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3. IDENTIFICATION, CLASSIFICATION AND LABELLING OF CHEMICALS

1. Introduction

The production and use of chemicals are fundamental factors in the economic development of all countries, whether they are industrialized or developing. In one way or another, chemicals affect directly or indirectly the lives of all humans and are essential to our feeding (fertilizers, pesticides, food additives, packing), our health (pharmaceuticals, cleaning materials), or our well being (appliances, fuels, etc).

The first and most essential step leading to safe use of chemicals is to know their identity, to their hazards to health and the environment and the means to control them. This knowledge should be available with reasonable effort and cost. Furthermore, this inherently complex knowledge must be organized in such a way that essential information on the hazards and corresponding protective measures can be identified and conveyed to the user in a form that is easy to understand.

The hazard classification and labelling process is an essential tool for establishing an effective information transfer so that the degree of the hazard the chemical represents for man and the environment can be recognized, the correct preventive actions be chosen, and safe use achieved.

The International Labour Organization (ILO) has adopted the Convention No. 170 and Recommendation No. 177 on `Safety in the use of chemicals at work' in 1990.

International, regional, and national classification and labelling systems are already established and tested in practice. 

  • The United Nations Recommendations on the Transport of Dangerous Goods is widely recognized and used among the UN member states. 
  • An example of a system that has been designed for use in several countries is the classification and labelling system of the European Communities (EC). 
  • Several functioning national systems, such as those of Canada and USA, may also be used as models for national systems. 
This guide could be used as training material or at places of work when individual labels are checked or prepared using the data on chemical substances listed in Annex 4. It may also serve as reference material, or as a manual, providing basic safety information on these substances.
This guide describes the labelling system used in the countries of the European Union (EU) as an example and the United Nations Recommendations on the Transport of Dangerous Goods is also briefly presented.

This document consists of: 

  • EU symbols and indications of danger 
  • EU standard risk phrases (R-phrases) 
  • EU standard safety phrases (S-phrases) 
  • list of dangerous substances with the classification and labelling requirements 
  • IARC list of cancer causing substances, carcinogens 
  • list of chemicals with properties potential to cause major hazard 
  • list of some substances and products which are subject to a ban or restrictions in EU countries 
  • UN list of hazard classes for transport of dangerous goods 
  • UN symbols for transport of dangerous goods 

2. Identification and Classification

The objective is to identify the hazardous properties of chemicals which may constitute a risk during normal handling or use, risks to health, property or the environment.

The user of the chemicals is also to be introduced to the hazards they present and given the basic information, in a suitable manner, such as using a properly made label.

In this document one component chemical is called a substance, a mixture composed of two or more substances is called a preparation.

The hazards of preparations can be assessed using the information on hazards of their component substances. (See example 2.)

For classification purposes the degree of hazard depends not only on the properties of a dangerous substance but also on the level of exposure. This refers to the concentration of hazardous components in the mixtures. In order to assess a preparation it is essential to know also the quantities of its hazardous minor components.

The EU classification and labelling system used here as an example can be applied to dangerous substances and preparations. However, this system should not be applied to medical or veterinary products, cosmetics, munitions or explosives, pesticides specified elsewhere, waste and foodstuffs or animal feedstuffs in the finished stage. These have their own specifications and requirements for labelling.

3. What is a hazardous chemical ?

The following properties contribute to risk to health resulting from acute, repeated or prolonged exposure: 
  • very toxic or toxic 
  • harmful 
  • corrosive 
  • irritant 
  • cancer causing 
  • hazards to reproduction 
  • can cause non-heritable birth defects 
  • sensitizing 
Fire and explosion hazards may be classified as follows 
  • explosive 
  • oxidizing 
  • extremely flammable 
  • highly flammable 
  • flammable 
The following properties present a hazard to the environment and are: 
  • toxic to living organisms 
  • persistent in the environment 
  • bioaccumulative 
Also substances and preparations that cannot be classified by using the above system may be regarded as dangerous if they have properties which are hazardous to health, to living organisms or if they can damage property.

4. How to pass on the information to users?

All chemicals, both substances and preparations, should have a clear marking to indicate their identity.

