The GHS OSHA Chemical Labeling Guide

Genesis of the Globally Harmonized System

• Protection will not be reduced
• The system will be based on intrinsic properties (hazards) of chemicals
• All types of chemicals will be covered
• All systems will have to be changed
• Involvement of all stakeholders should be ensured
• Comprehensibility must be addressed

GHS Implementation

• Proposed regulations released March 2013
• Final regulations released Jan 2014
• Implementation start date July 2015

Overview of GHS

• Defines criteria for health, physical and environmental hazards of chemicals
• Communicates hazard and precautionary information through labels and Safety Data Sheets (SDS).
• Provides explanatory information on how to apply the system

• Physical hazards
• Health hazards
• Environmental hazards

GHS Physical Hazards

• a gas is a substance or mixture which at 50° C has a vapor pressure greater than 300 kPa; or is completely gaseous at 20° C and a standard pressure of 101.3 kPa.
• a liquid is a substance or mixture that is not a gas and which has a melting point or initial melting point of 20° C or less at standard pressure of 101.3 kPa.
• a solid is a substance or mixture that does not meet the definitions of a liquid or a gas.

• Explosives¹². This class includes the following, either as is or as an article¹³:
  • An explosive substance (or mixture) is a solid or liquid which is in itself capable by chemical reaction of producing gas at such a temperature and pressure and at such a speed as to cause damage to the surroundings. Pyrotechnic substances are included even when they do not evolve gases.
  • A pyrotechnic substance (or mixture) is designed to produce an effect by heat, light, sound, gas or smoke or a combination of these as the result of non-detonative, self-sustaining, exothermic chemical reactions.
  There a six divisions within the Explosives Class.
• Flammable Gases¹⁴. Flammable gas means a gas having a flammable range in air at 20° C and a standard pressure of 101.3 kPa. Substances and mixtures of this hazard class are assigned to one of two hazard categories.
• Flammable Aerosols¹⁵. Aerosols, this means aerosol dispensers, are any non-refillable container made of metal, glass or plastics and containing any gas compressed, liquefied or dissolved under pressure with or without a liquid, paste or powder, and fitted with a release device allowing the contents to be ejected as solid or liquid particles in suspension in a gas, as a foam, paste or powder or in a liquid or gaseous state.
  Flammable aerosols are assigned to one of two categories on the basis of:
  • Its components
  • Its chemical heat of combustion, and if applicable
  • Results from the foam test for foam aerosols
  • Ignition distance test and enclosed space test for spray aerosols
• Oxidizing Gases¹⁶. An oxidizing gas is any gas which may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does. Substances and mixtures of this hazard class are assigned to a single hazard category.
• Gases under Pressure¹⁷. An oxidizing gas is any gas which may, generally by providing oxygen, cause or contribute to the combustion of other material more than air does. Substances and mixtures of this hazard class are assigned to a single hazard category.
• Flammable Liquids¹⁸. Flammable liquid means a liquid having a flash point of not more than 93° C. Substances and mixtures of this hazard class are assigned to one of four hazard categories on the basis of the flash point and boiling point. This class does not include aerosols, which should be classified as discussed above.
• Flammable Solids¹⁹. This class includes:
  • A flammable solid that is a solid that is readily combustible, or may cause or contribute to fire through friction.
  • Readily combustible solids that are powdered, granular, or pasty substances which are dangerous if they can be easily ignited by brief contact with an ignition source, such as a burning match, and if the flame spreads rapidly.
  Substances and mixtures of this hazard class are assigned to one of two hazard categories on the basis of test data²⁰. The tests include burning time, burning rate and behavior of fire in a wetted zone of the test sample.
• Self-reactive Substances and Mixturess²¹. Self-reactive substances are thermally unstable liquid or solid substances or mixtures liable to undergo a strongly exothermic thermal decomposition even without participation of oxygen (air). This definition excludes materials classified under the GHS as explosive, organic peroxides or as oxidizing. The following substances and mixtures are also excluded from this class:
  • Those whose heat of decomposition is less than 300 J/g; or,
