Title: Unit 4 Glossary
Course: BLD 167 Hazardous Waste Operations and Emergency Response > Section: BLD 167 Hazardous Waste Operations and Emergency Response

Unit 4 Glossary

Terms

Term | Definitions
"Skin" | A notation (sometimes used with PEL or TLV exposure data) which indicates that the stated substance may be absorbed by the skin, mucous membranes, and eyes--either airborne or by direct contact--a ...
:g | Microgram, one-millionth of a gram.
Absorption | The process by which a substance can be readily taken into the body, for example, some chemicals can be absorbed through unbroken skin.
ACGIH | American Conference of Governmental Industrial Hygienists is an organization of professional personnel in governmental agencies or educational institutions that are employed in occupational safety ...
Acid | A fundamental category of chemicals characterized by having available reactive hydrogen and requiring an alkali to neutralize them.  Acids turn litmus paper red and have pH values of 0 to 6.  Th ...
Acute Effect | Adverse effect that has severe symptoms developing rapidly and coming quickly to a crisis.  Compare "Chronic Effect".
Adenocarcinoma | A tumor originating in a gland.
Adenosis | Any disease of a gland.
Adhesion | A union of two surfaces that are normally separate.
Aerosol | A fine spray of particles sufficiently small in size to resist settling or sedimentation (for example: smoke or fog).
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 whe ...
Airline Respirator | A respirator that is connected to a compressed breathing air source by a hose.  The air is delivered continuously or intermittently to a sufficient volume to meet the wearer's breathing requireme ...
Alkali | A substance capable of combining with hydrogen ions.  They are also called bases, and may cause severe burns to the skin.  Alkalis turn litmus paper blue and have pH values from 8 to 14.
Allergic Reaction | An abnormal physiological response to a chemical or physical stimuli by a sensitive person.
Alopecia | Loss of hair.
Amenorrhea | Absence of menstruation.
Analgesia | Loss of sensitivity to pain.
Anaphylaxis | Extreme sensitivity resulting from prior contact with a chemical or protein.
Anemia | A deficiency of red blood cells.
Anesthetic | A chemical that causes a total or partial loss of sensation.  Over exposure to anesthetics can cause impaired judgment, dizziness, drowsiness, headache, unconsciousness, and even death.  Example ...
Anhydride | An oxide or compound which when combined with water produces an acid or base.
Anhydrous | Does not contain water.
Anorexia | Loss of appetite.
Anosmia | Loss of the sense of smell.
Anoxia | A lack of oxygen from inhaled air - literally without oxygen.  See Hypoxia.
ANSI | American National Standards Institute is a privately funded, voluntary membership organization that identifies industrial and public needs for national consensus standards and coordinate developme ...
Antidote | A remedy to relive, prevent, or counteract the effects of a poison.
API | American Petroleum Institute is a voluntary membership organization of the petroleum industry.
Appearance | A description of a substance at normal room temperature and normal atmospheric conditions.  Appearance includes the color, size, and consistency of a material.
Aquatic Toxicity | The adverse effects to marine life that result from being exposed to a toxic substance.
Aqueous | A water-based solution.
Argyria | Local or generalized impregnation (gray-blue color) of the body tissues with silver.
Aromatic | Fragrant or of marked odor.  Often applied to a group of hydrocarbons and their derivatives, such as benzene, toluene, and xylene.
Asphyxia | Unconsciousness due to interference with the oxygen of the blood.
Asphyxiant | A vapor or gas that can cause unconsciousness or death by suffocation (lack of oxygen).  Most simple asphyxiants are harmful to the body only when they become so concentrated that they reduce oxy ...
Asphyxiation | A condition that causes asphyxia, suffocation.  See also Asphyxiant.
Asthma | A disease characterized by recurring attacks of difficulty breathing, wheezing, and coughs due to spasmodic contraction of the bronchioles.
ASTM | American Society for Testing and Materials is the world's largest source of voluntary consensus standards for materials, products, systems, and services.  ASTM is a resource for sampling and test ...
