Did you know workers in all industries are exposed to one or more workplace hazards every day? Workplace hazards are costly, but if the right precautions are taken, they can be prevented. Below are are the four common types of hazards you should be aware of at work. Show
Physical Hazards Ergonomic Hazards Chemical
Hazards Biological Hazards The biggest threat to worker health and safety is their work environment. Please take necessary precautions to protect yourself and your employees by maintaining a safe work environment. To learn more about workplace hazards, click here. OHC believes prevention is better than the cure. OHC can handle all of these types of hazards at one of our three locations. Visit occupationalhc.com to see how we can servce you. MOBILE OFFICE LOCATION PASCAGOULA OFFICE LOCATION 7. Chemistry Laboratory Safety SpecificationsIn this section: A. Hazard Communication Standard A. Hazard Communication Standard (HCS) to conform with the United Nations' (UN) Globally Harmonized System of Classification and Labeling of Chemicals (GHS) The Globally Harmonized System (GHS) is an international approach to hazard communication, providing agreed criteria for classification of chemical hazards, and a standardized approach to label elements and safety data sheets. The GHS was negotiated in a multi-year process by hazard communication experts from many different countries, international organizations, and stakeholder groups. It is based on major existing systems around the world, including OSHA's Hazard Communication Standard and the chemical classification and labeling systems of other US agencies. The result of this negotiation process is the United Nations' document entitled "Globally Harmonized System of Classification and Labeling of Chemicals," commonly referred to as The Purple Book. This document provides harmonized classification criteria for health, physical, and environmental hazards of chemicals. It also includes standardized label elements that are assigned to these hazard classes and categories, and provide the appropriate signal words, pictograms, and hazard and precautionary statements to convey the hazards to users. A standardized order of information for safety data sheets is also provided. These recommendations can be used by regulatory authorities such as OSHA to establish mandatory requirements for hazard communication, but do not constitute a model regulation. For additional information, go to the list of frequently asked questions. The three major areas of change are in hazard classification, labels, and safety data sheets.
The table below summarizes the phase-in dates required under the revised Hazard Communication Standard (HCS): Phase-in Dates Required under Revised Hazard Communication Standard
Back to top B. HazardClassifications: (The following information is from A Guide to The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) Classification is the starting point for hazard communication. It involves the identification of the hazard(s) of a chemical or mixture by assigning a category of hazard/danger using defined criteria. The GHS is designed to be consistent and transparent. It draws a clear distinction between classes and categories in order to allow for "self classification." For many hazards a decision tree approach (e.g., eye irritation) is provided in the GHS Document. For several hazards the GHS criteria are semi-quantitative or qualitative. Expert judgment may be required to interpret these data. Figure 3.1 Hazard Classification The term "hazard classification is used to indicate that only the intrinsic hazardous properties of substances and mixtures are considered and involves the following 3 steps: a) Identification of relevant data regarding the hazards of a substance or mixture; Figure 3.1 shows the harmonized definition for hazard classification, which can be applied to all hazard categories in the system. The data used for classification may be obtained from tests, literature, and practical experience. The GHS health and environmental hazard criteria/definitions are test method neutral. Accordingly, tests that determine hazardous properties conducted according to internationally recognized scientific principles can be used for purposes of hazard classification. The GHS endpoints that cover physical, health and environmental hazards are listed in Figures 3.2 and 3.3, respectively. As mentioned earlier, the GHS hazard definitions are criteria-based. The following information provides an overview of the GHS definitions and classification criteria. It is recommended that the person responsible for GHS implementation consult the GHS Document or "Purple Book" for more complete information. 