DEPARTMENT OF CHEMISTRY
TEACHING LAB EXPERIMENT RISK ASSESSMENT FORM
This form must be completed jointly by the Lab Officer in charge and the Lecturer in charge. A
hardcopy of the completed form should be kept in a file together with the Project Risk
Assessment.
Name of Lecturer in Charge
Name of Lab Officer in Charge
Module / Expt No.
A/P Chuah Gaik Khuan
Activity being assessed:
Tan Lay San
CM3193/94
Organic Project
Surfactant Pillared Clays in Phase Transfer Catalysis: A New Route to Alkyl Azides from Alkyl Bromides &
Sodium Azide
PhCH 2Br

(Petroleum Ether)
Surfactant pillared clay
NaN3         PhCH 2N3  NaBr
(Water)
Reflux
Known or expected hazards associated with the activity:
Hazards of reagents, solvents and known reaction products.
State each substance and the approximate amounts to be used/produced.
List of activities involved in this experiment which inevitably entail risks. The following are the activities
being use:
1)
Glass Apparatus. Refer to prepared risk assessment on Use of Glassware
2)
Hotplate/Stirrer, Oil Bath. Refer to prepared risk assessment on Use of Laboratory Heating Equipment
3)
Electricity. Refer to prepared risk assessment on Use of Standard Electrical Equipment
4)
Fume Hood. Refer to prepared risk assessment on Use of Fume Hoods
5)
Disposal of Capillary Tube, Pasteur pipettes. Refer to prepared risk assessment on Use and Disposal
of "Sharps"
6)
UV Lamp. Refer to prepared risk assessment on
http://www.chemistry.nus.edu.sg/PSSO/safety/risk/UV.htm
7)
Quenching of Sodium: It must be done in a fume hood in the absence of water or solvents as they
may result in uncontrollable flame or explosion. Refer to
http://www.chemistry.nus.edu.sg/PSSO/safety/SafetyPrac.htm
8)
X-Ray Radiation. There isn’t any radiation detected outside the equipment. The radiation source is
cut off once the main door of the equipment is open.
9)
Waste disposal:
All organic waste have to be disposed of in the appropriately labelled waste
container placed in a secondary containment housed under the designated fume hood.
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Montmorillonite (Si7.8Al0.2)IV(Al3.4Mg0.6)VIO20(OH)4. K10: 1 g
Harmful by inhalation.
0.2M Tetraethylammonium Bromide: 4.2 g/100 mL
Caution! Causes respiratory tract, eye and skin irritation. May be harmful if swallowed.
Benzyl Bromide: 360 mg (2.1 mmol)
Large doses can cause CNS depression. This material is very destructive to the mucous membranes and
upper respiratory tract. Exposure may result in mild irritation or severe tissue destruction depending on the
exposure. Inhalation of large concentrations may be fatal as a result of spasm, inflammation, and edema of
the larynx and bronchi, chemical pneumonitis or pulmonary edema.
n-Hexane: ~5 mL for TLC
Extremely flammable liquid and vapour. Vapour may cause flash fire. Aspiration hazard if swallowed- can
enter lungs and cause damage. Harmful if inhaled or swallowed. Causes respiratory tract, eye and skin
irritation. Causes damage to the following organs: Peripheral nervous system, respiratory tract, skin, central
nervous system, eye, lens or cornea.
Diethyl Ether: 3 x 30 mL
Danger! Extremely flammable liquid and vapor. Vapor may cause flash fire. May form explosive peroxides.
Harmful if inhaled or swallowed. Causes respiratory tract, eye and skin irritation. Contains material which
causes damage to the following organs: mucous membranes, respiratory tract, skin, eyes, central nervous
system, eye, lens or cornea.
Petroleum Spirit (60-80oC): 3 mL
Danger! Extremely flammable liquid and vapor. Vapor may cause flash fire. May be fatal if swallowed.
Harmful if inhaled. Causes respiratory tract, eye and skin irritation.
Sodium Sulphate, Anhydrous: 1 g
May be hazardous in case of eye contact (irritant). May be hazardous in case of skin contact (irritant). Skin
inflammation is characterized by itching, scaling, reddening, or, occasionally, blistering. May be hazardous
in case of inhalation (lung irritant). May be hazardous in case of ingestion.
Sodium Azide: 180 mg (2.76 mmol)
May be hazardous in case of eye contact (irritant). Extremely hazardous in case of skin contact (permeator).