Asymptomatic | Showing no symptoms.
Ataxia | Loss of power of muscle coordination.
ATM | Atmosphere, a unit of pressure equal to 760 mmHg (mercury) at sea level.
Atmosphere Supplying Respirator | A respirator that provides breathing air from a source other than the surrounding atmosphere.  There are two types: air line and self-contained breathing apparatus.
Atrophy | A wasting or diminution in the size of the part of the body.
Auto-ignition Temperature | The temperature to which a closed or nearly closed container must be heated in order that the flammable liquid, when introduced into the container, will ignite spontaneously or burn.
BAL | British Anti-Lewisite - A name of the drug dimercaprol - a treatment for toxic inhalations.
Barrier Cream | A cream for use on human skin to protect against injury from contact with specific types of harmful agents.
Base | See Alkali.
BCM | Blood-clotting mechanism effects.
Benign | Not recurrent or not tending to progress.
Biodegradable | Capable of being broken down into innocuous products by the action of living things.
Biohazard | This is a combination of the words biological and hazard; and is used to describe infectious agents presenting a risk or potential risk to the well-being of man or animals either directly through ...
Biologic half-life | The time required for a given species, organ, or tissue to eliminate half of a substance which it takes in.
Biopsy | Removal and examination of tissue from the living body.
BLD | Blood effects.
Boiling Point | The temperature at which a liquid changes to vapor state at a given pressure.  The boiling point is usually expressed in degrees Fahrenheit at sea level pressure (760 mmHg, or one atmosphere).  ...
Bonding | The interconnecting of two objects by means of a clamp and bare wire.  Its purpose is to prevent a static discharge (spark) when transferring a flammable liquid from one container to another.  T ...
Bradycardia | A slow heartbeat in which the pulse rate falls below 60.  See also Tachycardia.
Breathing Zone | The area of the ambient environment in which a person breathes.
Bronchitis | Inflammation of the bronchial tubes in the lungs.
Buffer | A substance capable in solution of neutralizing both acids and bases and thereby maintaining the original acidity of basicity of the solution.
Bulk Density | Mass of powdered or granulated solid material per unit of volume.
C | Degree Centigrade, a temperature scale where water boils at 100 degree C and freezes at 0 degrees C.  Degrees C = 5/9 (degrees F -32).
ca | Approximately.
CAA | Clean Air Act was enacted by Congress to regulate/reduce air pollution.  CAA is administered by the Environmental Protection Agency.
Car | Cancer or carcinogen.
Carcinogen | A substance or agent capable of causing or producing cancer in mammals, including humans.  A chemical is considered to be a carcinogen if:             (a)        It has bee ...
Carcinogenicity | A malignant tumor.  A form of cancer.
CAS | Chemical Abstracts Service is an organization under the American Chemical Society.  CAS abstracts and indexes chemical literature from all over the world in "Chemical Abstracts."  "CAS Numbers" ...
Catalyst | A substance which, without changing itself, causes a chemical reaction to proceed faster.
Cataract | A loss of transparency of the crystalline lens of the eye or of it capsule.
Caustic | The ability of an alkali to cause burns.  See Alkali.
CBRN | Chemical, Biological, Radiological and Nuclear. Also an approval for Respirators by NIOSH for use of particular Respirators after or during terrorist attacks.
cc | Cubic centimeter is a volume measurement in the metric system which is equal in capacity to one milliliter (ml).  One quart is about 946 cubic centimeters.
Ceiling (TLV-C) | The concentration that should not be exceeded even momentarily.
Ceiling Limit | A concentration that is not to be exceeded.  See also "C" or Ceiling.
Ceiling Value(s) | A maximum established level which no human exposure should ever exceed.
Central Nervous System | The brain and spinal cord.  These organs supervise and coordinate the activity of the entire nervous system.  Sensory impulses are transmitted into the central nervous system, and motor impulses ...
CERCLA | Comprehensive Environmental Response Compensation, and Liability Act of 1980.  The act requires that the Coast Guard National Response Center be notified in the event of a hazardous substance rel ...
