Material Safety Data Sheets

July 1, 2002

Material Safety Data Sheets
An A&P's link to safety

By Paul A. Groves

As A&P technicians, our work environment poses special risks due to our exposure to paints, adhesives, solvents, cleaning agents, fuels, and lubricating oils. These materials are a part of our daily routine. Frequently, we may forget that these compounds, if not properly handled and used, can and do pose a threat to our health. Each state and the federal government require that all companies that manufacture or use hazardous materials must provide employees information and training on the proper handling and use of such materials. These rules are known as the "Right to Know" regulations.

The requirements for complying with the "Right to Know" rules were established in 1983, by OSHA. The "Right to Know" rules are officially known as the OSHA Hazard Communication Standard. This standard has five components. The first is that a company must maintain a list of all hazardous materials in the workplace. The second component is that Material Safety Data Sheets (MSDS) must be maintained for each hazardous material used in the workplace. The third is that all hazardous material containers must have labels that identify the material and provide visual and written warnings of the potential hazard to the employee. The fourth component requires that all employees be trained to identify and properly handle and use hazardous materials. The fifth component requires that a written program be developed and put in place to comply with this standard.

While all of the five components are important to protect the health and safety of you, the A&P, this article will focus on Material Safety Data Sheets. The MSDS is the cornerstone of the "Right to Know" rules and is your link to safety.

The MSDS contains from seven to 16 sections. While there is no specific format for an MSDS, the MSDS usually contains, in one form or another, the following information: (1) General Information, (2) Ingredients/Identity Information, (3) Physical/Chemical Characteristics, (4) Fire and Explosion Hazard Data, (5) Reactivity Data, (6) Health Hazard Data, (7) Precautions for Safe Handling and Use, (8) Control Measures, (9) Transportation Data, and (10) Disposal Data. The various entries may be further broken down to specific categories, such as first-aid measures, accidental release measures, regulatory requirements, and ecological information. In addition, the MSDS may also contain label data.

The following discussion of each section is directed toward what you, as an A&P, should know.

General information — This section contains the item or material’s name, the name and address of the manufacturer and most importantly, an emergency telephone number that is available 24 hours a day, seven days a week.

Ingredients/identity information — Information on specific compounds contained in the product are provided in this section. For example, Aviation Gasoline 100LL, contains no less than nine ingredients. The most important and relevant information is the PEL and the TLV. The PEL is the Personal/Permissible Exposure Limit. The TLV is the Threshold Limit Value. (See the attached glossary for an explanation of these and other terms in an MSDS.) Some of these values will have a STEL or Short Term Exposure Limit also listed. The bottom line for you as an A&P is that the lower the number the greater the risk. For example, the ingredient "Hexane" has a PEL of 500 ppm (parts per million) and a TLV of 50 ppm. While the ingredient "Benzene" has a PEL of 1 ppm, a STEL of 5 ppm, and a TLV of 10 ppm. In other words, Benzene is a greater risk to your health than Hexane.

Physical/chemical characteristics — One of the first items in this section describes the appearance and odor of the material. This section also contains the material’s boiling point, melting point, vapor density, and specific gravity. This information will tell you whether the material is a liquid, gas, or solid at normal room temperature.

For example, if the material is a vapor or gas, vapor density is important. Vapor density greater than 1.0 (the density of air) would tell you the gas will sink to the floor, if released. If the vapor or gas has a vapor density less than 1.0, it would rise.

The specific gravity of a liquid is important. A specific gravity less than 1.0 (the specific gravity of water) would tell you that the material would float on top of water. A specific gravity greater than 1.0, means water will float on top of the material.

Another data item to note is the material’s pH. The pH is a scale that ranges from 1 to 14 that is a measure of whether a material is acid (1 to 6) or caustic (base) (8 to 14). In other words sulfuric acid for a lead acid battery is acidic, Sodium hydroxide for a NiCad battery is caustic, and pure water is neutral (pH of 7.0). Protective gear needs to be worn when handling acidic or caustic materials.

