GHS system for classification and labeling of chemicals

What is the GHS system?

In an attempt to standardize and harmonize the classification and labeling of chemicals worldwide, the United Nations proposes the so-called Globally Harmonized System (GHS).[1] The aim is to develop a worldwide approach to the classification and labeling of chemicals. As well as a set of harmonized criteria on the hazard of chemicals.

With this system, the potential hazards of chemicals are defined and classified, in order to use these criteria in labeling and in the so-called Material Safety Data Sheets (MSDS). These MSDSs provide information on the hazards and risks of chemicals in handling, storage and transport.

The main objective of the GHS system is to improve the protection of human health and the environment through adequate information on the hazard of chemical compounds to both users and suppliers or transporters.

Hazard pictograms

One of the main elements within this GHS system are the so-called hazard pictograms, which consist of:

  • An icon or symbol. A total of nine standardized hazard symbols have been used. There are three groups that warn of physical hazards, human health hazards and environmental hazards.
    These icons are part of the set of symbols used in the United Nations Recommendations on the Transport of Dangerous Goods (Model Regulations) except for the symbol representing the health hazard, the exclamation mark and the fish and tree, which relates to the environment (see Table 1).
  • A geometric figure formed by a square resting on a vertex with a red border.
  • A legend formed by a series of signs and words of danger or warning, collected in the so-called "H-phrases", which are used in the labeling.


Table 1:Globally Harmonized System (GHS) icons.

Bomb explodingFlame
Flame on circleBottle of gas
CorrosionSkull & crossbones
Exclamation markHuman torso

The harmonized criteria allow:

  • Classify chemicals by the danger involved.
  • Label them using statements and world-standarized hazard pictograms.

GHS implementation has already started worldwide and many countries have already incorporated this system.

In Table 2, the pictograms are shown together with their legends that form the GHS system. The pictograms are composed of the aforementioned nine icons included in a square set on the apex, with a red border on a white background.


Table 2: Globally Harmonized System (GHS) pictograms.

GHS01 Danger, Unstable, ExplosiveGHS02 Danger, or Warning, Flammable
GHS03 Danger, or Warning, OxidizingGHS04 Warning, Compressed gas
GHS05 Danger, or Warning, Corrosive cat. 1GHS06 Danger, Toxic cat. 1-3
GHS07 Warning, Toxic cat. 4, Irritant cat. 2 or 3, Lower systemic health hazardsGHS08 Danger, or Warning, Systemic health hazards
GHS09 Warning, (for cat. 1), (for cat. 2 no signal word), Environmental hazard

In addition, the format of chemical product labels has been standardized. Each label contains a product identifier, a pictogram, an identification word, a hazard phrase, and supplier information. Chemical manufacturers or suppliers may provide additional information on the label. The category designation is a letter or a number, shown in Table 4 and are included on the MSDS. There are nine pictograms and two words Danger or Warning. Examples of warning phrases are May cause respiratory irritation, Toxic in contact with skin or Heating may cause fire or explosion. The nine GHS hazard pictograms are depicted in Table 2. In addition, there is another group of pictograms that are used for transport (see Table 3).

Table 3: GHS system pictograms used for transportation.

Hazard statements (H-phrases)

Hazard statements or "H-phrases"[2] are phrases assigned to a hazard class or category, describing the nature of the hazards of a substance and, where appropriate, the degree of danger. They are part of the GHS system, to standardize a set of phrases relating to the dangerous chemicals that can be translated into different languages. The United Nations has published the list of "H-phrases" in all official languages.

Each "H-Phrase" is associated with a code beginning with the letter H and followed by three digits. Sentences corresponding to related hazards are grouped together with a code number, therefore the numbering is not consecutive. The code is used as a reference, and it is the phrase itself that must appear on labels and MSDSs.

Table 4 lists the different "H-phrases" codes (see corresponding links) grouped according to three categories: physical hazards (39 codes), health hazards (35 codes) and environmental hazards (8 codes).


Table 4: List of «H-phrases» codes.