Cervix | The lower end of the uterus extending into the vagina.
CFR | Code of Federal Regulations.  A collection of the regulations that have been promulgated under U.S. Law.
Chemical | Any element, chemical compound, or mixture of elements and/or compounds where chemical(s) are distributed.
Chemical Cartridge Respirator | A respirator that uses various chemical substances to purify inhaled air of certain gases and vapors.  This type of respirator is effective for concentrations no more than ten times the TLV of th ...
Chemical Change (Reaction) | Change of composition in properties due to rearrangement of elements, atoms, or molecules.
Chemical Compound | A substance composed of definite proportions by weight of two or more elements, and whose properties differ from those of its elements.  Also, see Mixture.
Chemical Family | A group of individual elements or compounds with a common general name.  Example:  Ketones, Alcohols.
Chemical Name | The name given to a chemical in the nomenclature system developed by the International Union of Pure and Applied Chemistry (IUPAC) or the Chemical Abstracts (CAS).
Chemical Pneumonitis | Inflammation of the lungs caused by accumulation of fluids due to chemical irritation.
Chemtrec | Chemical Transportation Emergency Center is a national center established by the Chemical Manufacturers Association (CMA) to relay pertinent emergency information concerning specific chemicals on ...
Chloracne | acne like eruption from contact with chlorinated naphthalenes and polyphenyls acting on sweat glands.
Chronic Effect | An adverse effect on a human or animal body, with symptoms which develop slowly over a long period of time or which recur frequently.  Compared with Acute it has the opposite meaning.
Chronic Exposure | Long-term contact with a substance.
Chronic Toxicity | Adverse effects resulting from repeated doses of or exposures to a substance over a relatively prolonged period of time.  Ordinarily used to denote effects in experimental animals.
Clean Air Act | See CAA.
Clean Water Act | Federal law enacted to regulate/reduce water pollution.  The Environmental Protection Agency administers CWA.
CMA | Chemical Manufacturers Association.  See CHEMTREC.
CO | Carbon monoxide.  A colorless, odorless, flammable, and very toxic gas produced by the incomplete combustion of carbon.  It is also a by-product of many chemical processes.
CO2 | will not burn and is relatively non-toxic (although high concentrations, especially in confined spaces, can create hazardous oxygen deficient environments).
COC | Cleveland Open Cup is a flash point test method.
Combustible | A term used by NFPA, DOT, and others to classify certain liquids that will burn, based on flash points.  Both NFPA and DOT generally define "combustible liquids" as having a flash point of 100 de ...
Combustible Liquid | Any liquid having a flashpoint at or above 100 degrees F (37.8 degrees C), but below 200 degrees F (93.3 degrees C), except any mixture having components with flashpoints of 200 degrees F (93.3 de ...
Common Name | Any identification, such as code name, code number, trade name, brand name, or generic name, other than its chemical name, used to identify a chemical.
Compressed Gas | (a) A gas or mixture of gases having, in a container, an absolute pressure exceeding 40 psi at 70 degrees F (21.1 C degrees); or (b) A gas or mixture of gases having, in a container, an absolute p ...
Conc. | See "Concentration."
Concentration | The relative amount of a substance when combined or mixed with other substances.  Examples:  2-ppm hydrogen sulfide in air, or a 50 percent caustic solution.
Conditions to Avoid | Conditions encountered during handling or storage that could cause a substance to become unstable.
Confined Space | Any area which has limited openings for entry and exit that would make escape difficult in an emergency, has a lack of ventilation, contains known and potential hazards, and is not intended nor de ...
Conjunctivitis | Inflammation of the conjunctiva, the delicate membrane that lines the eyelids and covers the eyeballs.
Contact Dermatitis | Caused by contact with a primary irritant, a skin irritant at the area of skin contact.
Container | Any bag, barrel, bottle, box, can, cylinder, drum, reaction vessel, storage tank, or the like that contains a hazardous chemical.  For purposes of MSDS or HazCom, pipes or piping systems are not ...