  • Those whose self-accelerating decomposition temperature (SADT) is greater than 75° C for a 50 kg package.
  Substances and mixtures of this hazard class are assigned to one of seven “types, A to G” on the basis of the outcome of specific tests²² .
• Pyrophoric Liquids²³. A pyrophoric liquid is a liquid which, even in small quantities, is liable to ignite within five minutes after coming into contact with air. Substances and mixtures of this hazard class are assigned to a single hazard category on the basis of test data²⁴.
• Pyrophoric Solids²⁵. A pyrophoric solid is a solid which, even in small quantities, is liable to ignite within five minutes after coming into contact with air. Substances and mixtures of this hazard class are assigned to a single hazard category on the basis of test data ²⁶.
• Self-heating Substances and Mixtures²⁷. A self-heating substance is a solid or liquid, other than a pyrophoric substance, which, by reaction with air and without energy supply, is liable to self-heat. This endpoint differs from a pyrophoric substance in that it will ignite only when in large amounts (kilograms) and after long periods of time hours or days). Substances and mixtures of this hazard class are assigned to one of two hazard categories on the basis of test data²⁸.
• Substances which on Contact with Water Emit Flammable Gases²⁹. Substances or mixtures which, in contact with water, emit flammable gases are solids or liquids which, by interaction with water, are liable to become spontaneously flammable or to give off flammable gases in dangerous quantities. Substances and mixtures of this hazard class are assigned to one of three hazard categories on the basis of test results which measure the rate of flammable gas evolution³⁰.
• Oxidizing Liquids³¹. An oxidizing liquid is a liquid which, while in itself not necessarily combustible, may, generally by yielding oxygen, cause or contribute to the combustion of other material. Substances and mixtures of this hazard class are assigned to one of three hazard categories on the basis of test results which measure ignition or pressure rise time compared to defined mixtures³².
• Oxidizing Solids³³. An oxidizing solid is a solid which, while in itself not necessarily combustible, may, generally by yielding oxygen, cause or contribute to the combustion of other material. Substances and mixtures of this hazard class are assigned to one of three hazard categories on the basis of test results which measure mean burning time compared to specified control mixture³⁴.
• Organic Peroxides³⁵.An organic peroxide is an organic liquid or solid which contains the bivalent -0-0- structure and may be considered a derivative of hydrogen peroxide, where one or both of the hydrogen atoms have been replaced by organic radicals. The term also includes organic peroxide formulations (mixtures). Organic peroxides are thermally unstable substances and mixtures, which may:
  • Be liable to explosive decomposition;
  • Burn rapidly;
  • Be sensitive to impact or friction;
  • eact dangerously with other substances.
  Substances and mixtures of this hazard class are assigned to one of seven "Types A to G", on the basis of the results of specific tests³⁶.
• Corrosive to Metals³⁷. A substance or a mixture which is corrosive to metal is one which by chemical action will materially damage, or even destroy, metals. These substances or mixtures are classified in a single hazard category on the basis of tests on steel or aluminum when the surface corrosion rate exceeds 6.25 mm per year at a test temperature of 55° C³⁸.

GHS Health Hazards

• Acute Toxicity
• Skin Corrosion/Irritation
• Serious Eye Damage/Eye Irritation
• Respiratory or Skin Sensitization
• Germ Cell Mutagenicity
• Carcinogenicity
• Reproductive Toxicology
• Specific Target Organ Toxicity - Single Exposure
• Specific Target Organ Toxicity - Repeated Exposure
• Aspiration Toxicity

• Test data on the mixture
• Bridging Principles (explained below)
• Calculation methods. The particular calculation methods depend upon the specific health hazard endpoint and are found within the chapter covering each health hazard.

• Acute Toxicity³⁹. This GHS defines acute toxicity as those adverse effects occurring after oral or dermal administration of a single dose of a substance or mixture, or multiple doses given within 24 hours, or after an inhalation exposure or 4 hours. Substances are assigned to one of the five toxicity categories on the basis of LD50 (oral, dermal)⁴⁰ or LC50 (inhalation)⁴¹. The LC50 values are based on 4-hour tests in animals. However, the GHS provides guidance on converting 1-hour inhalation test results to a 4-hour equivalent.

