MSDS and SDS have many terms and abbreviations.
ABSOLUTE: Chemical substance that is relatively free of impurities.
ABSOLUTE PRESSURE: The total pressure within a vessel, pipe, etc., not offset by external atmospheric pressure.
ABSORPTION: To take in and make a part of an existing whole. The penetration of a solid substance by a liquid as by capillary, osmotic, solvent or chemical action.
ACGIH: American Conference of Governmental Industrial Hygienists. An organization of professionals in governmental agencies or educational institutions engaged in occupational safety and health programs. ACGIH develops and publishes recommended occupational exposure limits for chemical substances and physical agents. (6500 Glenway Ave., Bldg. D-7, Cincinnati, OH. 45211;  661-7881.)
ACID: Any chemical which undergoes dissociation in water with the formation of hydrogen ions. Acids have a sour taste and may cause severe burns. They turn litmus paper red and have ph values of 0 to 6. Acids will neutralize bases or alkaline media. Acids will react with a base to form a salt.
ACIDOSIS: Condition of decreased alkalinity of the blood and tissues marked by sickly sweet breath, headache, nausea, vomiting, and visual disturbances; usually the result of excessive acid production.
ACRID: Irritating and bitter.
ACTION LEVEL: Exposure level at which OSHA regulations to protect employees takes effect. Exposure at or above the action level is termed occupational exposure. Exposure below this level can also be harmful.
ACTIVE INGREDIENT: Ingredient of a product that actually does what the product is designed to do. The remaining ingredients may be inert.
ACUTE EFFECT: Adverse effect on a human or animal body, that takes place soon after exposure.
ACUTE LETHALITY: Death of animals immediately or within 14 days after a single dose of or exposure to a toxic substance.
ACUTE TOXICITY: Adverse effects resulting from a single dose of or exposure to a substance.
ADSORB: Collect gas or liquid molecules on the surface of another material.
ADENOCARCINOMA: A tumor with glandular (secreting) elements.
ADENOSIS: Any disease of a gland.
ADHESION: A union of two surfaces that are normally separate.
AEROSOL: Fine aerial suspension of liquid (mist, fog) or solid (dust, fume, smoke) particles small enough to be stable.
AGENT: Any substance, force, radiation, organism, or influence that affects the body. Effects may be beneficial or injurious.
AIR-LINE RESPIRATOR: A respirator that is connected to a compressed breathable air source by a hose of small diameter. The air is delivered continuously or intermittently in a sufficient volume to meet the wearer's breathing requirements.
AIR-PURIFYING RESPIRATOR: A respirator that uses chemicals to remove specific gases and vapors from the air or that uses a mechanical filter to remove particulate matter. An air-purifying respirator must only be used when there is sufficient oxygen to sustain life and the air contaminant level is below the concentration limits of the device.
ALARA: Acronym for "as low as reasonably achievable."
ALKALI: Any chemical substance which forms soluble soaps with fatty acids. Alkalis are also referred to as bases. May cause severe burns to the skin. Alkalis turn litmus paper blue and have ph values from 8 to 14.
ALLERGIC REACTION: Abnormal physiological response to a chemical stimuli by a sensitive person.
ALLERGIC RESPIRATORY REACTION: Labored breathing, coughing, or gasping caused by inhaling a particular substance.
ALLERGIC SKIN REACTION: Reddening, swelling and/or itching of the skin following contact with a substance to which a person has become sensitized due to previous skin contact or natural body conditions.
ALOPECIA: Loss of hair.
AMBIENT: Usual or surrounding conditions.
AMENORRHEA: Absence of menstruation.
AMES TEST: Short term test commonly used for preliminary screening of chemicals to see if they cause mutations in a special type of bacterial cell.
ANALGESIA: Loss of sensitivity to pain.
ANESTHETIC: Chemical that causes a total or partial loss of sensation. Overexposure to anesthetics can cause impaired judgment, dizziness, drowsiness, headache, unconsciousness, and even death.
ANHYDRIDE: Compound derived from other compound by removing elements composing water (hydrogen and oxygen).
ANHYDROUS: No water. Substance in which no water molecules are present as hydrate or as water crystallization.
ANOREXIA: Loss of appetite.
ANOSMIA: Loss of the sense of smell.
ANOXIA: Lack of oxygen from inspired air.
ANSI: American National Standards Institute. A privately funded organization that identifies industrial/public national consensus standards and coordinates their development.
ANTIDOTE: Remedy to relieve, prevent, or counteract the effects of a poison.
ANURIA: Absence or defective excretion of urine.
API: American Petroleum Institute is an organization of the petroleum industry.
APNEA: Breathing temporarily stopped.
APPEARANCE: Physical state of a material.
AQUATIC TOXICITY (AQTX): Adverse effects on marine life that result from their being exposed to a toxic substance.
AQUEOUS: Water-based solution or suspension. Frequently, a gaseous compound dissolved in water.
ARGYRIA: Local or generalized gray/blue-colored impregnation of the body tissue with silver.
ARTICLE: Manufactured item specifically shaped or formed with function dependent on shape or design. Does not release or result in exposure to a hazardous material in normal use. Excluded from Hazard Communication Laws unless it gives off dust or fumes.
ASBESTOSIS: Chronic lung disease caused by inhaling airborne asbestos fibers.
ASPHYXIA: Lack of oxygen and interference with the oxygenation of the blood. Can lead to unconsciousness.
ASPHYXIANT: Vapor or gas which causes unconsciousness or death by suffocation. Most simple asphyxiants are harmful to the body only when they become so concentrated that they reduce oxygen in air (normally 21%) to dangerous levels (16% or lower). Asphyxiation is a potential hazard of working in confined spaces. Some examples of asphyxiants are Carbon Dioxide, Carbon Monoxide, Argon, etc. They function as asphyxiants by reducing the blood's ability to carry oxygen.
ASPIRATION HAZARD: Danger of drawing material into the lungs leading to an inflammatory response.
ASTHMA: Disease characterized by recurrent attacks of dyspnea, wheezing, and perhaps coughing caused by spasmodic contraction of the bronchiole in the lungs.
ASTM: American Society for Testing and Materials.
ASYMPTOMATIC: Neither causing nor exhibiting symptoms.
ATAXIA: Loss of muscular coordination.
ATMOSPHERE (atm.): Pressure measurement. One atmosphere (atm) = 14.7 lbs/sq in.
ATROPHY: Wasting or diminution in the size of tissue, organs, or the entire body caused by lack of use.
AUTOIGNITION TEMPERATURE: Minimum temperature which a substance must be heated without application of flame or spark to cause substance to ignite. Materials should not be heated to greater than 80% of this temperature.