Cornea | Transparent structure of the external layer of the eyeball.
Corrosive | A chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact.  This term shall not refer to action on inanimate surfaces.
CPSC | Consumer Products Safety Commission has responsibility for regulating hazardous materials when they appear in consumer goods.  For CPSC purposes, hazards are defined in the Hazardous Substances A ...
Cryogen | A substance that is cooled to a very low temperature keeping it in liquid state typically boils at < -160°C.
Cultaneous Hazards | Chemicals, which irritate the skin.
Cultaneous hazards | Chemicals, which affect the dermal layer of the body.
Cultaneous Toxicity | See Dermal Toxicity.
Curettage | Cleaning of diseased surface.
CWA | Clean Water Act was enacted to regulate / reduce water pollution.  It is administered by EPA.
Cyanosis | Blueness of the skin, generally caused by lack of oxygen.
Cyst | A sac containing a liquid.  Most cysts are harmless.
Cytology | The scientific study of cells.
DASHO | Designated Agency Safety and Health Official is the executive official of a Federal Department or Agency who is responsible for safety and occupational health matters within a Federal agency, and ...
Decomposition | Breakdown of a material or substance (by heat, chemical reaction, electrolysis, decay, or other process) into parts or elements or simpler compounds.
Density | The mass (weight) per unit volume of a substance.  For example, lead is much more dense than aluminum.
Depressant | A substance that reduces a bodily functional activity or an instinctive desire, such as appetite.
Dermal | Relating to the skin.
Dermal Toxicity | Adverse effects resulting from skin exposure to a substance.  Ordinarily used to denote effects in experimental animals.
Dermatitis | Inflammation of the skin.  Also, see Irritant, Sensitized, and Contact Dermatitis.
DHHS | U.S. Department of Health and Human Services (replaced U.S. Department of Health, Education, and Welfare).  NIOSH and the Public Health Service (PHS) are part of DHHS.
Dike | A barrier constructed to control or confines hazardous substances and prevents them from entering sewers, ditches, streams, or other flowing waters.
Dilution Ventilation | Airflow designed to dilute contaminants to acceptable levels.  Also, see General Ventilation of Exhaust.
DOL | U.S. Department of Labor.  OSHA and MSHA are part of DOL.
Dose | The term used to express the amount of energy or substance absorbed in a unit volume of an organ or individual dose rate is the dose delivered per unit of time.
DOT | U.S. Department of Transportation regulates transportation of chemicals and other substances.
Dry Chemical | A powdered fire-extinguishing agent usually composed of sodium bicarbonate, potassium bicarbonate, etc...
Dysfunction | Any abnormality or impairment of an organ.
Dysmenorrhea | Painful menstruation.
Dysplasia | An abnormality of development.
Dyspnea | Labored or difficult breathing, shortness of breath.
Ectopic Pregnancy | The fertilized ovum becomes implanted outside of the uterus.
Eczema | A skin disease or disorder; one specific type of dermatitis.
Edema | An abnormal accumulation of clear watery fluid in the tissues.
Element | A substance composed entirely of one kind of atom.  Elements are designated by chemical symbols.
Emphysema | A lung disease in which the presence of air in the connective tissues of the lungs causes swelling or inflammation.
Endocrine Glands | Glands that regulate body activity by secreting hormones.
Endometrium | The mucous membrane lining the uterus.
Environmental Toxicity | Information obtained because of conducting environmental testing designed to study the effects on aquatic and plant life.
EPA | U.S. Environmental Protection Agency.
Epidemiology | Science concerned with the study of disease in general population.  Determination of the incidence (rate of occurrence) and distribution of a particular disease (as by age, sex, or occupation), w ...
Epistaxis | Nosebleed, hemorrhage from the nose.
Epithelium | The thin membrane covering internal and external surfaces of the body.
Estrogen | Principal female sex hormone.
Evaporation Rate | The rate at which a material will vaporize (evaporate) when compared to the known rate of vaporization of a standard material.  The evaporation rate can be useful in evaluating the health and fir ...
