Material Safety Data Sheets (MSDSs)
An MSDS is a technical bulletin detailing information about a hazardous chemical. Every chemical manufacturer or importer must develop or obtain an MSDS for each hazardous chemical it supplies (29 CFR 1910.1200(g)). Distributors also must provide MSDSs to other distributors and commercial purchasers of their hazardous chemicals. As an employer, LBNL must provide MSDSs for each hazardous chemical in the workplace. The OSHA Laboratory Standard (see section on Laboratories) incorporates the Hazard Communication Standard’s laboratory requirements regarding retention of labels and MSDSs. These provisions require that MSDSs for hazardous chemicals received with incoming shipments be maintained and made readily accessible to employees, and that labels not be removed or defaced unless immediately replaced with other appropriate ones. The Lab has developed an electronic MSDS database for employees to access.
The federal Standard is designed so that the MSDS is the most comprehensive source of written information for the employee. No standard format for the MSDS is specified but all required information must be included. The MSDS must be written in English and, at a minimum, must contain the following:
•the identity (any chemical or common name) that is used on the container label;
•the chemical and common name of all ingredients having known health hazards if present in concentrations greater than 1%, and for carcinogens, if present at 0.1% or more;
•the physical and chemical characteristics of the hazardous components;
•the physical and health hazards, including signs and symptoms of exposure and prior and/or existing contra-indicating medical conditions;
•the primary routes of entry;
•any known exposure limits (OSHA PELs or ACGIH TLVs);
•whether the hazardous chemical is listed in the NTP Annual Report on Carcinogens or is a potential carcinogen according to IARC or OSHA;
•precautions for safe handling and use, and procedures for spill/leak cleanup;
•control measures;
•emergency first aid procedures;
•date of preparation, and
•the name, address, and telephone number of the company or the responsible employee distributing the MSDS.
When an MSDS is prepared, the chemical has to be evaluated based on the mandatory hazards determination requirements. When uncertainty exists concerning a chemical’s hazards, the preparer should be conservative in the evaluation to ensure employee protection.
How to Read an MSDS
When reading an MSDS, please keep in mind that:
•At times, the MSDS may outline only the minimum precautions for safe handling of the chemical in the sections on fire and explosion hazards, spill or leak procedures, special protection information, and special precautions. Thus, if employer policy or the reader’s judgment suggests more stringent procedures, they should be used.
•When no mention of a particular health effect is made in the MSDS, it should not be assumed that the substance is hazard-free. Test results may not have been available when the MSDS was prepared; testing of the substance is not required to create an MSDS.
•You should expect a completed MSDS with no blank spaces. If an MSDS with blank spaces is received, the supplier should be questioned. If certain data are not available, the MSDS should state so in the space provided.
•In many cases, the emergency first aid procedures and handling precautions are written to deal with a worst-case scenario, such as extensive exposure. Knowing this fact, you may believe, for a seemingly minor incident, that immediate medical attention is not required even though it is called for by the MSDS. Please keep in mind that in the absence of an informed opinion by a designated health professional, a prudent response is the best policy.
•It is important to check the date when the MSDS was prepared.
•Out-of-date MSDSs may not be reliable.
The purpose of the MSDS is to provide vital information on health and physical hazards. This part of the program will illustrate and describe each section of the MSDS to help you understand the data. You can use this information to plan training programs and to explain the MSDS to your employees. Some of the terms on the MSDS are quite technical; refer to the Glossary of Terms (Appendix 13) for help.
The MSDS must include, at a minimum, all eight of the described sections. The style and layout may vary. However, every section must be filled in, even if the item is not applicable (indicated by “N/A”). There should be no blank spaces. Note that some of the information, such as the chemical family, may be included but is not required. Remember that the information on the MSDS is prepared by the manufacturer of the product. Therefore, some data sheets contain excellent information, some are adequate, and others are poor. Other sources of data on toxic and health effects should be consulted for more complete information.