3.1 What are the GHS Physical Hazards? The GHS physical hazards criteria, developed by the ILO and UNCETDG, were largely based on the existing criteria used by the UN Model Regulation on the Transport of Dangerous Goods. Therefore, many of the criteria are already being used on a worldwide basis. However, some additions and changes were necessary since the scope of the GHS includes all target audiences. The physical hazards classification process provides specific references to approved test methods and criteria for classification. The GHS physical hazard criteria apply to mixtures. It is assumed that mixtures will be tested for physical hazards. In general, the GHS criteria for physical hazards are quantitative or semi-quantitative with multiple hazard levels within an endpoint. This is different from several of the existing systems that currently have qualitative criteria for various physical hazards (e.g., organic peroxide criteria under WHMIS and OSHA HCS). This could make classification under the GHS more consistent. In developing GHS criteria for physical hazards it was necessary to define physical states. In the GHS,
The GHS physical hazards are briefly described below. For many of the physical hazards the GHS Document contains Guidance Sections with practical information to assist in applying the criteria. Figure 3.2 Physical Hazard
3.1.1 Explosives 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. Classification as an explosive and allocation to a division is a three-step process:
Table 3.1 Explosives
Explosive properties are associated with certain chemical groups that can react to give very rapid increases in temperature or pressure. The GHS provides a screening procedure that is aimed at identifying the presence of such reactive groups and the potential for rapid energy release. If the screening procedure identifies the substance or mixture to be a potential explosive, the acceptance procedure has to be performed. Substances, mixtures and articles are assigned to one of six divisions, 1.1 to 1.6, depending on the type of hazard they present. See, UN Manual of Tests and Criteria Part I Test Series 2 to 7. Currently, only the transport sector uses six categories for explosives. 3.1.2 Flammable Gases 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 on the basis of the outcome of the test or calculation method (ISO 10156:1996). 3.1.3 Flammable Aerosols Aerosols are any gas compressed, liquefied or dissolved under pressure within a non-refillable container made of metal, glass or plastic, with or without a liquid, paste or powder. The container is 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. Aerosols should be considered for classification as either a Category 1 or Category 2 Flammable Aerosol if they contain any component classified as flammable according to the GHS criteria for flammable liquids, flammable gases, or flammable solids. Classification is based on:
Aerosols are considered:
See the UN Manual of Tests and Criteria for the test method. 3.1.4 Oxidizing Gases Oxidizing gas means 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 on the basis that, generally by providing oxygen, they cause or contribute to the combustion of other material more than air does. The test method is ISO 10156:1996. Currently, several workplace hazard communication systems cover oxidizers (solids, liquids, gases) as a class of chemicals. 3.1.5 Gases under Pressure Gases under pressure are gases that are contained in a receptacle at a pressure not less than 280 Pa at 20°C or as a refrigerated liquid. This endpoint covers four types of gases or gaseous mixtures to address the effects of sudden release of pressure or freezing which may lead to serious damage to people, property, or the environment independent of other hazards the gases may pose. For this group of gases, the following information is required:
Criteria that use the physical state or compressed gases will be a different classification basis for some workplace systems. Table 3.2 Gases under Pressure
Data can be found in the literature, and calculated or determined by testing. Most pure gases are already classified in the UN Model Regulations. Gases are classified, according to their physical state when packaged, into one of four groups as shown in Table 3.2. 3.1.6 Flammable Liquids 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 (See Table 3.3). Flash Point is determined by closed cup methods as provided in the GHS document, Chapter 2.5, paragraph 11. Table 3.3 Flammable Liquids
3.1.7 Flammable Solids Flammable solids are solids that are readily combustible, or may cause or contribute to fire through friction. Readily combustible solids 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 (Table 3.4) on the basis of the outcome of the UN Test N.1 (UN Manual of Tests and Criteria). The tests include burning time, burning rate and behavior of fire in a wetted zone of the test sample. Table 3.4 Flammable Solids