Explosive | A chemical that causes a sudden, almost instantaneous release of pressure, gas, and heat when subjected to sudden shock, pressure, or high temperature.
Exposure or Exposed | State of being open and vulnerable to a hazardous chemical in the course of employment by inhalation, ingestion, and skin contact, absorption, or any other course; includes potential (accidental o ...
Extinguishing Media | The firefighting substance to be used to control a material in the event of a fire.  It is usually named by its generic name, such as fog, foam, water, etc...
Eye hazards | Chemicals that affect the eye or visual capacity.
Eye Protection | Recommended safety glasses, chemical splash goggles, face shields, etc., to be utilized when handling a hazardous material.
F | Fahrenheit is a scale for measuring temperature.  On the Fahrenheit scale, water boils at 212 degrees and freezes at 32 degrees, F = 9/5 (degrees C) + 32.
f/cc | Fibers per cubic centimeter of air.
FACOSH | Federal Advisory Council for Occupational Safety and Health is a joint management-labor council that advises the Secretary of Labor on matters relating to the occupational safety and health of fed ...
FDA | U.S. Food and Drug Administration.
Fetal | Pertaining to the fetus.
Fetus | The developing young in the uterus from the seventh week of gestation until birth.
FFSHC | Field Federal Safety and Health Councils are organized throughout the country to improve federal safety and health programs at the field level and within a geographic location.
FHCP | Federal Hazard Communication Program.
Fibrosis | An abnormal thickening of fibrous connective tissue, usually in the lungs.
FIFRA | Federal Insecticide, Fungicide, and Rodenticide Act requires that certain useful poisons, such as chemical pesticides, sold to the public contain labels that carry health hazard warnings to protec ...
First Aid | Emergency measures to be taken when a person is suffering from overexposure to a hazardous material, before regular medical help can be obtained.
Flammable | A chemical that includes one of the following categories:             (a)        "Aerosol, Flammable."  An aerosol that yields a flame projection exceeding 18 inches at full ...
Flashback | Occurs when flame from a torch burns back into the tip, the torch, or the hose.  It is often accompanied by a hissing or squealing sound with a smoky or sharp-pointed flame.
Flashpoint | The minimum temperature at which a liquid gives off a vapor in sufficient concentration to ignite when tested by the following methods:             (a)        Tagliabue Close ...
Foreseeable Emergency | Any potential occurrence such as, but not limited to, equipment failure, rupture of containers, or failure of control equipment, which could result in an uncontrolled release of a hazardous chemic ...
Formula | The scientific expression of the chemical composition of a material (e.g., water is H_2O, sulfuric acid is H_2SO_4, sulfur dioxide is SO_2).
Fume | Smoke, vapor, or gas, especially when irritating or offensive.
Fume Fever | An acute condition caused by a brief high exposure to the freshly generated fumes of metal such as lead or magnesium.
g | Gram is a metric unit of weight.  One ounce U.S. (avoirdupois) is about 28.4 grams.
g/kg | Grams per kilogram is an expression of dose used in oral and dermal toxicology testing to denote grams of a substance dosed per kilogram of animal body weight.  Also, see kg (kilogram).
Gangrene | Death of tissue combined with putrefaction.
Gastroenteritis | Inflammation of the stomach and intestines.
General Exhaust | A system for exhausting air-containing contaminants from a general work area.  Also, see Local Exhaust.
Generic Name | A designation or identification used to identify a chemical by other than its chemical name (e.g., code name, code number, trade name, and brand name).
Genetic | Pertaining to or carried by genes.  Hereditary.
Gestation | The development of the fetus from conception to birth.
Grounding | The procedure used to carry an electrical charge to ground through a conductive path.  A typical ground may be connected directly to a conductive water pipe or to a grounding bus and ground rod.
Gynecology | The study of the reproductive organs in women.
Hand Protection | Specific type of gloves or other hand protection required to prevent harmful exposure to hazardous materials.
