dealing with the problem, and for effecting decontamination, have been
properly decided.
AND IF
13
●
Breathing apparatus is worn and the training protocols are strictly followed. DO NOT TAKE
RISKS. When in the affected area, improve ventilation FIRST by opening windows and
turning on the fume hood draught.
●
In addition to the breathing apparatus a laboratory coat and any other necessary protection (e.g.
rubber gloves) are worn.
●
A SECOND PERSON, similarly attired is available to act as a back-up immediately OUTSIDE
the affected area. This second person must have the person entering the area in full view so
that immediate assistance could be given if required.
●
NO RISKS ARE TAKEN.
IF IN DOUBT LEAVE MATTERS TO THE
PROFESSIONAL FIRE SERVICES.
If a fire is not involved, but re-entry is made to deal with a toxic hazard, close the laboratory door
after opening the windows and ensuring that the fume hood fans are switched on BEFORE dealing
with the problem.
DAVID CHAMBERS-ASMAN GAMBLE OR DANE TOPLIS MUST BE INFORMED IF THE
BREATHING APPARATUS IS USED SO THAT THEY MAY GET THE AIR SUPPLY
RECHARGED.
5. Basic First Aid
These notes are intended only for the initial treatment of injuries; in all cases seek medical attention
immediately – see inside back cover for emergency telephone numbers. The names of current First
Aiders are printed on the lists attached to the breathing apparatus cabinets on the rear stairs
opposite laboratory C33.
Always:
●
●
be calm; give confidence to the injured person.
ensure that there is no further danger to the casualty or yourself.
(a) Burns
●
The effects of burns and scalds are similar, and seriousness depends on area and extent rather
than the depth of injury. All burns are complicated by shock and subsequent infection.
14
●
The area of most burns and scalds, including the clothing involved, is usually sterile initially
and every effort should be made to keep it sterile.
●
HEAT BURNS: Serious heat burns should have a dry sterile dressing applied. Do not use an
adhesive wound dressing or ointment of any sort.
●
Clothing etc. sticking to burns should not be removed. Never burst blisters.
●
SMALL HEAT BURNS: Immerse in clean cold water for a minimum of 20 min. Apply a dry
sterile dressing to the area concerned.
●
CHEMICAL BURNS: Flush with cold running water for about 20 min. and apply a dry sterile
dressing.
●
COLD BURNS: These may be caused by cryogenic materials such as solid CO2 or liquid N2.
Thaw slowly in lukewarm water and then cover with a sterile dressing. Medical help must be
sought if the area frozen is extensive or deep. Do not remove adhering clothing until thawed
thoroughly.
(b) Chemical Splashes
All corrosive acids and alkalies should be washed off the skin immediately with plenty of water if
necessary. Cover any wound with a dry dressing.
●
There may be a more appropriate action in the case of specific chemical reagents (see the
appropriate wall charts). In the case of bromine, for example, wash off the skin with light
petroleum, followed by water. If in doubt, wash off only with water; some organic solvents
have the ability to carry chemicals through the skin.
●
EYES: Chemical splashes in the eye must always be washed out immediately with water. Use
an eye wash bottle filled freshly with cold tap water; if one is not immediately to hand, then
use the emergency shower at a low flow rate after flushing out the pipework. Medical help
must be sought.
(c) Cuts
The way to control blood loss is to restrict the flow to the wound and therefore encourage clotting.
This can be done by pressure or elevation.
●
Apply pressure through a suitable sterile pad with thumb and fingers to close the sides of the
wound together. Avoid contact with the casualty's blood. Raise the injured part if possible and
15
apply a sterile bandage. This should be tight enough to control bleeding but not so tight as to
cut off circulation. If stitching is required, escort the injured party to the Cripps Health Centre
or Queen's Medical Centre. If more serious, continue with the first aid until the ambulance
arrives.
(d) Minor Injuries
Suitably stocked First Aid boxes are positioned throughout the building. Stocking is controlled by
the Department; report any deficiencies to Mr. A. Spibey so that the supplies may be replenished.
For treatment refer, if necessary, to the appropriate wall chart; see also the bibliography section at
the end of this manual.
(e) Poisoning
●
Quickly ask the conscious patient what has happened in case he loses consciousness. There
may be a specific antidote. Keep any vomited material for examination, BUT DO NOT
INDUCE VOMITING. See that medical help is summoned immediately.
●
Meanwhile, if the lips show signs of burning, cool them by giving the casualty water or milk to
sip.
●
Call a doctor or an ambulance. Try to identify what the casualty has swallowed, and tell the
doctor or ambulance control officer.
●
If unconsciousness occurs, but normal breathing continues, lay the person in the recovery
position as detailed below. TO LEAVE AN UNCONSCIOUS PATIENT LYING ON HIS
BACK MAY CAUSE THEIR DEATH.
If breathing stops, resuscitation (CPR) becomes necessary – this should only be attempted if
you have received First Aider training. Resuscitation of a casualty of poisoning requires
special techniques and facilities.
(f) Unconscious Patients
●
Lay the person in the recovery position (shown below), make sure that breathing continues and that
his air passages are not blocked. Ensure that medical help (and a First Aider) has been summoned.
16
(g) Electric Shock
Even 60 volts AC may be sufficient to cause unconsciousness and death. ALWAYS SWITCH
OFF CURRENT FIRST BEFORE APPROACHING THE PATIENT. Summon medical help.
If breathing has stopped, summon the nearest First Aider to start emergency CPR.
6. Accident Reporting
The HSE have to be notified about some types of accident Ð hence ensure that all relevant details
are recorded at the time.
An Accident Report Form (available online:
http://uiwwwliv01.nottingham.ac.uk/ARI/) must be completed for all accidents involving:
●
●
●
●
●
●
●
●
Personal injury (even if only slight).**
Explosion.
Fire necessitating the use of any item of fire-fighting equipment.
Any accident necessitating the use of the breathing apparatus.
Spillage of toxic or obnoxious material necessitating the evacuation of the laboratory.
Spillage of highly toxic material, even if safely contained by the fumehood.
Failure of apparatus or equipment if it could have resulted in personal injury or damage.
Failure of services that could have resulted in a serious accident.
** Please note: By far and away the most common sources of injury arise from cuts and from the
results of chemical action on the skin. Cracked and chipped items of glassware should be given to
the glassblower for repair. Protect your hands when attaching PVC or rubber tubing to condensers,
etc. Wear rubber gloves if there is the slightest risk that chemicals might contact your skin; wear
heavy gloves, or use clamps, when handling hot apparatus.