The packages and containers of dangerous substances and preparations should, in addition to marking only, to have a label with required information.

The label should draw attention to the inherent danger to persons handling or using the chemical.

Symbols and pictograms have been established for each hazard category listed above. The symbol forms an integral part of the label and gives an immediate idea of the types of hazards that the substance or the preparation may cause. (Annex 1)

To specify the type of danger pertinent standard risk phrases should also be included in the label. (Annex 2)

Advice on the precautions necessary in the handling of chemicals are given with standard safety phrases also included in the label. (Annex 3)

5. Where to find information about hazardous chemicals?

The chemical supplier, manufacturer or importer, should be able to provide detailed information and a Safety Data Sheet.

In certain countries, such as those of the EU, the manufacturer or importer has the obligation to find and give adequate information about a chemical for assessment of the health and environmental hazards of his chemical for handling and for its labelling.

Safety data sheets have been prepared on many dangerous substances and preparations by manufacturers. These should go together with the product to the occupational user. The information in these is not always validated or checked.

On pure substances International Chemical Safety Cards are available. These contain validated basic information, which may be used also for preparing safety data sheets on chemical preparations or products.

Lists of classified chemicals exist in several national legislations and regulations which provide information on local requirements in the handling of dangerous chemicals.

The information for classification, and labels, may be obtained from tests, from literature, from practical experience and from information requirements by international rules on the transport of dangerous substances and wastes.

Some sources of information are listed in the bibliography.

6. How to classify for a label?

The label is the basic tool to keep the user informed on the classification and the most important safety precautions.

This information must be given if the preparation contains at least one substance classified as dangerous to man or the environment or if the preparation is otherwise regarded as dangerous, e.g. flammable, explosive. (Annex 4)

In EU countries the label must clearly show 

  • the trade name 
  • the name and the address, including telephone number, of the manufacturer, the importer or the distributor 
  • the chemical name of the substance (in the case of a preparation, the chemical names of the hazardous components) 
  • danger symbols 
  • risk phrases (R-phrases) 
  • safety phrases (S-phrases) 
  • the quantity of the contents of the package or container 
The labels should be in the national, official language(s).

The label should show the chemical names of substances that are primarily responsible for the hazards. As a general rule a maximum of four chemical names on the label should be sufficient.

In some cases, more than four names may be necessary; for example all cancer causing substances in the preparation must be identified and the corresponding R- and S-phrases presented on the label.

If the preparation contains one or more of the substances requiring the following R-phrases, both the name of the substance and the R-phrase should be mentioned in the label: 

R39, R40, R42, R43, R42/43, R45, R46, R47, R48, R49, R60, R61, R62, R63, R64 
As a general rule a maximum of four R-phrases and four S- phrases should suffice to describe the risks and to formulate the most appropriate safety advice.

Symbols showing the most serious hazards should be chosen where more than one danger symbol has to be assigned. As a general rule a maximum of two danger symbols are used.

The explanation of the letter symbols appearing in the attached lists are given below. Each letter symbol refers to a danger symbol or pictogram in Annex 1:
Letter symbol Explanation
E explosive
This symbol with the word 'explosive' denotes a substance which may explode under the effect of a flame or if subjected to shocks or friction.
O oxidizing
The symbol with the word 'oxidizing' refers to a substance which releases a lot of heat while it reacts with other substances, particularly flammable substances.
F highly flammable
This symbol with the words 'highly flammable' denotes a substance which may become hot and finally catch fire in contact with air at ambient temperature or is a solid and may readily catch fire after brief contact with the source of ignition and which continues to burn/to be consumed by chemical reaction after removal of the source of ignition. If it is gas it may burn in air at normal pressure. If it is a liquid it would catch fire with slight warming and exposure to a flame. In contact with water or damp air the substance may release highly flammable gases in dangerous quantities.
F+ extremely flammable
The same flammable symbol as above with words 'extremely flammable' denotes e.g. a liquid which would boil at body temperature and would catch fire if vapours are exposed to a flame.
T toxic
The symbol with skull and crossed bones with the word 'toxic' denotes a highly hazardous substance.
T+ very toxic
The same symbol as above with the words 'very toxic' is used to label a substance, which, if inhaled or ingested or, if it penetrates the skin, may involve extremely serious immediate or long-term health risks and even death.
C corrosive
The symbol with the word 'corrosive' will be found on a label of a substance which may destroy living tissues on contact with them. Severe burns may result from splashes of such substance.
Xn harmful (less than T)
The symbol with word 'harmful' denotes to substances which may cause health hazards less than toxic. It could refer to other types of risks e.g. to allergic reactions.
Xi irritant (less than C)
The same symbol as above with the word 'irritant'.
When more than one danger symbol is used 
  • the obligation to apply symbol T or T+ will make symbols C, Xn and Xi optional 
  • the obligation to apply symbol C will make symbols Xn and Xi optional 
  • the obligation to apply symbol E will make symbols F and O optional 
If a preparation is classified both harmful Xn and irritant Xi, it will be labelled harmful Xn, and the irritant properties should be pointed out with appropriate R-phrases. The total amount of the substance in the preparation has an effect in choosing the danger symbols, R- and S-phrases. (Annex 8)