Hazard Warning | Words, pictures, symbols, or combination thereof presented on a label or other appropriate form to inform of the presence of various materials or hazards.
Hazardous chemical | Any chemical whose presence or use is a physical hazard or a health hazard.
Hazardous Chemical | Any chemical whose presence or use is a physical hazard or a health hazard.
Hazardous Material | A material that is characterized by one or more of the following (1) has a flashpoint below 140 degrees, closed cup, or subject to spontaneous heating; (2) has a threshold limit value below 500 pp ...
HCS | Hazard Communication Standard is an OSHA regulation.
Health Hazard | A chemical for which there is significant evidence, based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur in exp ...
Hematology | The study of blood.
Hematoma | A blood clot under the surface of the skin.
Hematopoietic System | The blood forming mechanism of the human body.
Hematuria | The presence of blood in the urine.
Hemoglobin | An iron-containing conjugated protein or respiratory pigment occurring in the red blood cells of vertebrates.
Hepatotoxin | A substance that causes injury to the liver.
Hepatoxins | Chemicals that produce liver damage.
Highly Toxic | A chemical falling within any of the following categories:             (a)        A chemical with a median lethal dose (LD50) of 50 milligrams or less per kilogram of body w ...
HMIS | Hazardous Material Information System is an MSDS file maintained by the Department of Defense and contains MSDSs and transportation data for products purchased by DOD and GSA.
Hormones | Act as chemical messengers to body organs.
Hydrocarbons | Chemicals composed solely of carbon and hydrogen, which are the basic building blocks of all organic chemicals.
Hygroscopic | Readily absorbs moisture from the air.
Hyperplasia | Increase in volume of a tissue or organ caused by the growth of new cells.
Hypoxia | Insufficient oxygen, especially as applied to body cells.
IARC | International Agency for Research on Cancer.
Ignitable | Capable of being set afire.
Immiscible | Liquids that will not mix with each other but will form 2 separate layers or will result in cloudiness or turbidity.
Impervious | A material that does not allow another substance to pass through or penetrate it.
Incompatible | Materials that could cause dangerous reactions by direct contact with one another are described as incompatible.
Inflammation | A morbid series of reactions produced in the tissues by an irritant.  It is marked by an afflux of blood with exudation of plasma and leukocytes.
Ingestion | Taking in by the mouth.
Inhalation | Breathing in of a substance in the form of a gas, vapor, fume, mist, or dust.
Inhale | See Inhalation.
Inhibitor | A chemical added to another substance to prevent an unwanted chemical change.
Inorganic | A term used to designate compounds that generally do not contain carbon.  Source matter other than vegetable or animal.  Examples are sulfuric acid and salt.
Insol | See Insoluble.
Insoluble | Incapable of being dissolved in a liquid.
Intrauterine | Within the uterus.
Iridocyclitis | Inflammation of both iris and ciliary body of the eye.
Irritant | A chemical, which is not corrosive, but which causes a reversible inflammatory effect on living tissue by chemical action at the site of contact.
Irritating | An irritating material, as defined by DOT, is a liquid or solid substance which, upon contact with fire or when exposed to air, gives off dangerous or intensely irritating fumes (not including poi ...
Ischemia | Local and temporary anemia due to the obstruction of the circulation in a part of the body.
kg | Kilogram is a metric unit of weight, about 2.2 U.S. pounds.  Also, see g/kg, g and mg.
L | Liter is a metric unit of capacity or volume.  A U.S. quart is about 9/10 of a liter.
Label | Notice attached to a container, bearing information concerning its contents.
Lacrimation | Secretion and discharge of tears.
Lactation | The secretion of milk by the breasts.
Latent Period | The period of time between exposure and the first manifestation of damage.
Lavage | A washing of a hollow organ, such as the stomach.
LC | Lethal Concentration is the concentration of a substance being tested that will kill.
LC50 | The concentration of a material in air that will kill 50 percent of a group of test animals with a single exposure (usually 1 to 4 hours).  The LC50 is expressed as part of material per million p ...