17
E. RULES GOVERNING THE USE OF THE CHEMISTRY
BUILDING
1. Normal Working Hours
The Chemistry Department is open, and staff are usually present from 08.30 to 18.00 hours,
Monday to Friday, excluding official University holidays that indicate the buildings are shut. This
constitutes 'normal working hours'. Out of normal working hours you must sign in and out in the
book kept in the corridor between the main foyer and the workshop block.
When the building is locked, entry and exit is available to official card-key holders only. Cardkeys are to new researchers when they start, and may not be lent out. Anyone admitted by a cardkey holder is deemed to be entirely the responsibility of the card-key holder. In an emergency,
other exit doors can be opened with the main door key. If accidently locked-in by the Security
Staff, telephone the Security Control Office (Internal Tel. No. 13013).
2. Outside of Normal Working Hours
Operations outside of normal working hours are subject to the following conditions:
●
Experimental work may be performed only if there is at least one other research worker within
easy calling distance. No radios etc. may be played!
●
Experimental work is restricted to operations with which the individual is familiar and which
are not especially hazardous.
●
You are responsible for ensuring that all services not required are turned off on departure.
Windows and doors must be shut, you must sign-out in the ‘Out-of-Hours’ register, then lock
the outside door on departure.
●
Any experiment left running is subject to the usual overnight card regulations (see Section E
4).
3. Building Services
Any failure or fault in the gas, water, electricity, or drainage services, or in ventilation (including
fume hood draught) should be reported to Mr. D. Chambers-Asman (C6) or Mr. D. Toplis (C2).
●
Services MUST be turned off when they are no longer required. Particular care must be
taken with connections to the water supply and drainage from apparatus – floods can be
18
exceedingly expensive and create unnecessary animosity with the other sections of the
Department.
●
It is particularly important to switch off electrical apparatus – including fume hood fans –
if no longer required. Occasionally, the electricity supply to the Department suffers
interruptions. On reconnection, the sudden surge to equipment left on can result in blown
fuses or the tripping of safety devices. Thus vital equipment and important experiments
can be jeopardised by laziness or lack of thought.
4. Overnight or Unattended Experiments.
Experiments that are left running overnight, or without close supervision, are a constant source of
potential disaster for, should anything go wrong, then immediate remedial action would obviously
not be available. Overnight or unattended experiments are allowed only if the following protocol is
strictly obeyed:
●
The water supply must be connected by flexible plastic tubing.
●
All flexible tubing must be firmly clipped onto the apparatus, the supply tap, and onto any
intermediate unions. The simple sleeve fitting of one flexible tube inside a flexible tube of
larger diameter is insecure, and is not allowed.
●
The experiment must be in a stable condition when it is left (e.g. boil up rate in reflux must
have been steady for the preceding half hour). Insecure joints (stoppered) must be secured
with spring clips.
●
The area immediately surrounding the equipment must be cleared of chemicals (especially
inflammable solvents) and any other equipment or debris not in use.
●
The experiment must be accompanied by a properly completed 'Overnight Card'. Write down
on
the card the information that a Security Officer (a non-chemist) would need to deal with any
mishap. Use full chemical names only.
●
Heating must be by electrical means only.
●
'High risk' experiments, including those involving > 500 ml of inflammable solvents, must be
checked by an experienced research worker (i.e. your supervisor or his nominee) who must
countersign your overnight card.
19
F. SAFETY IN THE LABORATORIES
1. Good Chemical Laboratory Practice
In all of your work in these laboratories you must adopt good chemical laboratory practice (GCLP)
to safeguard both your health and safety and that of others who may be affected by what you do, or
fail to do. Basically, this means:
a) Safety glasses must be worn at all times within the chemical laboratories. A laboratory coat,
properly fastened, must be worn at all times in the labs. Do not expose large areas of skin to
possible chemical attack (i.e. no bare arms, bare legs, open-top shoes). Tie-back long hair.
b) Complete your COSHH assessment and have it checked, before you start work on any
experiment. If you are unsure of the properties of any substance, then adopt the minimum
protocol of GCLP + fumehood + rubber gloves.
c) Overnight and unattended experiments must be accompanied by an ‘Overnight Card’. The card
must detail sufficient information so that a non-chemist can deal with any mishap safely in your
absence. Note: if you abuse this system, this concession will be withdrawn!
d) Clear-up all spillages immediately. Keep your bench, fumehood and communal areas clean and
tidy at all times. Dispose of chemical waste (by the approved method for that material) as soon
as it is obtained – not at a later date. Wash-up apparatus at least on a daily basis.
e) Only water-soluble non-toxic and non-obnoxious chemicals may be disposed of via the sinks
(e.g. acetone rinsings of reaction flasks are OK, dimethyl sulfoxide residues are not OK). Other
waste must be place in the approved bins (glass in the glass bin, silica or alumina in the silica
bin, paper towels in the general waste bins, syringe needles in the sharps container, etc.).
f) Write-up you lab. notes as the experiment progresses – not later. Keep all information,
spectra etc., generated by the experiment in good condition, and make sure that it is all crossreferenced to that experiment.
g) All chemical samples must be properly and securely labelled (felt tip on glass is not
acceptable!), and stored safely. All reagents used in the experiment must be returned to their
usual locations as soon as possible.
20
2. Additional Safety Measures
Various items for the additional protection of the body are freely available in the Department, and
must be used as demanded by the nature of the work in hand. Specifically:●
Pull down the front of a fume hood when the experiment therein is underway and requires no
further immediate attention.
●
Use the safety screens provided for all experiments that are thought to be hazardous. Reactions
conducted in Carius tubes must be further shielded by purpose-made metal screens.
●
Refuse entry into the laboratory by anyone who is not wearing eye protection.
●
When necessary wear suitable gloves; rubber or plastic to avoid chemical contamination of the
hands; heavy fabric for handling hot apparatus or sealed tubes. Never immerse gloved hands
into chemicals for rubber and plastic are permeable to many compounds. Wear double gloves
when handling Hydrogen Fluoride or its solutions (outer glove to be of PVC).
●
Wear a dust mask when handling light powdery materials, or when using a mechanical grinder.
3. Preventing Accidents
(a) Fires
Almost all organic solvents are flammable. The only common exceptions are CCl 4, CHCl3 and
Cl3C.CH3 (inhibisol). Many solvents are highly flammable since they have high vapour pressures
and low flash points. HENCE:
●
Smoking in the laboratories is strictly prohibited.
●
Check nearby experiments before lighting a Bunsen burner.
●
Apparatus design must prevent solvent vapours from contacting ignition sources (even a
hot plate or mantle).
