Introduction
The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) is an international system that is used in standardizing the classification and labeling of chemicals. The GHS describes the hazards of chemicals to health, environment, and body (Roughton & Crutchfield, 2008).
It also used in classification of other materials when they are compared with the other known hazardous chemicals. The GHS also assists in communicating information about hazardous chemicals including the protective measures needed to be taken that are placed on the labels and safety Data Sheets also known as the SDS.
The GHS is important, because the information it gives is used in determination of hazardous chemicals as well as gives information about what is needed to prepare a label or the SDS when needed. Its application (GHS) is of benefit to governments and companies as well as the workforce and the public.
According to researchers, using the GHS helps to lower the costs of healthcare, offer a safer working environment, increased efficiency, and lastly disseminating knowledge about hazardous materials and chemicals that a person can come into contact. (Roughton & Crutchfield, 2008).
The GHS method of classifying chemicals is used worldwide as a tool of creating a standard advancement in understanding dangerous chemicals and their properties. It provides a guideline and a mechanism that details how to use safely dangerous chemicals as well as how to transport and dispose of the chemicals. People also use the GHS to learn about the effects and precautions that are needed when handling hazardous chemicals.
With the adoption and implementation of the safety data sheets in many work places, knowledge about the dangers of chemicals is becoming more accessible and this has helped in formulating preventive and protective measures aimed at improving the health and safety of the work places. This paper will look at the history of the GHS, hazard classification of materials, testing requirements, and finally implementation.
Discussion
History
The Globally GHS was created by the United Nations. It is an internationally agreed system of identifying and categorizing hazardous chemicals. The system was made to replace the many standard of classification that was being used in different countries. It was intended to introduce constituent criteria for labeling and classifying chemicals worldwide.
Development of the GHS began in 1992 at the Rio Conference, when various organizations such as the International Labor Organizations and government stakeholders met at a United Nations Conference (United Nations, 2005).
Before it was instituted by the United Nations, different countries had different methods for identifying chemicals and their regulations differed. Although in part the systems were similar, they always resulted in creating multiple standards for classifications and labeling of essentially the same hazardous chemicals in different countries (United Nation, 2010).
This difference in classification and labeling standards in different countries posed a great challenge to importation and exportation of hazardous chemicals. The system was and is meant to replace the different systems that are found in different regions. Although the GHS is not mandatory under the UN laws, the system helps participating countries by offering the infrastructure needed in its implementation. This has been very helpful especially to developing countries who cannot meet the cost of the infrastructure.
During the 1992, United Nation Conference at Rio members agreed that there was need for a harmonized system. They said in a statement that, “A globally harmonized hazard classification and compatible labeling system, including material safety data sheets and easily understandable symbols, should be available if feasible, by the year 2000” (PHMA, 2010).
Hazard Classification of Materials
Under the GHS classification of hazardous materials (substances and mixtures), three steps are followed:
- Identification of relevant data regarding the hazards of a substance or mixture;
- Subsequent review of those data to ascertain the hazards associated with the substance or mixture; and
- A decision on whether the substance or mixture will be classified as a hazardous substance or mixture and the degree of hazard, where appropriate, by comparison of the data with agreed hazard classification criteria (United Nations, 2006).
The criterion that is used by the GHS to classify hazardous material can be summarized as follows.
Physical Hazards
The Physical hazards are identified and classified based on the ststem used by the UN in identification of these goods. Below are some of the substances labeled as hazardous and their definitions.
- Explosives– under the GHS explosives are divided into six groups depending on how hazardous they are. The classification is adopted from the UN Dangerous Goods system.
- A Flammable Gas– under the GHS this is a gas that will burrn at temperatures below 20 °C when exposed to the air and their pressures are around 100 Kpa. The products or materials that are in this group are classified into either a one or two hazard category based on the results gotten after calculations.
- Flammable Aerosols– these are placed either under the category one or category two if their composition contains a component that is flammable. These can either be flammable solids , liquids or gasses.
- Oxidizing Gases these are gases that will release oxygen. they either cause or increase the rate at which substances are going to burn. The materials in this category are put under one class of category based on their ability to support ignition and fires.
- Gases under Pressure – thisare gases that are placed in counters that have very high pressures. They are also those gases that are stored as liquefied gases. The GHS considers them hazardous because if they are suddenly released they can cause physical damage or freezing. Their damage can extend to bodily harm, property and the environment.