LCL | Lethal Concentration Low, lowest concentration of a gas or vapor capable of killing a specified species, over a specified time.
LD | Lethal Dose is the quantity of a substance being tested that will kill.
LD50 | A single dose of material expected to kill 50 percent of a group of test animals.  The LD dose is usually expressed as milligrams or grams of material per kilogram of animal body weight (mg/kg or ...
LDL | Lethal Dose Low, lowest administered dose of material capable of killing a specified test species.
Lead Intoxication | Lead absorption resulting from inhalation of lead dust or fumes, or from swallowing lead dust.
LEL, or LFL | Lower Explosive Limit, or Lower Flammable Limit, of a vapor or gas; the lowest concentration (lowest percentage of the substance in the air) that will produce a flash of fire when an ignition sour ...
Lesion | Any damage to a tissue.
Lethal Concentration - LC | A concentration of a substance that is sufficient to kill a test animal.
Lethal Concentration 50 - LC50 | See LC50.
Lethal Dose 50 -LD50 | See LD 50.
Lethal Dose LD | An amount of a substance that is sufficient to kill a test animal.
Leukemia | A disease of the blood marked by persistent increase in white blood cells, associated with changes in the spleen, the bone marrow, or the lymphatic modes.
LFM | Linear feet per minute, a unit of air velocity.
Local Exhaust | A system for capturing and exhausting contaminants from the air at the point where the contaminants are produced (welding, grinding, sanding, other processes, or operations).  Also, see General E ...
M | Meter is a unit of length in the metric system.  One meter is about 39 inches.
m | Cubic meter is a metric measure of volume, approximately 35.3 cubic feet or 1.3 cubic yards.
Malaise | A feeling of general discomfort, distress, or uneasiness, an "out-of-sorts" feeling.
Malignant | Tending to become progressively worse and to result in death, often used in describing tumors.
Mammary | Pertaining to the breast.
Mechanical Exhaust | A powered device, such as a motor-driven fan, or stream Venturi tube, for removing contaminants from a workplace, vessel, or enclosure.
Mechanical Filter Respirator | A respirator used to protect against airborne particulate matter like dusts, mists, metal fumes, and smoke.  Mechanical filter respirators do not provide protection against gases, vapors, or oxyg ...
Melting Point | The temperature at which a solid substance changes to a liquid state.
Menorrhagia | Excessive menstruation.
Menstruation | Periodic discharge of blood from the vagina from a non-pregnant uterus.
MESA | Mining Enforcement and Safety Administration.
Metabolism | The physical and chemical processes by which living organisms produce the necessary energy to maintain life.
Metastases | The transfer of disease form one organ or part to another not directly connected with it.
Meter | A unit of length, equivalent to 39.37 inches.
mg | Milligram is a metric unit of weight, which is one thousandth of a gram.
mg/kg | Milligrams of substance per kilogram of body weight is an expression of toxicological dose.
mg/m | Milligrams per cubic meter is a unit for expressing concentration of dusts, gases, or mists in air.
Micron | Micron is a unit of length equal to one millionth of a meter.  A micron is approximately 1/23,000 of an inch.
Mid | Mild.
Mist | Suspended liquid droplets generated by condensation from the gaseous to the liquid state, or by breaking up a liquid into a dispersed state, such as splashing, foaming or atomizing.  Mist is form ...
Mixture | Any combination of two or more chemicals if the combination is not, in whole or part, the result of a chemical reaction.
ml | Milliliter is a metric unit of capacity, equal in volume to one cubic centimeter (cc), or approximately 1/16 of a cubic inch.  One thousandth of a liter.
Mld | Mild.
mmHg | Millimeters (mm) of mercury (Hg) is a unit of measurement for low pressures of partial vacuums.
Molecular Weight | Weight (mass) of a molecule based on the sum of the atomic weights of the atoms that make up the molecule.
mppcf | Million particles per cubic foot is a unit for expressing concentration of particles of a substance suspended in air.  Exposure limits for mineral dusts (silica, graphite, Portland cement, nuisan ...