●
Solvent stills (if allowed by the Safety Officer) must be sited in safe areas, away from
escape routes. Insecure joints must be fitted with spring clips; glass taps must not be
capable of falling out.
21
●
The doors to the solvents cabinets must be kept firmly closed. Keep fire doors closed at
all times.
●
No more that 50 litres in total of flammable solvents (including waste solvents) may be
housed in any one laboratory.
●
Solvents containers must not be left alongside operational experiments.
●
DO NOT store solvents in open containers in the refrigerator.
●
Always use anti-bumping agents or rapid stirring before boiling liquids. If you forget you
must allow the liquid to COOL FIRST, UNDISTURBED, before adding the nucleating
agent.
●
The overnight room must be used for high fire-risk experiments.
●
Finely divided hydrogenation catalysts must be wetted before disposal; noble metals
should be saved for later recovery.
●
The alkali metals, their hydrides and organometallic compounds and complex hydrides
can inflame in air or on contact with other reagents. Ensure that you receive proper
training in their use and disposal from your supervisor.
NOTE: Separate regulations apply for the use of:
●
Air Sensitive Pyrophoric Reagents.
●
Photochemical Reactions.
The appropriate specialist Safety Booklets are kept in the box of Safety Manuals in each laboratory;
they must be read before such work is started for the first time. Such experiments are classified as
Category A (direct supervision essential) until you have been trained in the necessary procedures.
(b) Explosion
An explosion can arise from a distinct detonation (even in an open vessel), or from the build-up of
excess pressure, or from an uncontrolled exothermic reaction. Severity is linked to scale, but some
compounds detonate with extreme violence even in small quantities. For example, 5g of acetyl
peroxide destroyed the hands of a chemist handling the neat material. Potential Detonators
include:
●
Organic perchlorates.
perchlorates.
●
Diacyl peroxides RCO.OO.COR (R = alkyl).
●
Most diaroyl peroxides (ArCO.OO.COPh) and polynitro-aromatics must be stored WET to
prevent their accidental detonation. Some are exceedingly dangerous – always check BEFORE
preparing them.
Be aware of your chemistry if using perchloric acid or inorganic
22
●
Some peracids (e.g. dinitroperoxybenzoic acid) are highly dangerous. CHECK BEFORE
MAKING PERACIDS. Some literature recipes for peracid syntheses are not to be trusted.
●
Peroxides can arise through the autoxidation of olefins, ethers, and alkyl aromatics, especially
if they contain an  tertiary C–H group. NEVER store these materials in bottles with ground
glass stoppers. DO NOT DISTIL TO DRYNESS. Test for peroxides before using old
reagents in this category.
●
Do not prepare diazomethane in scratched or ground-glass apparatus.
●
Use AZIDES with great care; do not allow sodium azide to contact lead metal or lead salts,
including lead sink troughs.
●
SILVER AZIDE is a very sensitive and violent explosive. It can form in solutions of
ammoniacal silver nitrate (silvering solutions) if not made up correctly. DO NOT store such
solutions – they can DETONATE SPONTANEOUSLY when moved.
Warning to others: Potentially explosive chemicals must be labelled "DANGER – POTENTIAL
EXPLOSIVE" and the BS 5378 'Caution - Risk of Explosion' sign used.
The following mixtures frequently detonate:
●
●
fluorine and organic compounds.
alkali metals and polyhalogenated compounds.
concentrated or fuming nitric acid and organic compounds.
nitrogen oxides and organic compounds
complex hydrides and alkyl ethers at about 1600C.
permanganic acid and organic compounds.
strong oxidising agent/reducing agent mixtures.
alkylating agents and inorganic perchlorates.
concentrated H2O2 solutions (or inorganic peroxides) and several classes of organic
●
compounds.
iodine and ammonia solutions (NI3 is a highly dangerous detonator).
●
●
●
●
●
●
●
NOTE: Separate regulations apply to work involving use of:
●
●
Hydrogenation equipment (both atmospheric and high pressure).
Concentrated (>30%) hydrogen peroxide solutions (see Prof. Anderson).
The appropriate specialist Safety Booklets are kept in the box of Safety Manuals in each laboratory;
they must be read BEFORE such work is started for the first time. Such experiments are classified
as Category A (direct supervision essential) until you have been trained in the necessary
procedures.
23
Some other explosion risks:
●
●
●
●
●
Sealing ampoules. Beware of gas liberated in the reaction. Take GREAT CARE not to
condense LIQUID OXYGEN when cooling an ampoule prior to sealing it.
DO NOT subject acetylenes and other endothermic compounds (e.g. EtO2C.N=N.CO2Et) to
pressure or rapid heating.
Ensure all air is removed from hydrogenation apparatus BEFORE admitting H2 gas.
Take great care AND SEEK ADVICE (also see p. 38) before destroying residues of the alkali
metals, metal hydrides and complex hydrides.
NEVER add water to concentrated mineral acids; slow inverse addition with stirring and
cooling must be employed.
(c) Implosion
Occurs when apparatus under vacuum suffers a catastrophic structural failure. The effect can be as
bad as those resulting from an explosion. Vacuum desiccators must be used with their protective
covers in place. Evacuated bulbs must be taped or fitted with purpose-made screens. Carry out
vacuum distillations routinely behind safety screens.
AN ACCIDENT REPORT FORM (see p. 17) MUST BE COMPLETED FOR ALL
EXPLOSIONS, EVEN IF THERE IS NO INJURY OR MATERIAL DAMAGE.
4. Common Causes of Personal Injury
The majority of injuries sustained in chemical laboratories are from carelessness, and the failure to
take sensible preventative measures.
All injuries must be treated immediately (See First Aid, p. 13) and an accident report for
completed (see p. 16). A listing of qualified First Aiders in the Department is posted on the
breathing apparatus cabinets located on the rear stairs opposite lab. C.33.
a) Cuts The main causes for cuts can be eliminated by taking account of the following:
●
Do not used chipped or cracked glass apparatus. Take it to the glassblowers for repair if it is
repairable.
●
Do not leave glass or metal sharps lying around. Syringe needles must be placed in the
"Sharpsafe" containers provided. When full these containers should be given to Mr. D. Toplis
for incineration. Other glass and metal sharps MUST be placed in suitably designated
receptacles (not the general purpose waste bins); when full, empty the sharps container directly
24
into the large refuse bins located in the Chemistry Department car park. Note: Syringes must
be rendered unusable before disposal.
●
You must use the carriers provided when transporting Winchesters. The Stores have
instructions not to supply Winchesters unless the customer has a Winchester carrier.
●
Always soften plastic tubing with hot air or hot water before attaching to glass tubing.