- A Flammable Liquid liquids in this category will have their flash points at below 93°C. these products under this class will be placed in four groups according to the boiling and flash points they have.
- A Flammable Solid these are solids that are going to ignite if they are moved just a little or they experience friction. Under this are powdered or granular in nature. They will be easily ignited when they come into contact with open flames and ignition sources.
- Self-Reactive Substances- these are mostly unstable liquids or solids that are going to heat up and burn even in closed containers. They do not require air to burn, excluded in this category are the explosives and oxidizing substances (United Nations, 2006).
Others include, Pyrophoric Liquid, Pyrophoric Solid, Self-Heating Substances, Oxidizing Liquids, Oxidizing Solids, Organic Peroxides, Substances Corrosive to Metal, and Substances which on Contact with Water Emit Flammable
Health Hazards
Several substances have been labeled as being health hazards under the GHS. According to the GHS, they are identified by the effect they have on the health of a living thing.
- Acute Toxicity– substances and mixtures under this are placed under five categories. From these categories people can know what is required for protection, transportation and handling.
- Skin Corrosion – the term is used to refer to situations where the damage to the skin is irreversible after a person has been in contact with the chemical or substance for a substantial amount of time. Materials under this category are placed into one category known as the corrosion category.
- Skin Irritation the term is used to refer to situations when a person gets into contact with a substance and the damage they suffer on their skin is reversible.. These substances are placed under a special category of irritants.,but for some products there are other categories that can be applied such as mild irritants.
- Serious Eye Damage. This means that the damage caused by the substance or mixture affects the eye and the damage done is irreversible within a time frame of 21 days afte coming into contact. Materials that are in this category are classified under a single category that is harmonized.
- Eye Irritation this means that the damage caused to the eye can be reversed with in a time frame of 21 days after being into contact with the hazardous material. Marterials and products under this are placed under categories of irritation, but for special occasion and after application from relevant authorities products can be placed under special categories according to the severity of the damage they can cause.
- Respiratory Sensitizer the term will be used to refer to products that are going to cause hypersensitivity while breathing. It is characterized by wheezing and sneezing. This will in turn cause difficulty in breathing after the substance has been inhaled. Materials and roducts under this are placed under a single hazard category.
- Skin Sensitizer. This term under the GHS is used to refer to all substances and mixtures that are going to cause an allergic reaction after coming into contact with the skin. Another term for this is contact sensitizer. Materials and products under this are placed under a single category of hazardous products.
- Germ Cell Mutagenicity. The term is used to refer to the rise and increase of mutations of living cells. Materials and substances that cause these mutations are placed under two categories. This is according to the severity of the mutation they are going to cause after coming into contactn(United Nations, 2006).
Other definitions include, Reproductive Toxicity, Target Organ Systemic Toxicity (TOST), Aspiration Hazard, and Carcinogenicity.
The Environmental Hazards
They are classified according to their toxicity as follows
- Acute Aquatic Toxicity. Under the GHS the term is used to refer to the intrinsic property of a substance or mixture to cause harm or injury to animals and organisms in water after being exposed for a short time. There are three levels of toxicity under the GHC. These are based on available data on toxicity of substances. In some regions the levels and categories will be extended into various sectors such as fishing, hotels etc.
- Chronic Aquatic Toxicity– the term is used to refer to the potential or properties of substances and mixtures to affect the aquatic living organisms after being exposed. The effects are measured in relation to the organism’s lifecycle. The level of toxicity determines the categorization of these substances. There are four categories that are available under this (United Nations, 2006).
Hazardous Classification of Mixtures Under the GHS protocol
Under the GHS system mixtures are tested to see their effect on the environment and the health of organisms. This is based on the information that is available concerning the effect of the mixture and the substances or subcomponent of it. The practice used in identifying hazardous mixtures is borrowed from the EU system used in preparing mixtures and classifying them.In summary, the classification of mixtures under the GHS is based on the following three steps.
- If there is data available regarding the toxicological or the ectoxicological aspect of the substance, then it is used in the identification and classification process.
- A bridging principle is undertaken when the data on this mixtures is not available. It tests the individual property of the components making the mixture.