3.1.8 Self-Reactive Substances Self-reactive substances are thermally unstable liquids or solids 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. These materials may have similar properties, but such hazards are addressed in their specific endpoints. There are exceptions to the self-reactive classification for material: (i) with heat of decomposition less thank 300 J/g or (ii) with self-accelerating decomposition temperature (SADT) greater than 75°C for a 50 kg package. Substances and mixtures of this hazard class are assigned to one of the seven 'Types', A to G, on the basis of the outcome of the UN Test Series A to H (UN Manual of Tests and Criteria). Currently, only the transport sector uses seven categories for self-reactive substances (Table 3.5). Table 3.5 Self-Reactive Substances
Pyrophorics 3.1.9 Pyrophoric Liquids 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 the outcome of the UN Test N.3 (UN Manual of Tests and Criteria). 3.1.10 Pyrophoric Solids 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 the outcome of the UN Test N.2 (UN Manual of Tests and Criteria). 3.1.11 Self-Heating Substances 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 the outcome of the UN Test N.4 (UN Manual of Tests and Criteria). 3.1.12 Substances which on Contact with Water Emit Flammable Gases Substances that, 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 (UN Test N.5 UN Manual of Tests and Criteria), which measure gas evolution and speed of evolution. Table 3.6 Substances which on Contact with Water Emit Flammable Gases
3.1.13 Oxidizing Liquids 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 (UN Test O.2 UN Manual of Tests and Criteria) which measure ignition or pressure rise time compared to defined mixtures. 3.1.14 Oxidizing Solids 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 (UN Test O.1 UN Manual of Tests and Criteria) which measure mean burning time and re compared to defined mixtures. Currently, several workplace hazard communication systems cover oxidizers (solids, liquids, gases) as a class of chemicals. 3.1.15 Organic Peroxides 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). Such substances and mixtures may:
Substances and mixtures of this hazard class are assigned to one of seven 'Types', A to G, on the basis of the outcome of the UN Test Series A to H (UN Manual of Tests and Criteria). Currently, only the transport sector uses seven categories for organic peroxides. Table 3.7 Organic Peroxides
3.1.16 Substances Corrosive to Metal A substance or a mixture that by chemical action will materially damage, or even destroy, metals is termed 'corrosive to metal'. These substances or mixtures are classified in a single hazard category on the basis of tests (Steel: ISO 9328 (II): 1991 - Steel type P235; Aluminum: ASTM G31-72 (1990) - non-clad types 7075-T6 or AZ5GU-T66). The GHS criteria are a corrosion rate on steel or aluminum surfaces exceeding 6.25 mm per year at a test temperature of 55°C. The concern in this case is the protection of metal equipment or installations in case of leakage (e.g., plane, ship, tank), not material compatibility between the container/tank and the product. This hazard is not currently covered in all systems. 3.2 What are the GHS Health and Environmental Hazards? The GHS health and environmental hazard criteria represent a harmonized approach for existing classification systems (see Figure 3.3). The work at the OECD to develop the GHS criteria included:
Figure 3.3 Health Hazard
Environmental Hazard
For additional information, check out OSHA's Web site. Back to top C. Ordering Chemicals – Safety Procedures: With the cost of shipping, storing and disposing of chemicals, planning for ordering of chemicals is critical. The following safety procedures are recommended for ordering practices:
Back to top D. Receiving Chemicals: Safety procedures for receiving shipments of chemicals and their use include the following:
Back to top E. Storage of Chemicals:
Back to top F. Handling and Using Chemicals:
Back to top G. Chemical Disposal:
Back to top H. Chemical Labeling-National Fire Protection Association (NFPA) System: The NFPA system of chemical labeling is characterized by a color coded diamond shaped symbol. It is designed to quickly identify safety hazards of the material and the degree of flammability, level of health and instability hazards. For a detailed explanation, visit the following Web sites: The NFPA's Hazard Rating Diamond NFPA 704 Hazard Rating System Back to top I. Chemical Labeling: Under the revised HCS, once the hazard classification is completed, the standard specifies what information is to be provided for each hazard class and category. Labels will require the following elements:
There are nine pictograms under the GHS to convey the health, physical and environmental hazards. The final Hazard Communication Standard (HCS) requires eight of these pictograms, the exception being the environmental pictogram, as environmental hazards are not within OSHA's jurisdiction. The hazard pictograms and their corresponding hazards are shown below.