Generally, no account needs to be taken of substances if they are present in following amounts, unless another lower limit has been specifically given: 

  • less than 0.1% by weight for substances classified as very toxic T+, or toxic T 
  • less than 1% for substances classified as harmful Xn, corrosive C, irritant Xi, 
Information such as "non-toxic", "not harmful" should not be used in the labels.

The pictorial symbol indicating danger is drawn in black and the background colour should be orange.

The dimensions of the label:
Capacity of the package Minimum dimensions in millimeters
Not exceeding three litres 52x74
more than three litres but not exceeding 50 litres 74x105
more than 50 litres but not exceeding 500 litres 105x148
more than 500 litres 148x210
Each danger symbol must cover at least 1/10 of the surface area of the label. The minimum size of the danger symbol shall not be less than 10mm x 10mm.

Example 1. Classification of a substance
1,1,1-Trichloroethane, used as solvent

Classified as harmful Xn and dangerous to the environment N, with following R-phrases and S-phrases
R 20 Harmful by inhalation.
R 59 Dangerous for the ozone layer.
S 2 Keep out of the reach of children.
S 24/25 Avoid contact with skin and eyes.
S 59 Refer to manufacturer/supplier for information on recovery/recycling.
S 61 Avoid release to the environment. Refer to special instructions/Safety Data Sheets.
The label should carry this information. Check that the impurities do not exceed the limit of notice for impurity substances classified toxic.
Example 2. Classification of a preparation:

A preparation used for degreasing metal parts contains following dangerous components
Dangerous substance % Symbol Risk phrases Safety phrases
Petroleum distillate (flash point 43 °C) 35 T R45 S53-45
1,1,1-trichloroethane 20 Xn,N R20-59 S24/25-59-61
Xylene (flash point over 21 °C) 12 Xn R10-20/21-38 S25
Preparation T,N R45-10-20/21-59 S53-45-59-61
The R and S-phrases corresponding to the number codes are:
R 10 Flammable.
R 20 Harmful by inhalation.
R 20/21 Harmful by inhalation and in contact with skin.
R 38 Irritating to skin.
R 59 Dangerous for the ozone layer.
S 24/25 Avoid contact with skin and eyes.
S 25 Avoid contact with eyes.
S 45 In case of accident or if you feel unwell, seek medical advice immediately (show the label where possible)
S 53 Avoid exposure-obtain special instructions before use.
S 59 Refer to manufacturer/supplier for information on recovery/recycling.
S 61 Avoid release to the environment. Refer to special instructions/Safety Data Sheets.

7. How to compile a label?

The name, symbol, the risk phrases of that substance and the phrases for safety precaution when handling that substance are in Annex 4.

The key to have the symbol picture is in Annex 1.