  Acute toxicity	Cat. 1	Cat. 2	Cat. 3	Cat. 4	Category 5
  Oral (mg/kg)	≤ 5	> 5 ≤ 50	>50 ≤ 300	> 300 ≤ 2000	Criteria: Anticipated oral LD50 between 2000 and 5000 mg/kg; Indication of significant effect in humans;* Any mortality at class 4;* Significant clinical signs at class 4;* Indications from other studies.* *If assignment to a more hazardous class is not warranted.
  Dermal (mg/kg)	≤ 5	> 5 ≤ 200	> 200 ≤ 1000	> 1000 ≤ 2000
  Gases (ppm)	≤ 100	> 100 ≤ 500	> 500 ≤ 2500	> 2500 ≤ 5000
  Vapors (mg/l)	≤ 0.5	> 0.5 ≤ 2.0	> 2 ≤ 10	> 10 ≤ 20
  Dust & mists (mg/l)	≤ 0.05	> 0.05 ≤ 0.5	> 0.5 ≤ 1.0	> 1 ≤ 5

  In the US, OSHA is only regulating Categories 1-4. Category 5 would be used for consumer products.
• Skin Corrosion/Irritation⁴².
  • Skin Corrosion:The production of irreversible damage to the skin in at least 1 of 3 animals following the application of a test substance for up to 4 hours. Substances and mixtures in this hazard class are assigned to the single harmonized Category 1: Corrosive. In the case of transport, for example, this is further subdivided into Categories 1A, 1B, and 1C based upon the duration of the exposure, and allows assignment of the chemical or mixture into Packing Groups.
    To minimize animal testing, the GHS includes the following factors that should be evaluated beforehand and which can serve as the basis for classification:
    • Human experience showing irreversible damage to the skin;
    • Structure/activity or structure property relationship to a substance or mixture already classified as corrosive;
    • pH extremes of ≤ 2 and ≥ 11.5 including acid/alkali reserve capacity.
  • Irritation: The production of reversible damage to the skin following the application of a test substance for up to 4 hours. Chemicals or mixtures are assigned to Category 2 of this health hazard class if the Draize⁴³ score is ≥ 2.3 but < 4.0 or if it causes persistent inflammation. Those whose Draize score is ≥ 1.5 but < 2.3 may be assigned to Category 3 (Mild Skin Irritation).
    As with corrosive substances, human experience and structure/activity relationships should be considered in determining the potential for irritation before testing is initiated.
• Serious Eye Damage/Eye Irritation⁴⁴.
  • Serious Eye Damage: The production of tissue damage in the eye, or serious physical decay of vision, following application of a test substance to the anterior (front) surface of the eye, which is not fully reversible within 21 days of application. Substances and mixtures in this hazard class are assigned to the single harmonized Category 1
  • Eye Irritation: Changes in the eye following the application of a test substance to the anterior (front) surface of the eye, which are fully reversible within 21 days of application. Chemicals or mixtures are assigned to a single harmonized Category 2. However, the GHS provides some flexibility as follows: if the effects are fully reversible within 21 days they can be differentiated into Sub-Category 2A, or Sub-Category 2B if the effects are reversible in 7 days.
    As with skin corrosion/irritation, the GHS includes the following factors that should be evaluated before initiating testing, and which can serve as the basis for classification:
    • Human or animal experience indicating that the chemical or mixture is corrosive or irritating to eyes or skin;
    • Structure/activity or structure property relationship to a substance or mixture already classified as corrosive or irritating to eyes or skin;
    • pH extremes of ≤ 2 and ≥ 11.5 including acid/alkali reserve capacity.
    Note that for the first two factors listed above, effects on skin are deemed sufficient for classifying effects on the eye.
• Respiratory or Skin Sensitization⁴⁵.
  • Respiratory sensitizer: A substance that induces hypersensitivity of the airways following inhalation of the substance. Substances and mixtures in this hazard class are assigned to Category 1. The GHS does permit differentiation into Sub-Categories 1A and 1B, depending upon:
    • Frequency of occurrence in humans
    • Probability of a high vs. low to moderate sensitization rate occurrence in humans based upon animal data
    • Severity of reaction.
  • Skin sensitizer: A substance that will induce an allergic response following skin contact. The definition for "skin sensitizer" is equivalent to "contact sensitizer". Substances and mixtures in this hazard class are assigned to Category 1. As with respiratory sensitizers, this hazard class can be further differentiated into two sub-categories, based upon factors similar to those presented immediately above
• Germ Cell Mutagenicity⁴⁶ Mutagen means a chemical or mixture that can cause mutations⁴⁷ in the germ cells of humans that can be transmitted to their off-spring. . Substances and mixtures in this hazard class are assigned to one of two hazard categories. Category 1 has two subcategories:
  • Category 1A: Substances or mixtures known to induce heritable mutations. Assignment to this category is based upon human epidemiological studies.
  • Category 1B: Substance which should be regarded as if they induce heritable mutations in the germ cells of humans. Assignment to this category is based upon animal data, or human tests results that demonstrate mutagenic effects with no evidence of transmission to off-spring.
  Category 2 includes those substances which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans. Assignment to this category is based upon animal data, or in vitro tests.
• Carcinogenicity⁴⁸ Carcinogen means a chemical substance or a mixture of chemical substances which induce cancer or increase its incidence. Substances and mixtures in this hazard class are assigned to one of two hazard categories. Category 1 has two subcategories.
  • Category 1A: Substances or mixtures known to induce heritable mutations. Assignment to this category is based upon human epidemiological studies.