May be fatal if absorbed. May be hazardous in case of skin contact (irritant). Skin inflammation is
characterized by itching, scaling, reddening, or, occasionally, blistering. Hazardous in case of inhalation.
May be hazardous in case of inhalation (lung irritant). Extremely hazardous
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*amount stated are computed for the whole experiment.
Incompatible materials (special precautions):
Montmorillonite K 10, Tetraethylammonium Bromide
Materials to Avoid: Strong oxidizing agents.
Benzyl Bromide
Incompatibilities: Bases, amines, oxidizers, alcohols
n-Hexane, Diethyl Ether & Petroleum Spirit (60-80oC)
Reactive with oxidizing agents.
Sodium Sulphate, Anhydrous
Incompatibilities: Reactive with oxidizing agents, metals. Also incompatible with aluminum, potassium,
mercury, lead, calcium, silver, barium, ammonium ions, and strontium.
Sodium Azide
Incompatibilities: Highly reactive with acids. Reactive with oxidizing agents.
The risk of injury and its severity likely to arise from these hazards:
Montmorillonite K 10
Skin Contact: May cause skin irritation.
Eye Contact: May cause eye irritation.
Inhalation: Harmful if inhaled. Material may be irritating to mucous membranes and upper respiratory tract.
Tetraethylammonium Bromide
Eye: Hazardous in case of eye contact (irritant). Inflammation of the eye is characterized by redness,
watering, and itching.
Skin: Hazardous in case of skin contact (irritant). Skin inflammation is characterized by itching, scaling,
reddening, or, occasionally, blistering.
Inhalation: Hazardous in case of inhalation (lung irritant).
Ingestion: May be hazardous in case of ingestion. Ingestion may cause gastrointestinal irritation and
diarrhea.
Benzyl Bromide
Skin Contact: Corrosive
Skin Absorption: No information available
Eye Contact: Corrosive
Inhalation: Harmful
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Ingestion: Harmful
n-Hexane, Petroleum Spirit (60-80oC)
Eye Contact: Hazardous in case of eye contact (irritant). Inflammation of the eye is characterized by
redness, watering, and itching.
Skin Contact: Hazardous in case of skin contact (irritant). Skin inflammation is characterized by itching,
scaling, reddening, or, occasionally, blistering
Inhalation: Hazardous in case of inhalation (lung irritant). Danger of serious damage to health by prolonged
exposure through inhalation. Possible risk of impaired fertility.
Ingestion: Hazardous in case of ingestion. Aspiration hazard if swallowed- can enter lungs and cause
damage.
Diethyl Ether
Eye: Hazardous in case of eye contact (irritant). Inflammation of the eye is characterized by redness,
watering, and itching.
Skin: Hazardous in case of skin contact (irritant). Skin inflammation is characterized by itching, scaling,
reddening, or, occasionally, blistering.
Inhalation: Hazardous in case of inhalation (lung irritant).
Ingestion: Hazardous in case of ingestion.
Sodium Sulphate, Anhydrous
Eye: May be hazardous in case of eye contact (irritant).
Skin: May be hazardous in case of skin contact (irritant). Skin inflammation is characterized by itching,
scaling, reddening, or, occasionally, blistering.
Inhalation: May be hazardous in case of inhalation (lung irritant).
Ingestion: May be hazardous in case of ingestion.
Sodium Azide
Eye: May be hazardous in case of eye contact (irritant).
Skin: Extremely hazardous in case of skin contact (permeator). May be fatal if absorbed. May be hazardous
in case of skin contact (irritant). Skin inflammation is characterized by itching, scaling, reddening, or,
occasionally, blistering.
Inhalation: Hazardous in case of inhalation. May be hazardous in case of inhalation (lung irritant).
Ingestion: Extremely hazardous in case of ingestion. May be fatal if swallowed.
Who is at risk?
Persons handling the chemicals and as well as those present in the vicinity.
Measure to be taken to reduce the level of risk:
Proper laboratory attire and safety measures must always be used in order to reduce the level of risk. Wash
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hands thoroughly after handling. Do not take internally. Eye wash and safety equipment should be readily