Product Identity
Identity: The name of the product as it appears on the label. A product may be a mixture of two or more chemicals.
Manufacturer’s name, address, and phone number: Self- explanatory. If the data comes from a source other than the manufacturer, the actual source must be indicated. The date of preparation or revision must be indicated.
Emergency telephone number(s): 24-hour number(s) that the manufacturer provides, so that emergency information can be obtained (e.g., medical emergencies).
Chemical family: The general class of compounds to which the hazardous substance or mixture belongs (e.g., ethers, acids, ketones, solvents). This term does not give you the exact content of the product.
Formula: The chemical formula may be given for single elements and compounds (e.g., sulfur dioxide (SO2), formaldehyde (HCHO)). This is not the formulation for mixtures.
Hazardous Ingredients
If the product is a mixture, all hazardous ingredients must be listed. However, ingredients that are not hazardous, or make up less than 1% of the product (less than 0.1% for carcinogens), do not have to be reported.
Exposure standards, i.e., Threshold Limit Value (TLV) and Permissible Exposure Limit (PEL) are included in this section, or under Health Hazards. Note that the higher the number for a TLV or PEL, the less hazardous the substance. See the Glossary for definitions of TLV and PEL.
The % column is intended to show the approximate percentage by weight or volume of each hazardous ingredient compared to the total weight or volume of the product. Normally, percentages will be listed to the nearest 5%. When the substance constitutes less than 5% of the product, this is indicated.
CAS number: The Chemical Abstract Service registry number identifies specific chemicals only, not mixtures; it is optional.
Physical Data
This section contains very important data to help predict the behavior of the material in experimental situations. The information provided is for the material as a whole, rather than for each hazardous ingredient. Vapor pressure, vapor density, % volatiles, and evaporation rate all basically tell you the same thing: whether breathing the vapors will be a problem, thus indicating the need for proper ventilation.
Boiling point: The temperature at which a liquid changes to a vapor at a given pressure; usually in degrees Fahrenheit (oF) at the sea-level pressure of 760 millimeters of mercury (mm of Hg). For mixtures, the initial boiling point or the boiling range may be given. A low boiling point may be a special fire hazard.
Vapor pressure: Refers to the pressure exerted by a saturated vapor above its own liquid, usually stated in mm of Hg at 25oC (77oF). The lower the boiling point, the higher the vapor pressure. A high vapor pressure indicates easy evaporation.
Vapor density: Tells whether the material is heavier or lighter than air. This is useful information to indicate a confined-space hazard. If heavier than air, the material will concentrate in low places, such as floors, elevator shafts, sewers, or the bottom of tanks.
Percentage volatility by volume: How much of the material evaporates at room temperature. A substance that is 100% volatile will evaporate completely, leaving no residues.
Evaporation rate: The rate at which the material will evaporate when compared to the rate of evaporation of a known material, usually butyl acetate. If another material is used for comparison, it should be indicated. If the number is greater than 1, the product evaporates more easily than the comparison material.
Solubility in water: The percentage of a material (by weight) that will dissolve in distilled water, at room temperature.
Specific gravity: The ratio of the weight of a volume of material to the weight of an equal volume of water. For insoluble materials, a specific gravity of less than one means the material is lighter than water and will float. Greater than one means that it sinks in water.
Melting point: The temperature at which a solid becomes a liquid under normal room conditions.
Appearance and odor: A brief description of the material at normal room temperature and atmospheric conditions. Do not rely on odor to alert you to a dangerous exposure. Some substances can reach hazardous levels and have no noticeable odor.
Fire and Explosion Hazard Data
This section should clearly indicate whether the material is flammable. If it is flammable, make sure there are no ignition sources nearby and that you have the correct fire extinguisher on hand. If you work with solvents, peroxides, explosives, metal dusts, or other unstable substances, this section is very important.
Flash point: The lowest temperature at which the material gives off enough vapor to ignite; this will help determine storage and handling procedures. The method used to obtain this information should be stated (e.g., closed cup).