  • Category 1B: Substance which should be regarded as if they induce heritable mutations in the germ cells of humans. Assignment to this category is based upon animal data, or human tests results that demonstrate mutagenic effects with no evidence of transmission to off-spring.
  Category 2 includes those substances which cause concern for humans owing to the possibility that they may induce heritable mutations in the germ cells of humans. Assignment to this category is based upon animal data, or in vitro tests.
• Reproductive Toxicity⁴⁹ Reproductive toxicity includes adverse effects on sexual function and fertility in adult males and females, as well as developmental toxicity in offspring. Substances and mixtures with reproductive and/or developmental effects are assigned to one of two hazard categories, "known or presumed" and “suspected.” Category 1 has two subcategories for reproductive and developmental effects.
  • Category 1A: Known human reproductive toxicant. A substance in placed in this category largely based on human evidence.
  • Category 1B: Presumed human reproductive toxicant. Assignment to this category is largely based on animal evidence.
  Category 2 Suspected human reproductive toxicant. There is evidence from humans or experimental animals, possibly supplemented with other data, for a substance or mixture assigned to this category, but which is not sufficiently convincing to place it in Category 1.
  Materials which cause concern for the health of breastfed children have a separate category, Effects on or Via Lactation.
• Specific Target Organ Toxicity - Single Exposure⁵⁰ Substances and mixture that cause specific, non-lethal target organ toxicity arising from a single exposure are assigned to this hazard class. All significant health effects that can impair function, reversible and irreversible, immediate and/or delayed are included, with exception of those effects already covered in other chapters of Part 3. Classification depends upon reliable evidence that a single exposure of a substance or mixture has produced a consistent and identifiable toxic effect in humans, or an effect in experimental animals that has relevance for humans. Human data are the primary sources of evidence. Specific target organ toxicity can occur by any route of exposure, principally, oral, dermal, or inhalation.
  This hazard class is divided into three categories.
  • Category 1: Substances that have produced significant toxicity in humans, or that, on the basis of evidence from studies in experimental animals can be presumed to have the potential to product significant toxicity in humans following a single exposure. Classification depends upon reliable evidence that a single exposure of a substance or mixture has produced a consistent and identifiable toxic effect in humans, or an effect in experimental animals at low doses that has relevance for humans.
  • Category 2: Substances that, on the basis of evidence from studies in experimental animals can be presumed to have the potential to be harmful to human health following a single exposure. Placing a substance or mixture in this category generally depends upon reliable evidence that a single exposure of a substance or mixture in experimental animals at moderate doses has produced significantly toxic effects that have relevance for humans.
  • Category 3: Transient target organ effects. This category only includes narcotic effects⁵¹ and respiratory tract irritation.
• Specific Target Organ Toxicity - Repeated Exposure⁵² Substances and mixture that cause specific, non-lethal target organ toxicity arising from a repeated exposure are assigned to this hazard class. All significant health effects that can impair function, reversible and irreversible, immediate and/or delayed are included. As discussed above, those effects already covered in other chapters of Part 3 are excluded from this hazard class.
  This hazard class is divided into two categories.
  • Category 1: Substances that have produced significant toxicity in humans, or that, on the basis of evidence from studies in experimental animals can be presumed to have the potential to product significant toxicity in humans following repeated exposure. Assignment to this category depends upon reliable evidence in humans, or an effect in experimental animals at low doses that has relevance for humans.
  • Category 2: Substances that, on the basis of evidence from studies in experimental animals can be presumed to have the potential to be harmful to human health following repeated exposure. Assignment to this category generally depends upon reliable evidence that a repeated exposure of a substance or mixture in experimental animals at moderate doses has produced significantly toxic effects of relevance for humans.
• Aspiration Hazard⁵³ Aspiration is the entry of a substance or mixture, whether liquid or solid, directly through the oral or nasal cavity, or indirectly from vomiting, into the trachea and lower respiratory system. Aspiration toxicity includes severe acute effects such as chemical pneumonia, varying degrees of pulmonary injury or death following aspiration. This hazard class comprises two categories.
  • Category 1: Chemicals known to cause human aspiration toxicity hazards or to be regarded as if they cause human aspiration toxicity hazard. A chemical substance or mixture is assigned to this hazard class and category based upon reliable and good human evidence, or if it is a low viscosity hydrocarbon⁵⁴.
  • Category 2: Chemicals which cause concern owing to the presumption that they cause human aspiration toxicity hazard. In assigning a chemical or mixture to this category, animal studies and expert judgment are used, and take into account surface tension, water solubility, boiling point, and volatility. Kinematic viscosity can also be an indicator for this category.