For additional information, go to OSHA's Web site. Hazardous Materials Identification System HMIS Hazardous Materials Identification System (HMIS) was developed by the National Paint & Coatings Association (NPCA) in concert with OSHA’s HazCom Standard. It allows employees to quickly know the type and degree of hazards associated with the chemical being used. However, it is not designed for emergency information like the NFPA system. See the MSDS HyperGlossary and the American Coatings Association. Back to top J. Secondary Labels: If chemicals are transferred from a stock bottle into a smaller container, the latter is known as a secondary container. Although OSHA does not require labeling of the secondary container in all instances (e.g., one person filling a secondary container from a properly labeled primary container for one shift, one person use only operation) per the hazard communications standard, it is prudent safety practice in the laboratory to do so. A good start is placing the name of the chemical, NFPA label system information and date. Back to top K. Safety Data Sheets (SDS): The revised HCS requires that the information on the SDS is presented using consistent headings in a specified sequence. Paragraph (g) of the final rule indicates the headings of information to be included on the SDS and the order in which they are to be provided. In addition, Appendix D indicates what information is to be included under each heading. The SDS format is the same as the ANSI standard format which is widely used in the U.S. and is already familiar to many employees. The format of the 16-section SDS should include the following sections: Section 1. Identification Sections 12-15 may be included in the SDS, but are not required by OSHA. Exposure Limits: Exposure limits are designed to protect employees from excessive exposure to hazardous substances. The limits usually are relative to the concentration of a chemical in the air. However, they also may define limits for physical agents such as noise, radiation and heat. There are a variety of exposure limits established by professional safety organizations (American Industrial Hygiene Association), governmental organizations (OSHA, EPA) and chemical manufacturers. The information can usually be found on the SDS. Legal Limits: Permissible Exposure Limits (PELs) are established by OSHA, 29 CFR 1910.1000, and 1910.1001 through 1910.1450. They specify the maximum amount or concentration of a chemical to which a worker may be exposed. These are defined in three ways:
Other Exposure Limits (legally unenforceable):
Back to top L. Chemical Tracking System: Chemical tracking systems are a chemical database which is used to characterize the life of chemicals used in the laboratory. They should cover the history of the chemical. Remember that schools own the chemical from the cradle to the grave! There are various ways to set up these systems from index cards to a computer-based system. The following tracking fields are recommended:
Regularly scheduled inventory inspections should be conducted to delete any inaccurate data in the system and dispose of outdated, unneeded, or deteriorated chemicals following the written Chemical Hygiene Plan. Back to top M. Centrifuge Operation: Centrifuges are useful tools in the laboratory but need to be operated safely:
Back to top N. Electricity Hazards: Proper grounding of flammable solvent containers and equipment is needed to prevent protection from static electricity and sparks. Dry air or low humidity fosters static electricity dangers. Sources of sparks and discharges include:
Back to top O. Glassware Hazards: The leading cause of injury incidents in science laboratories usually involves the use of glassware. Borosilicate glassware is recommended for almost all laboratory work. The following procedures are recommended to reduce or eliminate injuries related to glassware in the chemistry laboratory:
What are the four categories of hazards OSHA has identified in laboratory setting?The laboratory environment can be a hazardous place to work. Laboratory workers are exposed to numerous potential hazards including chemical, biological, physical and radioactive hazards, as well as, musculoskeletal stresses.
What types of hazards should you protect yourself from in the laboratory?Are You Prepared for the Top 5 Laboratory Hazards?. Fire/Explosions. In a laboratory, all chemicals and liquids should be treated as if they are as potent as gasoline. ... . Thermal and Chemical Burns. ... . Skin Absorption of Chemicals. ... . Inhalation of Toxic Fumes. ... . Cuts to the Skin.. What are hazards define four sources of hazards?Hazards can be classified in several ways; they can be classified as natural, anthropogenic, technological, or any combination, such as in the case of the natural phenomenon of wildfire becoming more common due to human-made climate change or more harmful due to changes in building practices.
Which of the following may be considered a hazard in the laboratory?Laboratory hazards include not only chemical and biological hazards but physical hazards as well. These include, but are not limited to, slips, trips, and falls, sharps, compressed gases, pressurized equipment, electrical equipment, lasers, radiation, mechanical hazards, noise, and thermal hazards.
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