Flammable or explosive limits: The range over which a flammable vapor, when mixed with the proper proportions of air, will flash or explode if ignited. The range is designated by lower explosive limit (LEL) and upper explosive limit (UEL), and is expressed in percentage of volume of vapor in the air.
Extinguishing media: Indicates what type of fire extinguisher to use, such as water, fog, foam, alcohol foam, carbon dioxide, or dry chemical.
Special firefighting procedures: Special handling procedures, personal protective equipment, and unsuitable firefighting substances should be listed. For example, water should not be used on fires involving reactive metals. General firefighting methods are not described.
Unusual fire and explosive hazards: Hazards that might occur as a result of overheating or burning of the material, including any chemical reactions or change in chemical form or composition.
Reactivity Data
This section indicates how unstable the substance is and lists conditions to avoid in order to prevent dangerous reactions. This information will help you handle and store the material properly.
Stability: The checked box will indicate whether the material is stable or unstable and under what conditions instability occurs.
Incompatibility: Lists materials and conditions to avoid. Such conditions may include extreme temperatures, jarring, or inappropriate storage. This is important to determining what other chemicals the material can be stored or used with.
Hazardous decomposition products: A list of the hazardous materials that may be produced if the material is exposed to burning, oxidation, heating, or certain chemical reactions. The product shelf life should be included, when applicable.
Hazardous polymerization: Polymerization is a chemical reaction in which two or more molecules of a substance combine to form repeating structural units of the original molecule. A hazardous polymerization causes an uncontrolled release of energy (heat). If this reaction can occur, it must be indicated.
Health Hazard Data
This section lists routes of entry (inhalation, skin absorption, ingestion), and gives signs and symptoms of overexposure, such as skin rash, tremors or dizziness. Short-term (acute) and long-term (chronic) health hazards, such as the ability to cause cancer (carcinogenicity), birth defects (teratogenicity), or “target organ” damage, should be listed. Some products cause both types of effects. Unfortunately, this important section often lacks adequate information, especially on the health effects of long-term exposure.
Instructions for first aid and emergency procedures for victims of acute inhalation, ingestion, or skin or eye contact must be included. Medical conditions that can be aggravated by exposure must also be detailed.
Information on exposure standards, such as TLV, PEL, or STEL, and toxicity data (indicated by an LD50 number), may be included here. Toxicity data is only an estimate of the degree of toxicity, based on experiments with test animals.
Precautions for Handling
This information will help you prepare for emergencies by having the proper materials and equipment on hand. This section lists methods, special equipment, and precautions necessary to control and clean up spills, leaks, and other releases. For example, if respirators are required to clean up a spill, that fact should be shown.
Acceptable waste-disposal methods, as well as prohibited methods, are described. The user will also be alerted to any potential environmental danger to the general population, crops, water supplies, etc.
Instructions for safe handling and storage, such as the warning not to store acids and bases together, may be given. Any additional special precautions not addressed elsewhere in the MSDS should also be listed here. These may include instructions for storage life or transportation, such as special packaging or temperature control.
Control Measures
This section is essential for protecting employees from overexposure. It lists personal protective equipment, such as proper gloves, safety glasses, or respirators, ventilation necessary to work safely with the material, and work/ hygienic practices. Types and descriptions of necessary equipment should be specified (e.g., organic vapor cartridge, neoprene gloves). If the material has a low TLV, indicating a dangerous health hazard, local ventilation is recommended, not general or dilution ventilation. Remember, engineering controls, such as the right kind of ventilation, are always preferable to relying on respirators.
Manufacturers may withhold certain information (such as specific chemical identities and/or amounts of its components) as proprietary on a Material Safety Data Sheet if the information is considered a trade secret. The Chemical Hygiene Officer has a legal right to obtain this information from the manufacturer to evaluate the potential health risk if potential overexposure or adverse health effects are suspected.