Lubricate the plastic or rubber tubing with grease or water and PROTECT YOUR HANDS
with heavy gloves or a heavy cloth while inserting the glass tubing. Avoid using excessive
force.
●
Remove plastic or rubber tubing from glass by cutting it off.
●
Wear, or use, adequate protection during experimental work.
b) Dermatitis
This arises from chemical attack of the skin, and may appear as a rash or in the form of more
serious
lesions. Some chemicals have a sensitising action. Some individuals are much more sensitive to
chemicals than others. Seek medical attention at the Cripps Health Centre if you develop
dermatitis.
KEEP CHEMICALS OFF YOUR SKIN AT ALL TIMES. DO NOT IMMERSE GLOVED
HANDS IN CHEMICALS SINCE RUBBER AND PLASTIC ARE PERMEATED BY MANY
CHEMICAL COMPOUNDS.
Accidental splashes must be washed off the skin immediately. Use cold water unless there is a
more appropriate remedy.
c)
Chemical Burns
Many chemicals have a caustic or other severe damaging effect on the skin. Hence, adequate
protection must always be worn. PVC gloves are compulsory wear for handling hydrofluoric acid
solutions (see also p. 33).
IF ANYONE IN YOUR LABORATORY SUFFERS SPLASHING WITH SUCH CHEMICALS,
ASSIST THEM IMMEDIATELY TO AN EMERGENCY SHOWER, AND DRENCH THE
AFFECTED AREA WITH WATER.
Eye injuries SHOULD NOT OCCUR (eye protection!!!). If an injury should occur use either an
emergency shower at low pressure or an eyewash bottle freshly filled with cold tap water or freshly
opened sterile eye-washing solution. Seek medical attention.
25
d) Heat Burns and Cold Burns
Adequate protection must always be worn when handling hot objects or cryogenic materials.
Suitable clamps are often good alternatives to heavy gloves for manipulating hot flasks, etc.
●
Burns arising from a fire or hot objects must be given basic First Aid (see p. 13), and then
medical attention obtained if necessary.
●
Burns caused by cryogenic materials such as solid carbon dioxide or liquid nitrogen should be
treated promptly (see First Aid, p. 13). Medical attention must be obtained if the area
frozen is extensive, or if it is deeply frozen.
e) Ingestion
NEVER inhale, taste, or swallow ANY chemical. Always use a mechanical filler on pipettes;
NEVER pipette liquids by mouth. Wash your hands regularly, and especially before taking food.
Eating, drinking and smoking in the laboratory are prohibited.
f) Electric Shock
All electrical equipment in the Department is tested for electrical safety on a regular basis. Hence,
you must not import electrical items into the Department.
●
D.I.Y. repairs of electric equipment ARE PROHIBITED. Return items for repair if bare
contacts or wires are exposed, or if the cable is frayed.
●
If the fuse blows, get the equipment checked. If an electrical trip-switch operates, first check
for likely causes (e.g. short circuit) and remedy BEFORE reconnecting the electrical supply.
●
Turn off the power supply BEFORE giving First Aid (see p. 16) to anyone suffering from
electric shock.
Medical attention must be sought for anyone injured by an electric shock.
g) Other Injuries
Other injuries may occur from time-to-time, especially those of the "domestic variety". Give basic
first aid (see p. 14) and obtain medical help if necessary (see inside back cover for emergency
telephone numbers).
5. Tidyness
Sloppy, untidy work breeds accidents – often for other, innocent people. Hence, clear up all
spillages immediately. Clear up all other debris generated by an experiment as soon as possible.
Do not allow dirty apparatus to accumulate; wash-up at least on a daily basis.
26
The remnants of old experiments must not be allowed to accumulate. Dispose of chemical waste
regularly (see p. 37). Keep work areas as tidy as practicable; paperwork should be stowed away,
and coats and bags kept in the cloakrooms provided.
DOORWAYS, PASSAGEWAYS AND OTHER ESCAPE ROUTES MUST BE KEPT
CLEAR AT ALL TIMES.
Securely label all chemical products you make. Felt tip marking on glass is not acceptable.
Make sure that all of your personal commercial chemicals are coded with your supervisor's initials,
and the month and year of purchase (e.g. RMD/11/09). Future receipts must be documented
immediately on arrival and entered onto the COSHH Database.
PLEASE NOTE: Routine audit checks are made of all laboratories, and the Safety Personnel
have the authority to close down any laboratory considered to be unsafe. Individuals can be
suspended from further experimental work.
6. Communal Facilities
a) Research Laboratories
i)
Many of the facilities and much of the equipment provided in the individual research
laboratories are for the use only of the personnel assigned to that laboratory. This includes
fume hoods, refrigerators, ovens, rotary evaporators, electrical equipment, other
instrumentation, vacuum frames, and laboratory general chemicals and solvents.
ii) These facilities, apparatus and chemicals may not be used by personnel from other laboratories
without the knowledge and permission of the academic supervisor(s) of the personnel in the
laboratory containing the apparatus or chemicals.
iii) You must adopt a responsible attitude towards the communal facilities in your own laboratory
for anti-social behaviour will not be tolerated. In particular you must clean out thoroughly any
communal piece of equipment or apparatus after you have used it – especially rotary
evaporators.
iv) Remove all of your debris from the communal work areas on completion of your experiment.
This includes chemical reagents used in, and chemical waste produced by the experiment.
v) Use sealed containers, properly labelled, for all chemicals kept in the laboratory including
items stored in the refrigerator (or cold room store).
27
vi) Keep clear those areas on your own work bench that have been assigned to communal
equipment. Arrange for the replacement or repair of any item that is damaged whilst you are
using it. KEEP ALL GANGWAYS AND EXITS CLEAR.
vii) Personnel in each laboratory are assigned to specific tasks to ensure efficient and safe working
(e.g. waste solvents, solvent stills, fumehoods, etc.). In addition, it is expected that each
laboratory shall adopt a clean-up and disposal routine by the last day of every month. A
form noting that this self-certification has been completed must be signed by the laboratory’s
safety monitor, countersigned by the member of the academic staff in charge, and given to the
Organic Safety Officer. Regular inspections will be held, and unsatisfactory laboratories will
be closed until improvements are made.
b) Instrument Laboratories and other General Facilities
A Responsible attitude towards the facilities provided in the communal intrument laboratories is
vital for ensuring their continued smooth operation. Make sure that you clear away all of your
equipment, apparatus, and debris immediately after completion of the task in hand. Report
promptly any malfunction or other problems to the technician in charge of the facility.
c)
The Hydrogenation Room
This room, which is located above C.33, is not available on an open-access basis. The room is
locked at all times, and the key for the door is available on request from the Mr. Dane Toplis. The
log book should be completed before receiving the key, and the key must be returned to Dane
Toplis after each trip to the hydrogenation room. The sign by the stairs leading to the
hydrogenation room should be used to indicate whether the room is ‘occupied’ or ‘vacant’ – i.e.
move the slide indicator to show ‘occupied’ before entering, and return it to ‘vacant’ when leaving.