Bridging Principles⁵⁵

• Dilution: If a mixture is diluted with a diluent that has an equivalent or lower toxicity, then the hazards of the new mixture are assumed to be equivalent to the original.
• Batching: If a batch of a complex substance is produced under a controlled process, then the hazards of the new batch are assumed to be equivalent to the previous batches.
• Concentration of Highly Toxic Mixtures: If a batch of a complex substance is produced under a controlled process, then the hazards of the new batch are assumed to be equivalent to the previous batches.
• Interpolation within One Toxic Category: Mixtures having component concentrations within a range where the hazards are known are assumed to have those known hazards.
• Substantially Similar Mixtures: Slight changes in the concentrations of components are not expected to change the hazards of a mixture and substitutions involving toxicologically similar components are not expected to change the hazards of a mixture.
• Aerosols: An aerosol form of a mixture is assumed to have the same hazards as the tested, non-aerosolized form of the mixture unless the propellant affects the hazards upon spraying.

GHS Environmental Hazards

Dangerous to the Aquatic Environment⁵⁶

• Acute (short term) aquatic toxicity
• Chronic (long term) aquatic toxicity
• Potential for or actual bioaccumulation
• Degradation (biotic or abiotic) for organic chemicals.

• Acute aquatic toxicity: The intrinsic property of a substance to harm an aquatic organism in a short-term exposure to it. The organisms typically tested are fish, crustacea, and algae since they are considered as surrogates for all aquatic organisms; other organisms may be considered. This hazard class is subdivided into three categories:

  Acute Category 1	L(E)C5057 ≤ 1.00 mg/l
  Acute Category 2	L(E)C50 > 1.00 but ≤ 10.0 mg/l
  Acute Category 3	L(E)C50 >10.0 but < 100 mg/l

• Chronic aquatic toxicity: The intrinsic property of a substance to cause adverse effects to aquatic organisms during aquatic exposures which are determined in relation to the life-cycle of the organism. Chronic toxicity data are generally less available than acute data, and the test methods for determining it are less standardized. This hazard class is subdivided into three categories and a “safety net” category (Chronic Category 4). The latter is used when available data do not allow classification under the criteria, but there are still concerns.
  Classification follows a tiered approach: First, determine whether available data is adequate for classification as a chronic hazard. If so, then classify into either two or three Chronic Categories, depending upon the how readily the substance degrades in the aquatic environment.