The key to have a sentence in words is for the risk phrases in Annex 2. and for the safety phrases in Annex 3.
Substance CAS number Symbol Risk phrase Safety phrase
TOLUENE 108-88-3 F, Xn R11-20 (2-)16-25-29-33
HAZARD CATEGORIES OF SELECTED CLASSIFICATION SYSTEMS
HAZARD CATEGORIES ILO UNRTDG EC USA CANADA
PHYSICAL HAZARDS
compressed gas
flammable
explosive
oxidizing
reactive
corrosive (materials)		 -
+
+
+
+
+		 +
+
+
+
+
+		 n
+
+
+
+
n		 n
+
+
+
+
n		 +
+
+
+
+
+
HEALTH HAZARDS
toxic (acute)*
toxic (other)
irritant
corrosive (tissues)
sensitizer
carcinogen
reproductive effects**
mutagen		 +
+
+
+
+
+
+
+		 +
-
-
+
-
-
-
-		 +
+
+
+
+
+
+
+		 +
+
+
+
+
+
+
+		 +
+
+
+
+
+
+
+
SPECIAL HAZARDS
environment
radioactive
infectious
miscellaneous***		 -
-
-
-		 +
+
+
+		 +
n
n
n		 n
n
n
n		 n
n
n
n
LEGEND:
+ : defined category
n : defined under other legislation or code
- : not defined
* : includes oral, dermal and inhalation toxicity
** : includes reproductive and developmental toxicity
*** : specific to UN RTDG; included in national transport legislation
Definitions of data components in labels
COMPONENTS ILO UN RTDG EC USA CANADA
FORMAT none defined size of labels varies with transport mode. Minimum label dimensions are defined for different package capacities; contrasted danger symbols and background (black on yellow background); language must be that of the country where the product is put on market. none defined 1. Supplier label:must appear on all controlled products received at work-places; required information must be set aside from sales information; surrounded by WHMIS ; must be printed in contrasting colours; must have all texts in English and French.

2. Workplace label:must appear on all products produced in a workplace or transferred to other containers by the employer; may appear in placard form on products received in bulk.
DATA ELEMENTS 1. Trade name
2. Chemical identity
3. Supplier identification.
4. Hazard symbols
5. Risk phrases
6. Safety phrases
7. Batch identification
8. Reference to existing CSDS
9. Hazard classification		 not mandated. The UN RTDG label defines hazards by the use of symbols, colours and danger warning words for specific hazards (explosive, radioactive, corrosive, etc.). 1. Chemical identity
2. Hazard symbol and indication of danger
3. Risk phrases
4. Safety phrases
5. Supplier identification (full address and tel. No.)
6. EEC number if allocated
7. the wording "EEC label" where appropriate		 1. Chemical identity
2. Supplier identification
3. Appropriate hazard warnings

Employer must ensure that labels and other forms of warning are in English and may add other languages if appropriate.

 1. Supplier label:
-product identifier
-supplier identification
-reference to existing CSDS
-hazard symbols;
and for containers over 100 ml:
-risk and safety phrases
-first aid measures
2. Workplace label:
-product identifier
-information for the safe handling of the products
-reference to an existing CSDS.
-may contain WHMIS hazard symbols or other pictograms.
OTHER REQUIREMENTS Legibility, durability and size, uniformity of labels and symbols, including colours.In general, all containers of hazardous chemicals should at least indicate the hazards of the contents through appropriate wording or symbols. Placarding of transport units is defined, including form, minimum size and colour of placards. ANSI Standard Z-129.1.1988 defines acceptable precautionary phrases and hazard symbols. Chemical name may be replaced by generic name or number in the case of products covered by provisions on exemption for confidential business information.
Annex 1. Symbols and indications of danger
Annex 2. Risk phrases
Annex 3. Safety phrases
Annex 4. List of Substances with Risk and Safety Phrases Used in the Countries of EU
Annex 5. IARC list of carcinogens
Annex 6. List of chemicals, banned or severely restricted to certain uses
Annex 7. List of chemicals with potential to cause major hazard
Annex 8
A. General classification and labelling requirements for dangerous substances and preparations
B. Concentration limits to be used in applying the conventional method of assessing health hazard
Annex 9. United Nations Classification Recommendation on Transport of Dangerous Goods

BIBLIOGRAPHY

CLAYTON G.D. and CLAYTON F.E., ed., Patty's Industrial Hygiene and Toxicology, 3rd Revised Ed., John Wiley & Sons Inc., USA 1978

67/548/EEC Council Directive of 27 June 1967 on the approximation of laws, regulations and administrative provisions relating to the classification, packing and labelling of dangerous substances

This directive has been amended seven times and has eighteen adaptations to technical progress.