Fire and explosion data — This section details the flash point, the lower and upper explosive limit and two items of special importance to you. The first of these is the type of extinguishing media to be used if the material catches fire. Putting water on some chemical fires will result in greater trouble and will be ineffective in putting out the fire. The second item is the requirement for special fire fighting procedures.

Reactivity — This section lists the relative stability of a material, its hazardous decomposition products, any hazardous polymerization, incompatible materials, and conditions to avoid.

Health hazard data – This area bears close attention by the A&P. This section lists the route of entry of the hazardous material into the human body. Special care and precautions must be taken, especially if the material is an inhalation hazard. The most rapid routes of entry for a hazardous material into the body are first, inhalation, second, absorption through the skin, and third, ingestion or swallowing. In addition, this section will provide you with medical conditions that will be aggravated by exposure to the material and most importantly, emergency first aid.

Precautions for safe handling and use — This section details steps to take if the material is spilled, if any neutralizing agents are needed, proper waste disposal methods, and precautions for handling and storage.

Control measures — This area contains information for respiratory protection, ventilation requirements in the work area; the type of protective gloves to be used when handling hazardous material, eye protection required, other protective equipment needed, and good work hygiene practices.

Transportation data — If this section is used, it will detail specific requirements for proper packaging and labeling of the material for shipment.

Disposal data — If this section is used, it will detail specific disposal requirements that entail special processing; disposal at a designated disposal facility; and local, state and federal regulations and requirements for notification of spills and disposal.

While the "Right to Know" rules require companies and management to inform and train you on hazardous materials in your workplace, the ultimate responsibility for your protection is you. Read applicable MSDS for your work area. Know how to access an MSDS quickly if an emergency does arise. Review MSDS on a regular basis. MSDS change over time. New formulations, updated health information, new technologies for storage, handling, and disposal are made on a continuing basis. The "Right to Know" rules are there to provide you, the A&P, with information, training, and protection when using hazardous materials. Be informed, be prepared, and think safety.

Paul Groves is the former owner and operator of a hazardous material remediation firm. He has instructed the Hazardous Waste Operations and Emergency Response (HAZWOPER) program for several firms. Groves is an A&P technician who has worked on FAR 121 heavy jets, corporate, and general aircraft and holds a Private Pilot’s License. Groves may be contacted via e-mail at fixandflypaul@ or (260) 373-2941 or (260) 348-1774.

Additional ReSources
Also use Keyword "MSDS" on AOL. It will provide over 100,000 sites.

MSDS GlossaryBoiling point — The temperature at which a liquid will change to a vapor, usually at standard atmospheric pressure.Carcinogen — A potential cancer causing agent in animals and humans.Flash point — The lowest temperature at which evaporation of a substance produces enough vapor to form an ignitable mixture with air.Explosive limit — The amount of vapor in the air that forms explosive mixtures; limits are expressed as upper and lower limits and give the range of vapor concentration in air that will explode if an ignition source is present.LD50/LC50 (Lethal dose/concentration 50) — The lethal dose/concentration of a compound where 50 percent of animals die from exposure. Melting point — The temperature at which a solid becomes a liquid at standard atmospheric pressure.PEL (personal/permissible exposure limit) — The upper limits/concentration of a compound allowed in the air of a workplace during an eight-hour workday.Specific gravity — A comparison of a compound’s weight per unit volume vs. a reference substance, usually water. Water is given a specific gravity of 1.0. Thus a compound that has a specific gravity less than 1.0 will float on water. A compound with a specific gravity greater than 1.0 will sink in water.STEL (short term exposure limit) — The maximum value/concentration of a compound that a worker is allowed to be exposed for a short period of time, usually 15 minutes. TLV (threshold limit value) — The airborne concentration of a compound in which nearly all workers may be exposed day after day without adverse effect.Vapor density — The density of a gas or vapor as compared to the density of air. Air has a vapor density of 1.0. If a gas or vapor has a vapor density greater than 1.0 it will sink to the floor, if released. If a gas or vapor has a vapor density less than 1.0, it will rise to the ceiling, if released.