Physical Hazards
H227, H205no pictogram
H200, H201, H202, H203, H204, H240
H206, H207, H208, H220, H221, H222, H223, H224, H225, H226H228, H229, H230, H231, H232, H242, H250, H251, H252, H260, H261
H270, H271, H272
H282, H283
H280, H281, H284

Health Hazards
H303, H313, H316, H320, H333, H362no pictogram
H300, H301, H310, H311,  H330, H331,
H302, H312, H315H317, H319, H332H335, H336
H304, H305, H334, H340, H341, H350, H351, H360, H361H370, H371, H372, H373
H314,  H318
Environmental Hazards

H401, H402, H413, H412no pictogram
H400H410, H411

Country-specific hazard statements

The European Union has implemented the GHS through the CLP Regulation. There are 24 other codes that can be added to the labeling and that provide supplementary information on the above-mentioned Hazards. A list of the various codes is summarized in Table 5.

Table 5: EU Hazard statements.

Physical propertiesEUH-001, EUH-014, EUH-018, EUH-019, EUH-044
Health propertiesEUH-029, EUH-031, EUH-032, EUH-066, EUH-070, EUH-071
Environmental propertiesEUH-059
Other EU hazard statements
EUH-201, EUH-201A, EUH-202, EUH-203, EUH-204, EUH-205, EUH-206, EUH-207, EUH-208, EUH-209, EUH-209A, EUH-210, EUH-401 

Precautionary statements (P-phrases)

In addition to the supplementary information on hazards, precautionary statements have been drawn up with the following codes (see corresponding link for additional information):

P100 – GENERAL precautionary statements

P101, P102, P103

P200 - PREVENTION precautionary statements

P201, P202, P210, P211, P220, P222, P223, P230, P231, P231+P232, P232, P233, P234, P235, P240, P241, P242, P243, P244, P250, P251, P260, P261, P262, P263, P264, P270, P271, P272, P273, P280, P282, P283, P284

P300 - RESPONSE precautionary statements

P301, P301+P310, P301+P312, P301+P330+P331, P302, P302+P334, P302+P352, P303, P303+P361+P353, P304, P304+P340, P305, P305+P351+P338, P306, P306+P360, P308, P308+P313, P310, P311, P312, P313, P314, P315, P320, P321, P330, P331, P332, P332+P313, P333, P333+P313, P334, P335, P336, P337, P337+P313, P338

P400 - STORAGE precautionary statements

P340, P342, P342+P311, P351, P352, P353, P360, P361, P362, P363, P370, P370+P376, P370+P378, P370+P380+P375, P371, P371+P380+P375, P372, P373, P375, P376, P377, P378, P380, P381, P390, P391, P401, P402, P402+P404, P403, P403+P233, P403+P235, P404, P405, P406, P407, P410, P410+P403, P410+P412, P411, P412, P413, P420

P500 - ELIMINATION precautionary statements


Material safety data sheets (MSDS)

Safety data sheets are also referred to as MSDSs. It is a document that provides detailed information on chemicals. It also includes a description of the precautions to be taken for handling and immediate emergency measures for such products. Additionally, they include their potential risk of physical harm to humans and the environment.

They contain information of vital importance for the transport of these dangerous goods and for the handling of these goods by laboratory personnel.

Thus, these sheets offer information on control and prevention measures. Therefore, the purpose of this information is to reduce the risk of accidents to both people and the environment.

In every laboratory, it is mandatory to have the corresponding data sheets. These must be prepared by the manufacturer of the chemical products and kept up to date. Moreover, the format of these data sheets varies depending on the manufacturer or the legislation of the different countries. In addition, many products are required to include the product safety record on the label.


References and notes

[1] The GHS was originated from Chapter 19 of Agenda 21, aproved at the United Nations Conference on Environment and Development (UNCED, 1992) and adopted in 2002.

[2] The "H-phrases", are included in Annex III of Regulation 1272/2008. Since June 1, 2015, this regulation will repeal Directive 67/548/EEC.