Regular inspections of the room are made, and any breakage or spill will be attributed to the
person who used the room immediately before the inspection. Hence, anyone finding the
room or equipment in an unsatisfactory condition before commencing work should report the
matter to Dane Toplis. Serious transgressions (e.g. failure to clear-up spillages, to get damaged
apparatus repaired, or abuse of the key system) may result in the offender being permanently
barred from future use of the facility.
d) Refrigerators and Deep Freezers
All materials put in refrigerators and deep-freezers must be in air-tight containers and be clearly
labelled with the names of both contents and the research worker. Commercial chemicals must be
28
coded (see pp. 10 and 30) on the label. Foodstuffs must not be stored in refrigerators or deepfreezers. Problems should be reported to Mr. D. Toplis.
NOTE: Inflammable solvents in open containers pose a very real and important fire and/or
explosion risk. Because of this all chemicals refrigerators and freezers must be fitted with
external thermostat controls to obviate sparking.
Refrigerators and freezers must be defrosted regularly, and certainly before the build-up of ice
causes problems of removal of containers, shelves or drawers.
G. CHEMICALS AND SAFETY
1. General Considerations
All commercial chemicals on receipt must be coded on the label (use a permanent felt tip marker or
heavy pencil) with your supervisor's initials, and the month and year of purchase (e.g. GP/11/98).
The appropriate entry MUST also be made onto the COSHH Database. All compounds made
during the course of your work must be properly labelled with the name or formula, the date, your
name, and any hazardous properties (e.g. 'HIGHLY TOXIC'). The use of felt tip on glass for
labelling purposes is not acceptable.
Chemicals must be stored in the purpose-made cabinets, chemical storage rooms or cold
stores and not left out on bench tops, on the floor, by sinks or in fume cupboards. The
storage should be as follows:
●
●
●
●
●
Solvents are kept in the solvents cabinets.
Chemicals which must be stored below 40C are kept in a cold store.
Other chemicals which have a CORROSIVE, IRRITATING, HARMFUL or
TOXIC attribute are kept in the vented cabinets beneath the fume cupboards.
Relatively innocuous chemicals may be stored in the room storage (if provided)
Be careful not to store powerful oxidising agents or pyrophoric materials amongst
readily combustible chemicals!
Empty chemicals containers MUST be thoroughly washed-out BEFORE disposal, and the
labels and caps removed. They should be taken to the skip EACH day.
29
2. Chemical Toxicity
Levels of toxicity of known compounds can be found in the books available in C.30, the Chemistry
Library, and the Science Library. There are many indices of toxicity, but the two you may meet
most commonly are:
LD50 (Lethal Dose 50)
–
a calculated dose of a substance which is expected to cause the
death of 50% of an entire defined experimental population.
Occupational Exposure
Limit
–
refers to the maximum air concentration of a chemical to which an
individual can repeatedly be exposed 8 hours/day, 5 days/weeks.
It is to be stressed that individuals react to chemicals to different extents, with some people being
allergic to chemicals which produce no ill effects in others. Some chemicals have a sensitizing
action. If you find yourself especially sensitive to a chemical, discuss the problem with your
supervisor.
a) Highly Hazardous Chemicals
Hazards are, of course, noted with each and every chemical listed in the COSHH Database together
with recommendations for their safe handling. In several cases the ACCIDENTS button in the
Database will alert you to potentially incompatable chemicals, or to problems that have arisen
through use of specific chemicals. However, you must accept that the Database entries can never
be completely comprehensive, and you should always proceed with caution. Compounds signified
* below may not be stored in research laboratories, and may be obtained from the Main
Chemical Store only against the signature of the academic supervisor of the project. Listed
below are particular classes of compounds which generally have high toxicity:
ALKYLATING AGENTS - HIGHLY TOXIC, CARCINOGENIC
Includes:
alkyl halides, tosylates, mesylates, trifluoromethane sulphonates.
dimethyl- and diethyl sulphate (and other alkyl sulphates).
methyl fluorosulphonate*
acrylonitrile, acrolein, crotonaldehyde diazomethane (and
diazoaliphatics).
vinyl chloride and bromide
chloroform, and carbon tetrachloride.
formaldehyde, ethylene oxide, b-propiolactone, nitrogen mustards.
chloromethyl methyl ether and bis(chloromethyl) ether.
possibly
other
30
INORGANIC TOXINS AND ORGANOMETALLIC TOXINS
Includes:
cyanide salts,* hydrogen cyanide,* hydrogen sulphide,* carbon monoxide,* nickel
tetracarbonyl,* phosgene and thiophosgene.
nitrogen oxides
hydrazines and their salts (toxic and/or carcinogenic; sensitizers)
osmium tetroxide (keep a solution of asorbic acid or “Mazola” cooking oil to hand in
case of spillage).
heavy metal salts.
selenium dioxide and elemental selenium.
nickel, chromium, beryllium, cadmium and arsenic compounds.
Bear in mind that:
– certain organic compounds may decompose to release such toxins (e.g. cyanohydrins
decompose to give HCN).
– organomercury, organoselenium and organothallium compounds and other derivatives
of heavy metals can be at least as toxic as the inorganic salts of these metals, and are
frequently much more toxic.
SOLVENTS - TOXIC AND CARCINOGENIC
Includes:
chloroform
carbon tetrachloride
benzene
hexamethylphosphoramide
1,4-dioxane
Avoid these solvents if at all possible. Dichloromethane may frequently be substituted for
chloroform or carbon tetrachloride. Substituted ureas such as tetramethylurea can sometimes be a
good replacement for hexamethylphosphoramide. Toluene is often a satisfactory replacement for
benzene. If the listed solvents must be used, then the use of a fume hood is obligatory for all
operations involving that solvent.
OTHER TOXIC AND/OR CARCINOGENIC COMPOUNDS
Many compounds besides those mentioned below may pose a toxic hazard.