91/325/EEC Commission Directive of 1 March 1991 adapting to technical progress of the laws, regulations and administrative provisions relating to the classification, packing and labelling of dangerous substances

92/32/EEC Council Directive of 30 April 1992 amending for the seventh time Directive 67/548/EEC on approximation of the laws, regulations and administrative provisions relating to the classification, packing and labelling of dangerous substances

88/379/EEC Council Directive of 7 June 1988 on the approximation of the laws, regulations and administrative provisions of the Member States relating to the classification, packing and labelling of dangerous preparations

This directive has four adaptations to the technical progress.

90/492/EEC Commission Directive of 5 September 1990 adapting to technical progress for the second time Council Directive 88/379/EEC on the approximation of the laws, regulations and administrative provisions of the Member States relating to the classification, packing and labelling of dangerous preparations

2455/92/EEC Council Regulation of 23 July 1992 concerning the export and import of certain dangerous chemicals

91/338/EEC Council Directive of 18 June 1991 amending for the 10th time Directive 76/769/EEC on the approximation of the laws, regulations and administrative provisions of the Member States relating to the restrictions on the marketing of certain dangerous substances and preparations

76/769/EEC Council Directive of 27 July 1976 on the approximation of the laws, regulations and administrative provisions of the Member States relating to the restrictions on the marketing of certain dangerous substances and preparations

88/364/EEC Council Directive of 9 June 1988 on the protection of workers by banning of certain specified agents and/or certain work activities (Fourth individual Directive within the meaning of Article 8 of Directive 80/1107/EEC)

91/339/EEC Council Directive of 18 June 1991 amending for 11th time Directive 76/769/EEC on the approximation of the laws, regulations and administrative provisions of the Member States relating to the restrictions on the marketing of certain dangerous substances and preparations

91/659/EEC Commission Directive of 3 December 1991 adapting to technical progress Annex I to Council Directive 76/769/EEC on the approximation of the laws, regulations and administrative provisions of the Member States relating to the restrictions on the marketing of certain dangerous substances and preparations (asbestos)

GARDNER and COOKE, Chemical Synonyms and Trade Names, Technical Press, London

HEALTH and SAFETY COMMISSION, Information Approved for the Classification, Packing and Labelling of Dangerous Substances for Supply and Conveyance by Road, 2nd Ed., London 1988

ILO, International Labour Organisation, Code of Practice: Safety in the Use of Chemicals at Work, Geneva 1993

ILO, International Labour Organisation, Convention No. 170 Concerning Safety in the Use of Chemicals at Work, Geneva 1990

ILO, International Labour Organisation, Recommendation No. 177 Concerning Safety in the Use of Chemicals at Work, Geneva 1990

ILO, International Labour Organisation, Encyclopedia of Occupational Health and Safety, Vol I - III, Geneva 1983

ILO, International Labour Organisation, Major Hazard Control, A Practical Manual, 2nd Ed., Geneva 1990

ILO, International Labour Organisation, Occupational Cancer: Prevention and Control, Occupational Safety and Health Series 39, 2nd Ed., Geneva 1988

IPCS, International Programme on Chemical Safety, Chemical Safety, Fundamentals of Applied Toxicology, Training Module No 1, Geneva 1992

IPCS, International Programme on Chemical Safety, Environmental Health Criteria Series

IPCS, International Programme on Chemical Safety and CEC, Commission of the European Communities, International Chemical Safety Cards

National Board of Labour Protection, Finland, Dangerous Chemicals Classification, Warning Labelling, Material Safety Data Sheets, 1991

SAX N.I. and LEWIS R.J.Sr, Dangerous Properties of Industrial Materials, VII ed., Nostrand Reinhold Co., New York 1988

UNITED NATIONS, Transport of Dangerous Goods, 8th Ed., New York 1993 

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