Poisonous
The
poison symbol is self-explanatory. Whereas most chemicals are fairly
dangerous if ingested or inhaled, many of these are dangerous even on
contact.
Environmental hazard
Relatively
rare with laboratory chemicals (most of which pose some environmental
hazard if not got rid of correctly), these require particular care to be taken on disposal.
Corrosive
Will
destroy or irreversibly damage another substance with which it comes in
contact. The main hazards include damage to eyes, skin and tissue under
the skin, but inhalation or ingestion are also very risky. Avoid contact, and bear in mind that these can (under some ciurcumstances) rust chemical cupboards.
Explosive
Again,
fairly self-explanatory, though fairly seldom seen in the average lab.
Bear in mind that noise and movement can also trigger explosion (not
just sparks/flames!).
Flammable or extremely flammable
Chemicals
to be stored in flame-resistant cupboards. Volatile solvents can be a
particular problem as they are prone to spread around from unsealed
containers. This also covers pyrophoric materials (that catch fire
spontaneously on exposure to air).
Irritant or HarmfulThis
symbol covers a wide range of (sometimes relatively minor) hazards -
with precautions such as avoid contact with the skin, do not breathe,
etc. - best to refer to relevant data sheet for details.
Oxidising chemical
Oxidising
chemicals are materials that spontaneously evolve oxygen at room
temperature or with slight heating, or that promote combustion. To be
kept away from flammable chemicals at all costs!
Whereas
the square symbols above (which tend to be the most familiar ones) will
be found on bottles & jars, diamond shaped symbols are used in
transport (mainly as they can be slotted into holders on the backs of
trucks & tankers to identify what the mess is (and how dangerous it
is) in the event of a leak.
Poisonous Gas
Used for transport of a poisonous gas - on gas cylinders, or sometimes as an indicator on vehicles.
Miscellaneous danger
Catch-all symbol for all other dangers (usually specified in the space).
Poison
More general symbol for the transport of poisonous materials (not necessarily a gas).
Flammable Solid
Flammable solid.
Stow away from foodstuffs
Harmful material to be kept away from edible material.
Dangerous when wet
This generally means that it will react fairly violently with water...
Flammable Gas
Safety symbol used for the transport or storage of a flammable gas.
Non flammable gas
Safety symbol used in the transport of non flammable (and hence often non hazardous, at least out in the open) gases.
Organic Peroxide
Chemical safety symbol used in the transport and storage of organic peroxides.
Corrosive
The corrosive symbol is used in the transport of corrosive materials - again, avoid contact with the skin.
Inhalation Hazard
Inhalation hazard transport/storage symbol.
Marine Pollutant
Marine pollutant - do not dispose of in sewer system.
Explosive
Used in the transport of explosive materials.