available.
Eye protection: Chemical safety goggles.
Hand protection: Gloves.
Refer to PSSO SAFETY Information Center website:
http://www.chemistry.nus.edu.sg/PSSO/index.htm#undergrad
Training prerequisites:
This assessment should be read by everyone who will be using the above mentioned chemicals.
Refer to Completed Risk Assessment forms for common activities:
http://www.chemistry.nus.edu.sg/PSSO/safety/risk/risk.htm#Common
Level of risk remaining:
The level of risk is low although constant vigilance is necessary to avoid injury.
For X-Ray radiation, the level of risk is none (can not be detected by X-Ray radiation detector).
Emergency action if :
Spill:
Montmorillonite K 10
Sweep up, place in a bag and hold for waste disposal. Avoid raising dust. Ventilate area and wash spill site
after material pickup is complete.
Tetraethylammonium Bromide
Small Spill & Leak: Use appropriate tools to put the spilled solid in a convenient waste disposal container.
Large Spill & Leak: Use a shovel to put the material into a convenient waste disposal container.
Benzyl Bromide
Leak or Spill Clean-up: Before dealing with spillages take necessary protective measures, inform others to
keep at a safe distance and, for flammable materials, shut off all possible sources of ignition. Absorb on
inert absorbent, transfer to container and arrange removal by Disposal Company. Wash site of spillage
thoroughly with water and detergent. Ventilate area to dispel vapours.
n-Hexane & Diethyl Ether
Small Spill & Leak: Dilute with water and mop up, or absorb with an inert dry material and place in an
appropriate waste disposal container.
Large Spill & Leak: Keep away from heat. Keep away from sources of ignition. Stop leak if without risk.
Absorb with DRY sand or other non-combustible material. Do not touch spilled material. Prevent entry into
sink.
Petroleum Spirit (60-80oC)
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Small Spill & Leak: Absorb with an inert material and put the spilled material in an appropriate waste
disposal.
Large Spill & Leak: Keep away from heat. Keep away from sources of ignition. Stop leak if without risk.
Absorb with DRY earth, sand or other non-combustible material. Do not touch spilled material. Prevent entry
into sink. Call for assistance on disposal.
Sodium Sulphate, Anhydrous
Small Spill & Leak: Use appropriate tools to put the spilled solid in a convenient waste disposal container.
Large Spill & Leak: Use a shovel to put the material into a convenient waste disposal container. Finish
cleaning by spreading water on the contaminated surface and allow evacuating through the sanitary
system.
Sodium Azide
Small Spill & Leak: Use appropriate tools to put the spilled solid in a convenient waste disposal container.
Large Spill & Leak: Stop leak if without risk. Do not touch spilled material. Prevent entry into sink. Call for
assistance on disposal.
Fire:
Montmorillonite K 10, Tetraethylammonium Bromide, Sodium Sulphate (Anhydrous) & Sodium Azide
Noncombustible.
Benzyl Bromide
Combustible
Extinguishing Media: Dry powder, carbon dioxide or vaporizing liquids
n-Hexane
Small Fire: Use DRY chemical powder.
Large Fire: Use alcohol foam, water spray or fog. Cool containing vessels with water jet in order to prevent
pressure build-up, autoignition or explosion.
Diethyl Ether & Petroleum Spirit (60-80oC)
Product will burn. Flammable liquid, soluble or dispersed in water. Vapor may travel considerable distance
to source of ignition and flash back.
Small Fire: Use DRY chemical powder.
Large Fire: Use alcohol foam, water spray or fog. Cool containing vessels with water jet in order to prevent
pressure build-up, autoignition or explosion.
Sodium Sulphate, Anhydrous
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Fire Extinguishing Procedures: Use water spray to cool fire exposed containers or structures. Use water
spray to disperse vapours.
Sodium Azide
Small Fire: Use DRY chemical powder.
Large Fire: Use water spray, fog or foam. Do not use water jet.
Is the experiment suitable for out-of-hours operation?
Yes
No
References if any:

Montmorillonite K 10:
https://ecat.fishersci.ca/(S(tivx4hanuumuj2b1obhwblmv))/ViewMSDS.aspx?cat=AC276030010

Tetraethylammonium Bromide: http://www.sciencelab.com/msds.php?msdsId=9927621

Benzyl bromide: http://www.sciencelab.com/msds.php?msdsId=9923072

n- Hexane: http://www.cpchem.com/msds/100000000434_SDS_KR_EN.PDF

Diethyl ether: http://www.sciencelab.com/msds.php?msdsId=9927164

Petroleum spirit 60−80oC:
http://www.setonresourcecenter.com/msdshazcom/htdocs//MSDS/E/EMD/Docs/wcd00017/wcd017f7
.pdf

Sodium Sulphate, Anhydrous: http://www.sciencelab.com/msds.php?msdsId=9927278

Sodium azide: http://www.sciencelab.com/msds.php?msdsId=9927588

Facts about sodium azide : http://www.bt.cdc.gov/agent/sodiumazide/basics/facts.asp
Signature of Lab Officer in Charge:………………………………………………………………..
Date:…………………………
Signature of Lecture in Charge:………… ……………………………………..
Date:… ……………………..
Prepared Risks Assessments for standard equipment and operation are with the kind permission of Dr. Ken MacNeil, School of
Chemistry, University of Bristol.
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Activity being assessed:
Note any activity to be used which entail risk (e.g. use of glass vacuum apparatus, high pressures, high
voltage, radiation, high temperatures). Give reference to any special protocols to be followed, and if
appropriate attach copies to the risk assessment form. State any additional precautions taken to minimise
risk.
Known or expected hazards associated with the activity:
FOR EACH CHEMICAL, read the MSDS and note:a) Particular hazards (e.g. highly toxic, carcinogenic, corrosive, flammable, pyrophoric, explosive, volatile,
dust hazard). Note any dangerous combinations of properties (e.g. volatile and toxic).
b) Requirements for safe handling (e.g. fume cupboard, inert atmosphere, low temperature).
c) How to dispose of residuals

Dispose to drain, with water dilution

Neutralise, then to drain with suitable dilution

To flammable liquid waste receptacle

To non-flammable liquid waste receptacle

Keep for recovery/recycling

Keep for special disposal later (e.g. heavy metals)

Double bag and dispose to dry waste

Special procedure (specify)
Incompatible materials (special precautions)
Note any dangerously incompatible materials and hazards arising from contact of any reagents and
substances used with common materials such as paper, benches, hoses, etc.
Measures to be taken to reduce the level of risk
Include hazards of previously unknown products.
Location of work – laboratory, open bench, fume cupboard
Level of risk remaining:
Likelihood and consequences of any accident or unforeseen events whilst carrying out the activity. When
this has been done, choose the appropriate procedure:a) Close supervision and/or attendance of trained first-aider needed.
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b) Specific approval of supervisor needed.
c) Training is needed prior-to or during the operations specified.
d) Training is complete and only general laboratory competence required.
e) No risk perceived.
Emergency action:
a) Any special requirements to deal with accidental spillage or leakage.
b) What to do in the event of accidental exposure (skin contact, inhalation, etc.).
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