Includes:
isoamyl nitrite
N-nitroso compounds
most aromatic amines
polycyclic aromatics and heterocyclics
intercalating compounds
ethidium bromide
31
acetamide
fluoroacetic acid and derivatives
urethane
1,2-dialkylhydrazines
diazoalkanes, azoalkanes, azoxyalkanes
guanidines
NOTE: The Carcinogenic Substances Regulations 1967 PROHIBIT the use or importation of 2naphthylamine, benzidine, 4-aminobiphenyl and 4-nitrobiphenyl. Controls were also imposed on
the use of 1-naphthylamine, o-tolidine, dianisidine, dichlorobenzidine, auramine and magenta.
Among naturally occurring carcinogens, mention should be made of the potent tumour-promoting
properties of the phorbol esters (from croton oil) and the aflatoxins, especially aflatoxin B1 (from
aspergillus flavus).
Several chemical compounds may not be purchased, isolated from natural sources, or synthesised
without Home Office permission under the Misuse of Drugs Regulations.
POWERFULLY CORROSIVE MATERIALS – INCLUDING HF SOLUTIONS
Since these materials rapidly destroy skin tissue, you MUST wear the appropriate gloves at all
times whilst handling them. Contact with solutions of HF is particularly insidious as HF has an
anaesthetizing action on sub-cutaneous tissue. HF burns can be very deep-seated and difficult to
cure. Anyone contemplating using HF must obtain calcium gluconate HF burn cream before
commencing experimental work.
You must wear double gloves when handling HF solutions, the outer gloves being of PVC (or the
material currently recommended for HF).
b) Mercury Metal
The TLV for mercury is 0.05 mg/m3 whereas air saturated with mercury vapour at 250C contains
about 10 mg/m3. At 500C the concentration is about 10 times greater. Poisoning by mercury
vapour is slow, insidious, cumulative and often unrecognised before irreversible damage is done.
This means that poorly ventilated rooms should never contain exposed mercury surfaces, and even
with good ventilation the exposure of mercury to air must be kept to the minimum. Exposure most
often arises from spilt mercury; the liquid globules run into cracks and crevices and can remain an
unnoticed source of vapour for a long time.
Do not transfer mercury from one vessel to another EXCEPT over a tray or basin (glass, plastic,
iron or stainless steel) that will catch any spillage. Keep mercury containers closed at all times if
you can, but if a mercury surface has to be at atmospheric pressure (as in some manometers and
reservoirs), limit the diffusion of the vapour by covering with a layer of water and by use of cotton
wool plugs. Manometers should be designed with a stopcock at the vent which can be closed when
the apparatus is not in use.
32
Treat spillages as follows:●
contain the spillage to as small an area as possible
●
IDEALLY the droplets or pool of mercury should be collected using a fine capillary connected
to a filter flask and water pump. ALTERNATIVELY, scoop up as much of the mercury as you
can into a glass, plastic or iron container. THEN make up a little scoop of paper and use a
small brush or wad of tissue to help the droplets onto the paper.
surfaces affected by tiny droplets of mercury in a spillage should be decontaminated by pasting
with a slurry of slaked lime and flowers of sulpur mixed with a little water.* The slurry should
●
be allowed to dry and about 24h later it should be removed with clean water and the surfaces
again allowed to dry. Mercury is converted into its involatile sulphide.
*
This mixture is somewhat caustic. Slaked lime is Ca(OH)2, and is obtained by mixing CaO
with about 1/3 of its weight of water.
Mercury vapour in the atmosphere can be monitored. See Mr J. Gamble for this facility if you have
reason to believe that your laboratory is contaminated.
NOTE: Many mercury compounds are toxic by ingestion, inhalation, or through skin absorption.
Mercuric salts tend to be lipid soluble and can permeate rubber or plastic gloves. Handle only in
the fume hood and treat spillages as for mercury metal. Wash off the hands with water, or water
and soap for water-insoluble compounds.
c)
Obnoxious Chemicals
Most sulphur(II) and some sulphur(IV) compounds are stench chemicals, even at very low
concentrations. The same problem arises with some compounds of selenium and phosphorus.
These materials MAY ONLY be handled in an efficient fume hood. They MUST NOT be poured
down the drains. Contaminated apparatus MUST be steeped in an oxidising solution (e.g. sodium
hypochlorite). The hazards board outside the laboratory MUST be kept scrupulously up-to-date
while obnoxious compounds are in use.
3. Laboratory Hazards Boards
A listing of all chemicals in use in the laboratory’s fume cupboards must be written on the board by
the laboratory door, and the listing MUST be kept up to date. This is done in black ink. It is
particularly important to highlight the use (or disposal) of STENCH chemicals for the reason that
the source of the problem can be readily identified if complaints are received from other people
33
inside or outside the Chemistry Department. This is done in red ink only. At low levels, sulphur
compounds can be mistaken for a gas leak!
4. Gas Cylinders
Cylinders MUST NOT BE LEFT FREE-STANDING – rather they must be kept in a trolley or
stand, or chained to a wall or bench. When not in use the gas must be turned off at the main valve,
and the reduction valve bled via the needle valve. Where cylinders are issued with operating
instructions, these must not be removed.
IT CAN BE DANGEROUS TO MOVE A CYLINDER WITH THE GAUGE STILL ATTACHED,
FOR IF IT SHOULD FALL OVER THE GAUGE MAY SHEAR OFF RELEASING THE FULL
PRESSURE WITH EXPLOSIVE FORCE. GAUGES MUST BE REMOVED BEFORE
TRANSPORTING CYLINDERS. CYLINDERS MAY ONLY BE MOVED ON A TROLLEY
OR SKATE.
Cylinders which have developed stiff, locked, or leaking valves should be returned immediately to
the store with a note of the fault attached.
The use of liquid ammonia (Category A) is the subject of a separate Safety Protocol which must be
read BEFORE training in its use is given by an experienced person.
You may use the cylinder of HCl gas only after receiving instruction and training from Mr D.
Toplis. It is vital that a rigid protocol is observed with this highly corrosive gas for it is very easy
to do irrepairable damage to the reduction valve assembly.
The use of cylinders of CARBON MONOXIDE, HYDROGEN CYANIDE, HYDROGEN
SULPHIDE, PHOSGENE AND OTHER HIGHLY TOXIC COMPOUNDS REQUIRES
SPECIAL PERMISSION AND THE PROVISION OF SPECIAL FACILITIES.
supervisor.
See your
It is expected that lecture bottles of gas, and other small cylinders will be used ONLY in a fume
hood, and that:
●
the cylinder is securely but loosely clamped to an adequate stand.
●
you have received proper instruction in the use of the gas or liquid contents from your
supervisor.