  Chronic Category 1	Chronic NOEC58 or ECx59 ≤ 0.1 mg/l Not rapidly degradable Chronic NOEC or ECx ≤ 0.01 mg/l Rapidly degradable
  Chronic Category 2	Chronic NOEC or ECx ≤ 1 mg/l Not rapidly degradable Chronic NOEC or ECx ≤ 0.1 mg/l Rapidly degradable
  Chronic Category 3	Chronic NOEC or ECx ≤ 1 mg/l Rapidly degradable

  If adequate chronic data are not available, then classification is accomplished by using information on acute aquatic toxicity data and environmental fate data (bioaccumulation and biodegradability).

  Chronic Category 1	Chronic NOEC58 or ECx59 ≤ 0.1 mg/l Not rapidly degradable Chronic NOEC or ECx ≤ 0.01 mg/l Rapidly degradable
  Chronic Category 2	Chronic NOEC or ECx ≤ 1 mg/l Not rapidly degradable Chronic NOEC or ECx ≤ 0.1 mg/l Rapidly degradable
  Chronic Category 3	Chronic NOEC or ECx ≤ 1 mg/l Rapidly degradable

  Mixtures are classified by a tiered methodology similar to that discussed above for health hazards:
  
  • Test data on the mixture
  • Bridging Principles (explained above under GHS Health Hazards)
  • Calculation methods: “Summation of classified ingredients” and/or an “additivity formula.” These calculation methods are detailed in the chapter. It is noteworthy that the summation method utilizes "multiplying factors" that are applied to highly toxic ingredients classified as Acute or Chronic 1. The more toxic the ingredient, the more weight is assigned to it in the calculation.

Hazardous to the Ozone Layer⁶²

Labeling⁶³

• Workplace
• Consumers
• Emergency Responders
• Transport

• Information should be conveyed in more than one way.
• Comprehensibility studies, both existing and in the literature, must be considered.
• The phrases used to indicate the degree of hazard should be consistent across all hazard classes. For example, flammability and carcinogenicity are very different hazard types, but a way needed to be found to put the degree of hazard into context and therefore convey the same degree of concern.

Safety Data Sheets⁶⁶

SDS Format

Highlights of the OSHA Final Rule

• An appropriate group of written, printed or graphic information elements concerning a hazardous chemical that is affixed to, printed on, or attached to the immediate container of a hazardous chemical, or to the outside packaging.
  rather than
  Any written, printed, or graphic material displayed on or affixed to containers of hazardous chemicals.

• Acute toxicity, Category 5
• Corrosion/Irritation, Category 3
• Aspiration toxicity, Category 2.

• "Hazardous chemical" means any chemical which is classified as a physical hazard or a health hazard, a simple asphyxiant, combustible dust, pyrophoric gas, or hazard not otherwise classified.

• Fall below the cut-off value/concentration limit of a hazard class; or,
• Fall under a GHS hazard category that has not been adopted by OSHA (e.g., acute toxicity Category 5).

• Hazards are classified, not evaluated.
• Classification criteria are revised
• Labeling provisions are revised to include standardized:
  • Signal words
  • Pictograms
  • Hazard statements
  • Precautionary statements
• Labels must be updated in 6 months
• "Floor" of hazardous chemicals is removed⁶⁹.
• The "one study" rule is revised⁷⁰.
• The 1% and 0.1% mixture rules are eliminated⁷¹.
• The Appendices are replaced and/or revised.

• • ACGIH TLVs
  • Information regarding carcinogenicity classifications by IARC and NTP
  • Hazard statements
  • Precautionary statements