- If both data for the mixture and the bridging principle cannot be applied, then a calculation or cut off values that is described in the specific end point is used in the classification of the mixture.
Requirements needed for testing
The guideline that is used in the GHS does not give information on how substances are going to be tested if they are hazardous or not. This is because GHS tries as much as it can to avoid using animals to test the materials and prefer other methods applied in the science world.
This means that the determination of health and environmental hazards is based on various scientific methods that are based on international procedures and criteria already approved in different systems. the test data that is available from different sources is used when classifying hazardous materials in different regiosns is adopted and encouraged.
This thereby avoids the need for animal testing. Under the GHS, materials are tested to see if they are physical hazards by using various test methods used by the UN. The tests for mixtures are also based on the same rules.
When substances or mixtures have been ascertained to be hazardous according to the GHs, the information is supposed to be passed or communicated to relevant people including authorities and those that will be using the material.
The methods used to communicate this messages are essentially the same as those used in other systems only that the GHS is internationally accepted. The GHS standards are put in place to help people and users to understand the things they need to do to protect themselves. The guiding principles used under the GHS are,
- Although business information and trade secterts are important in business they should not put the lives of workers at risk.
- The information transmitted should be placed in different modes such as labels and placards.
- The messages should be written in a language and a way that an average person can understand easily.
- The information passed should contain a hazard statement as well as a statement that details the precautions that are needed..
- The information should be consistent to each other to avoid confusion in interpretation and understanding.
- The communication should take into consideration all research and any new evidence that has been carried out.
Some of the factors that affected the work included the comprehensibility of the labels because of difference in culture and language. Other factors that affected the work included
- Philosophies were sifferent in the systems being used regarding the things that were to appear on the labels.
- Ability to translate the phrases that were used
- Ability to appropriately understand the meaning and respond to the symbols or pictograms used
These factors were considered when the GHS communication tools were being developed. The GHS developed the GHS purple book that gave a comprehensibility instrument to guide in formulating the labels.
Label elements
The standard label developed by the GHS includes the following.
- Symbols: the symbols transmit information on the healthbodily, and the environmental hazard information about the substance or mixture. They also include the GHS hazard class and category associated with the material. The pictures used should include also the harmonized symbol and other elements such as background and pattern. The symbols are borrowed from the EU system.
- Signal Words: include warning and danger words. These are used to emphasize hazards associated with the product. They are used to show the people the severity of the product they are using so that they can take the measures that are needed in handling it. The GHS says that only one of these signal words can be placed on a label so that confusion can be reduced.
- Hazard Statement: this is a statement that is placed on a label and will be used mostly on products that have more than one risk. It will help people to identify potentially more dangerous substances. This is used to help people identify the hazardous substances and mixtures.
The other additional label elements that are included according to the GHS are Precautionary Statements, Product Identifier, Supplier identification and, Supplemental information.
Implementation of the GHS
The implementation and adoption of the GHS is expected to help in making the international trade efficient. This going to be helpful in different countries that presently use different methods to communicate the hazard information of products. The implementation of the GHS has not been put on a time frame, but the goal of the United Nation was to have it adopted by many countries by the end of 2008. Different countries require different schedules to update and implement the GHS system and conform to the standards.
For example, on United States published in an article that was going to guide the country in adoption of the GHS. This was based on based on the Directive 67/548/EEC and needed to have it changed to conform to the GHS.
The new regulation was expected to be passed by 2009 and to be adopted between 2010 and 2015. Australia expects to have the new regulations in place by the end of 2012. The United Nations monitors progress made by countries in implementing the GHS and it publishes summaries of the current status (United Nations, 2005).
References
PHMA. (2010). Global Harmonization of Hazard Classification and Labeling Systems. Web.
Roughton, J. E & Crutchfield, N. (2008). Job hazard analysis: a guide for voluntary compliance and beyond : from hazard to risk : transforming the JHA from a tool to a process Chemical, Petrochemical & Process. Boston: Butterworth-Heinemann.
United Nation. (2010). Resolutions and Decisions of the Economic and Social Council. New York : United Nations.
United Nations. (2004). A Guide to The Globally Harmonized System of Classification and Labelling of Chemicals (GHS). Web.
United Nations. (2005). Achieving the internationally agreed development goals: dialogues at the Economic and Social Council. New York : United Nations.