In all cases where a TOXIC GAS IS BUBBLED THROUGH A REACTION MIXTURE you
MUST make adequate provision for absorbing the surplus reagent at the apparatus vent. If in
34
doubt, check with your supervisor how to do this. HYDROGEN AND CARBON MONOXIDE
may be vented ONLY IN THE OPEN AIR OUTSIDE THE DEPARTMENT. Take special care
with flammable gases.
5. Liquid Nitrogen
The main hazards arising from the use of liquefied nitrogen are:
●
Thermal shock on the rapid cooling of glassware; an implosion may result if under vacuum.
Dewar flasks often disintegrate in this fashion and should always be encased in a rigid
container, preferably of metal. Transport Dewars ONLY in the carriers provided. Always
wear safety glasses.
●
Cold burns resulting from skin contact. Cold buns can cause severe, deep-seated injury.
ALWAYS keep liquid N2 off the skin; USE HEAVY GLOVES when handling very cold
apparatus. See p. 15 for the treatment of cold burns.
●
The inadvertent condensation of oxygen, argon, or other gaseous material.
VESSELS
COOLED IN LIQUID N2 SHOULD NOT BE OPEN DIRECTLY TO THE
ATMOSPHERE FOR LONGER THAN 1 MIN OR SO FOR LIQUID O2 MAY
CONDENSE.* Apparatus that is being flushed with argon or carbon dioxide at –1960C WILL
ACCUMULATE liquid Ar or solid CO2.
●
VESSELS CONTAINING LIQUEFIED O2, Ar, or SOLIDIFIED CO2 AND THEN
SEALED WILL EXPLODE WITH GREAT VIOLENCE IF ALLOWED TO WARM
UP. TAKE GREAT CARE IN THE COOLING AND SEALING OF AMPOULES.
●
Cold traps on vacuum lines must be allowed to thaw (by removal of the liquid N2 Dewar)
immediately after the vacuum is released and the trap is reconnected to the atmosphere.
* Mixtures of liquid O2 and organic compounds are highly dangerous through explosion and
combustion. Liquid O2 will immediately inflame cotton material (e.g. a lab. coat) on contact, and
combustion will proceed with great vigour. Liquid N2 is colourless, whereas paramagnetic liquid
O2 is pale blue. Care should be taken not to allow the oxygen content of liquid N2 in Dewar
vessels to rise to dangerous levels.
35
6. Detoxification and Disposal of Chemicals
a) Waste solvents
Laboratories are equipped with two large waste solvent containers – one for Non-Chlorinated
Waste Solvent and one for Chlorinated Waste Solvent. Waste solvent must be placed in the
appropriate container. Chlorinated solvents must not be placed in the Non-Chlorinated Waste
Solvent container. The containers must be stored in the vented cabinets beneath the fume
cupboards. When these containers are near-full, make arrangements with Mr. D. Toplis for the
transfer of their contents to the larger metal storage drums in the fire-proofed laboratory (C.43);
these are used for transport by the waste chemicals contractor.
Note: Waste solvents must have been though a vaporization-condensation cycle (i.e. distillation or
rotary evaporation) before being poured into the appropriate waste solvent container, otherwise the
metal drums can corrode severely during the storage period. Mr. Toplis may refuse to accept a
batch of waste solvent if it is seen to be contaminated.
b) Reaction Residues
Modest quantities of water-miscible non-toxic waste (e.g. inorganics, acetone, lower alcohols,
reaction residues in acetone, etc.) may be flushed down a drain with plenty of water. DO NOT
dispose of DMSO in this way since it usually contains Me2S (STENCH!!!). Small quantities of
amines should be dissolved in dilute HCl before flushing down the drain.
In general, you should avoid pouring appreciable quantities of chemicals down sinks. You must
take positive steps to prevent toxic chemicals from venting into the laboratory or the fume hood,
or from contaminating the drains.
c)
General Disposal Procedures
Disposal procedures are given with each chemical listed on the COSHH Database. The book
Destruction of Hazardous Chemicals in the Laboratory by G. Lunn and E.B. Sansone (a copy is
kept in room C.30) contains a considerable amount of useful information.
i)
Heavy metal residues, etc. (e.g. Hg, Cr, Pb, Os, Sm, etc.) should be collected separately in
suitable containers of 1 litre capacity or less. When the container is full, or no more waste is
being collected, submit the material to the Departmental Waste Disposal procedure (see p. 37).
Other toxic solids which cannot be chemically detoxified (i.e. notably Se and SeO2) may be
disposed of similarly. Note: Only Macintosh-labelled containers are allowed.
Heavy metal salts present in dilute aqueous solution, clearly, should be recovered in solid form –
otherwise the Department will have to pay a high for the disposal of water! The metal ions should
be converted into an insoluble derivative (e.g. Ba2+ → BaSO4, Pb2+ → PbS, Hg2+ → HgS, or
36
[HgI4][Cuen]2 etc., etc.) which is separated and submitted to the Departmental Waste Disposal
procedure (see p. 39). Most problems in this category may be solved by consulting a textbook on
qualitative inorganic analysis; this is your or your Supervisor’s job – the Safety Officers will not
do your literature work for you.
ii) Sulphur stench compounds Sulphur(II) and sulphur(IV) compounds and their reaction
residues must be digested in sodium hypochlorite solution. When the stench has been
removed, the hypochlorite solution may be poured down the fumehood sink with plenty of
water. If, however, the stench is not removed in, say, 2 weeks arrange for disposal through
the Departmental Waste Disposal Service.
iii) Cyanide residues must be digested in sodium hypochlorite solution for > 1 week before
disposal down a fumehood drain with plenty of water.
iv) Chromatography column absorbents (e.g. silica gel and alumina) must be placed in a plastic
bag which is then placed in the special dustbins provided.
v)
Noble metals and their residues (notably Ru, Rh, Pd, Ir and Pt) should be collected separately
in suitably labelled jars for later recovery. A one-off 50 mg sample is not worth worrying
about, but regular use of, say, Pd-C should lead to saving the residues. These should be stored
under water since the dry reagents may be pyrophoric.
vi) Chemically reactive substances Many organic and inorganic compounds can be deactivated
and/or detoxified by a suitable chemical reaction. Hydrolysis may be suitable in many cases
(e.g. small quantities of acid chlorides and anhydrides, hydrolysable 'metal' chlorides such as
POCl3, AlCl3, SnCl4 etc., HMPA under acid catalysis as noted below). It is difficult to be
specific because of the great variety of compounds in use. Always check the proposed disposal
method carefully (you should know the chemical properties of the reagents you handle!) and
consult your supervisor and Lunn and Sansone’s book on the Destruction of Hazardous
Chemicals in the Laboratory.
