Faculty of Science

Department of Chemistry

Chemicals are classified according to their hazards and are labelled with hazard symbols and plain-text warnings, with the inclusion of risk and safety (R and S) information.

Hazard Symbols

Explosive, E
(Chemicals that explode)
• Unstable explosives
• Self-reactive substances and mixtures
• Organic peroxides
Oxidising, O
(Chemicals that react exothermally with other chemicals)
Flammable, F
(Chemicals that have an extremely low flash point and boiling point, and gases that catch fire in contact with air OR chemicals that may catch fire in contact with air, only need brief contact with an ignition source, have a very low flash point or evolve highly flammable gases in contact with water.)
• Flammable gases, aerosols, liquids, solids
• Self-reactive substances and mixtures
• Pyrophoric liquids and solids
• Self-heating substances and mixtures
• Substances and mixtures, which in contact with water, emit flammable gases
• Organic peroxides
Acute toxicity
(Chemicals that at very low levels cause damage to health OR Chemicals that at low levels cause damage to health)
(Chemicals that may cause damage to health)
• Respiratory sensitization
• Germ cell mutagenicity
• Carcinogenicity
• Reproductive toxicity
• Specific target organ toxicity following single exposure
• Specific target organ toxicity following repeated exposure
• Aspiration hazard
Corrosive , C
(Chemicals that may destroy living tissue on contact)
(Chemicals that may cause inflammation to the skin or other mucous membranes)
• Acute toxicity (oral, dermal, inhalation)
• Skin irritation
• Eye irritation
• Skin sensitization
• Specific target organ toxicity following single exposure
• Respiratory tract irritation
• Narcotic effects
Compressed gases
Liquefied gases
Refrigerated liquefied gases
Dissolved gases
Dangerous for the Environment
(Chemicals that may present an immediate or delayed danger to one or more components of the environment)


Risk and Safety Phrases

Information on hazards of chemicals
R1        Explosive when dry
R2        Risk of explosion by shock, friction, fire or other sources of ignition.
R10      Flammable
R11      Highly flammable
R12      Extremely flammable
R14      Reacts violently with water
R15      Contact with water liberates extremely flammable gases
R16      Explosive when mixed with oxidizing substances
R26      Very toxic by inhalation
R27      Very toxic in contact with skin
R30      Can become highly flammable in use
R31      Contact with acids liberates toxic gases
R32      Contact with acids liberates very toxic gases

Safety phrases (S)

Information on storage, usage and other precautionary measures.

S1        Keep locked up
S2        Keep out of reach of children
S3        Keep in a cool place
S6.1     Keep under nitrogen
S7        Keep container tightly closed
S8        Keep container dry
S9        Keep container in a well-ventilated place.
S37      Wear suitable gloves
S62      If swallowed, do not induce vomiting, seek medical advice immediately and show this container or label.


Labarotary Chemical Storage

Chemicals must be stored according to their storage class. Each chemical is allocated one storage class only; those with more than one hazard characteristic are allocated according to the ranking of their hazard characteristics. This ensures that in the case of chemicals with similar or identical hazard characteristics, the same safety measures can be taken, especially against fire and explosion. Liquids or solid substances as well as preparations and products that do not fulfil the criteria of classes 1-8 are characterized as being of classes 10-13. No further differentiation in class is made between classes 10, 11, 12 and 13 as these are all substance-orientated.

LGK Designation

1 Explosion material
2A Compressed, liquefied, or pressure-dissolved gases
2B Pressurized gas packages (aerosol containers)
3A Flammable liquid materials (Flashpoint < 55 °C)
3B Flammable liquids
4.1A Flammable solid materials
4.1B Flammable solid materials
4.2 Spontaneously combustible materials
4.3 Materials that form flammable gases in contact with water
5.1A Oxidizing agents
5.1B Organic pesticides
6.1A Flammable toxic materials
6.1B Non-flammable toxic materials
6.2 Infectious materials
7 Radioactive materials
8A Flammable corrosive materials
8B Non-flammable corrosive materials
10 Flammable liquids if not LGK 3A or 3B
11 Flammable solids
12 Non-flammable liquids in non-flammable packages
13 Non-flammable solids in non-flammable packages


Safe Practice in Chemical Storage

  1. Store all chemicals by their hazards class and not in their alphabetical order.
  2. Do not store chemicals in direct sunlight or near heat sources such as ovens
  3. Date chemicals when first opened. If a particular chemical can become unsafe or deteriorate while in storage, an expiration date should also be included
  4. Do not use the lab bench for permanent storage of chemicals.
  5. Inspect your chemicals routinely for any signs of deterioration and for integrity of the label.
  6. Do not store chemicals above eye levels. If the container breaks, the contents can fall onto the face and upper body