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Department of Biochemistry
School of Molecular Sciences Safe Work Procedure
FLAMMABLE LIQUIDS
General
Flammable liquids are sorted into four sub-classes according to their
flash points. The flashpoint is the temperature at which vapour is given
from a liquid causing a flammable mixture with air to be formed. If this
mixture is at a concentration known as the explosive range, detonation
will occur if an ignition source is present.
The four sub-classes are:
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Class 3.PGII A liquid having a flash
point < 21° C
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Class 3.PGIII A liquid having a
flashpoint >21° C and < 60° C
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Class 3.CI A combustible liquid having
a flashpoint > 60° C and < 150° C
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Class 3.C2 A combustible liquid having
a flashpoint > 150° C
For flammable liquids with a flashpoint
below normal room temperature, a serious fire hazard may be present
unless appropriate precautions and controls are used.
Hazards
Class 3 – Flammable liquids. Risk of fire, explosion.
Risk Control Measures
• Read the Material Safety Data Sheet (MSDS) for the flammable
liquid before you use it.
• Reduce to the absolute minimum the quantities of flammable liquids
used in chemical operations or held in temporary storage.
• All potential sources of ignition must be kept from the working area.
• Transport flammable liquids carefully in stout glassware and in
quantities comfortably within your control. Winchesters (2.5L) should be
carried only in special enclosed plastic carriers.
• Make sure you know where the fire extinguishers (suitable for
flammable liquids) and fire blankets are and how to use them.
Engineering / Ventilation Controls
Flammable liquids (apart from ethanol) should be used in fume hoods,
and any spills on skin and clothes washed off immediately. Ensure access
to an eyewash facility in areas where toxic solvents are used.
Storage Requirements
Flammable liquids must be stored in a laboratory in approved
fire-resistant storage cabinets (AS. 1940-1993), sited as far away from
sources of ignition as possible. The doors must be closed properly.
Flammable liquids should be stored only in specially modified
refrigerators. Ordinary domestic type refrigerators should not be
located in areas where flammable liquids may be used, as ignition and
fire may occur from the normal sparking of ordinary switches and devices
in such units.
Store away from oxidizers and spontaneously combustible chemicals
First Aid / Spill Control Procedures
Any spills of flammable liquids must be cleaned up immediately and
the materials used in the clean up should be disposed of safely, refer
to the MSDS. Wash off immediately with copious amounts of cold water (at
least 10 minutes). Contaminated clothing should be removed as soon as
possible and thoroughly washed.
In case of contact with eyes, immediately flush eyes with copious
amounts of water for at least 15 minutes (eyewash). Seek medical
attention.
Poisons Information Centre (0 13 1126).
Wear protective clothing.
Small spill:
Do not attempt clean up if you feel unsure of your ability to do so or
if you perceive the risk to be greater than normal laboratory
operations. Use vermiculite or Polyzorb spill absorbent material to soak
up spill. Place in labelled waste container ready for disposal.
Large Spill:
Notify others in the area of spill. Evacuate area. Call the Moledular Sciences General Office (9479 2160), or Zisis Pouros (9479 1294) for clean up.
Barricade area with tape to prevent entry until arrival of response
personnel. Provide assistance and information to spill clean up crew.
Waste
Contact the Molecular Sciences General Office (9479 2160) for current waste disposal
instructions.
Special precautions: HANDLING DIETHYL ETHER
Diethyl Ether is a solvent in widespread laboratory use. On evaporation
any heat-sensitive peroxides present will be concentrated, and if
evaporated to dryness can lead to an explosion. Diethyl ether supplied
by BDH contains negligible levels of peroxide and anti-oxidants (such as
pyrogallol) are added to inhibit peroxide formation. However, peroxide
formation will commence when the container is opened, allowing air to
enter in proportion to the emptying of the liquid contents, and will
continue on prolonged storage of an opened bottle.
The following practices are recommended:
• Use dark bottles and avoid topping-up because light encourages
peroxide formation and topping-up leads to a build-up of peroxides in
the bottle.
• Opened bottles should be regularly tested for the presence of
peroxides (Merckoquant ether peroxide test strips). If the peroxide
level is > 50 mg/l the ether should be treated by shaking with ferrous
sulphate (for 1 litre of ether, use 20 ml of 25% w/v aq. ferrous
sulphate). The peroxide level should then be re-checked and the process
repeated until no peroxide is detected.
• The bench reagent bottle should be the original bottle in which ether
was supplied (eg. the BDH 500 ml bottle) and it should be kept closed
when not in use. When empty, the bottle should be discarded and replaced
with a new full bottle.
Supervisors should make their staff aware of the risk and safety phrases
printed on the right hand side of the label on every bottle of BDH
diethyl ether.
Applicable Standards and Regulations
Occupational Health and Safety (Hazardous Substances) Regulations
1999
Australian Standard AS 2243.10 (Safety in laboratories - Storage of
chemicals)
Australian Standard AS 2243 Safety in Laboratories Code Part 1-10 (See
Section 18)
Australian Standard AS 2982.1 Laboratory Construction 1997
Australian Standard AS 1940 - The Storage and Handling of Flammable and
Combustible Liquids.
(Provides guidelines for the amount and type of storage of these liquids
allowed in laboratories together with the design requirements for larger
storage facilities.)
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