Do not, for example, destroy residual alkali metals, alkali metal hydrides (MH), organometallics
(MR), or complex hydrides with water (explosion risk). Usually a higher alcohol should be
employed; see your supervisor first.
If such deactivation also leads to detoxification giving water-soluble material, then these residues
may be flushed down a fume cupboard drain with plenty of water. If the deactivation does not
result in detoxification [e.g SnCl4 → Sn4+(aq.)] then the toxic problem should be handled as noted
above. Deactivation, when feasible, is always preferred for the risks posed by the waste in storage,
37
transport, or final land burial is greatly reduced. Contractors may refuse to take items which are in
a dangerous state (e.g. bottle of half-used tert-BuLi).
Many other organic or inorganic compounds are very readily deactivated and/or detoxified, even
when in the vapour state. Again, if you know the chemistry, then you should be able to work-out
(or look up) how! A few typical countermeasures are:
Hazard
Br2 aq.
Countermeasure
NaHSO3
Hazard
O3
Countermeasure
aq. NaI
HCl gas
H2O
M(CO)n
Br2/H2O
If you have a disposal problem that you are unable to solve, then consult your supervisor and Lunn
and Sansone’s book on the Destruction of Hazardous Chemicals in the Laboratory.
vii) Alkylating agents, urethane, HMPA, etc. Details for the safe disposal of these materials are
given by the COSHH Database and Lunn and Sansone’s book on the Destruction of Hazardous
Chemicals in the Laboratory (C.30).
(d) Departmental Waste Disposal Service
This is for all other toxic waste materials which cannot be detoxified further for disposal down a
fume hood drain. This category may also contain commercial chemicals which have decomposed,
or are no longer required. All of this material must not be in a potentially dangerous state.
Make sure the bottles containing the material are properly labelled with the nature of the waste. If
any material is particularly toxic, the bottle should be enclosed in a sealed plastic bag. The
containers must then be securely packed in a suitable cardboard box such that the risk of breakage
during transportation is minimised. Fill in the appropriate documentation (a specimen form is
shown on the next page), get this signed and checked by your supervisor and give the form to Mr.
D. Toplis; he will make arrangements to remove your waste to store. Spare forms are available
from Mr. D. Toplis. It is permissible to mix COMPATABLE chemicals (e.g. carboxylic acids
together, or amines together) and this results in substantial cost savings (see the COSHH database
for further guidance). The label must indicate the nature of the mixture and hazards.
38
SWS
DUTY OF CARE WASTE SPECIFICATION
SPECIALISED WASTE SERVICES
Environmental Consultants • Waste Management Contractors
Waste Producer ...............................................................................
SWS Office Use Only
Department ...................................................... Sheet No. ............
Information compiled by .................................................................
Control No: .............................
Position .............................................................. Date ....................
Date Rec'd: .............................
BOX
CODE
MATERIAL
CONTAINER
No. OF
HAZARDS
SIZE
CONTAINERS
(e.g. Flamm.,
Toxic etc.)
39
H. BIBLIOGRAPHY
1.
Safety Statement, University of Nottingham, Department of Chemistry (all personnel should
have received a copy and/or have access to a copy on the School website).
2.
Safety Handbook, University of Nottingham (all personnel should have received a copy and/or
have access to a copy on the University website).
3.
R.E. Lenga (ed.): The Sigma-Aldrich Library of Chemical Safety Data (1986).
4.
N. Irving Sax: Dangerous Properties of Industrial Materials, 6th Edn. Van Nostrand-Reinhold
(1984).
5.
a
b
c
d
Hazard Data Sheets, BDH (1989) and May & Baker (1989).
Bretherick’s Handbook of Reactive Chemical Hazards (4th Edition).
Benzene: Uses, Toxic Effects and Substitutes; Occup. Safety & Health Series.
Occupational Exposure Limits; (1991) H.S.E.
e Control of Carcinogenic Substances; (1989) H.S.C.
f Destruction of Hazardous Chemicals in the Laboratory, G. Lunn and E.B. Sansone.
6.
a
b
c
d
e
7.
W. Braker and A.L. Mossman: Effects of Exposure to Toxic Gases. First Aid and
Medical Treatment, Matheson Gas Products (1970).
H. Proctor and P.S. London: Principles of First Aid for the Injured, 3rd Edn.,
Butterworths (1977).
Protection Against Ultraviolet Radiation in the Workplace, National Radiological
Protection Board (1978).
Safety in Laboratories, Ciba-Geigy (1984).
Safety in Universities. Notes of Guidance, The Committee of V.C.'s and P.'s.
Safety publications in the Science Library: See listing in ref. 2.
40
I. EMERGENCY TELEPHONE NUMBERS
75
Cripps Health Centre
8888*
Emergency Service for Fire and Ambulance
13013
Trent Building Security (24 h cover) – use after 5pm when Emergency Service is
needed.
* Inform the person who answers the call what service is required, state the location in the
Chemistry Building. Give your name and remain available to direct the emergency service
responding to the zone concerned. Ensure that someone is stationed outside the Department, in the
car park with a view of the service road, to direct the emergency service into the building.
OTHER TELEPHONE NUMBERS FOR USE IN AN EMERGENCY
LABORATORY SUPERVISOR: See notice on lab door for name and telephone details.
ORGANIC
Prof. B. Lygo
Internal: 13541
LABORATORY MANAGER:
Mr. D. Toplis (C2)
Internal: 13539
Home: 9198419
DEPARTMENTAL TECHNICAL
MANAGER (Plumbing, Electrical
And building faults)
Mr. D. Chambers-Asman (C6)
Internal: 13517
SAFETY OFFICER:
UNIVERSITY SECURITY:
UNIVERSITY
SAFETY OFFICE
Internal: 13013
Dr. H.J. Sutherland
Internal: 13401
Organic Safety Manual 12th Edition, created 22.09.2014 by Simon Woodward
Attended introductory safety talk
or
Watched video recording
□
□
ORGANIC CHEMISTRY RESEARCH
GENERAL SAFETY MANUAL
I have read and understood the General Safety Manual. I agree to abide by the general
protocol, recommendations and prohibitions outlined therein. I further understand that
additional protocols and prohibitions may exist for work in specialised areas not covered in
this manual, and agree that before work is commenced in these areas it will be thoroughly
discussed with my supervisor and the relevant safety manual will be read.
NAME (print)............................................... Laboratory..................
SIGNATURE.............................................. Date..........................
SUPERVISOR (print)................................................
SIGNATURE............................................. Date..........................
This form must be duly completed (including the box in the top right) and signed by both
student and supervisor, and then given to the Section Safety Officer (Prof. Simon Woodward)
BEFORE work is commenced for the first time.