MSDS | Material Safety Data Sheet.
MSHA | Mine Safety and Health Administration, U.S. Department of Labor.
Mutagen | A substance or agent capable of altering the genetic material in a living cell.
MW | See Molecular Weight.
N | Nitrogen is a colorless, odorless, and tasteless gas that will not burn and will not support combustion.  The earth's atmosphere (air) is about 78 percent nitrogen.  At higher concentrations, ni ...
Narcosis | A state of stupor, unconsciousness, or arrested activity produced by the influence of narcotics or other chemicals.
Nausea | Tendency to vomit, feeling of sickness at the stomach.
NCI | National Cancer Institute is that part of the National Institute of Health which studies cancer causes and prevention as well as diagnosis, treatment, and rehabilitation of cancer patients.
Necrosis | Local death of tissue.
Neo | See Neoplasia.
Neonatal | The first 4 weeks after birth.
Neoplasia | A condition characterized by the presence of new growths (tumors).
Nephrotoxin | A material that affects the nerve cells and may produce emotional or behavioral abnormalities.
Nephrotoxins | Chemicals that produce kidney damage.
Neurotoxins | Chemicals that produce their primary toxic effects on the nervous system.
Neutralize | To eliminate potential hazards by inactivating strong acids, caustics, and oxidizers.  For example, acids can be neutralized by adding and appropriate amount of caustic substance (alkali or base) ...
NFPA | National Fire Protection Association is an international membership organization which promotes/improves fire protection and prevention, and establishes safeguards against loss of life and propert ...
ng | Nanogram, one-billionth of a gram.
NIOSH | National Institute for Occupational Safety and Health, U.S. Public Health Service, U.S. Department of Health and Human Services (DHHS), among other activities, tests and certifies respiratory prot ...
Non-Sparking Tools | Tools made from beryllium-copper or aluminum-bronze greatly reduce the possibility of igniting dusts, gases, or flammable vapors.  Although these tools may emit some sparks when striking metal, t ...
Nonflammable | Not easily ignited, or if ignited, not burning rapidly.
NOx | Oxides of nitrogen, which are undesirable air pollutants.  NOx emissions are regulated by EPA under the Clean Air act.
NPIRS | National Pesticide Information Retrieval System is an automated database operated by Purdue University containing information on EPA registered pesticides, including reference file MSDSs.
NRC | National Response Center is a notification center, which must be called when significant oil or chemical spills or other environment-related accidents occur.  The toll-free telephone number is 1- ...
NTP | National Toxicology Program.  The NTP publishes an Annual Report on Carcinogens.
Nystagmus | Either spasmic, involuntary motion of the eyeballs, in a horizontal, vertical or a circular pattern.
Odor | A description of the smell of the substance.
Odor Threshold | The lowest concentration of a substance's vapor, in air, that can be smelled.
OFAP | Office of Federal Agency Programs is the organization unit of OSHA, which provides federal agencies with guidance to develop and implement occupational safety and health programs for federal emplo ...
Olfactory | Relating to the sense of smell.
Olfactory Fatigue | Relating to loss of sense of smell after exposure.  Hydrogen Sulfide (H2S) has this affect shortly after exposure and is toxic.
Oliguria | Scanty or low volume of urine.
Oral | Used in or taken into the body through the mouth.
Oral Toxicity | Adverse effects resulting from taking a substance into the body by mouth.  Ordinarily used to denote effects in experimental animals.
Organic Peroxide | An organic compound that may be considered a structural derivative of hydrogen peroxide.
Organogenesis | The secretion of tissues into different organs in embryonic development.
OSHA | Occupational Safety and Health Administration.  U.S. Department of Labor.  Williams and Stieger Act of 1970.
Ovary | The female sex gland in which ova (eggs) are formed.
Overexposure | Exposure to a hazardous material beyond the allowable exposure levels.
Ovulation | The process in which an ovum (egg) is discharged from an ovary.
Ovum | Egg.
Oxidation | A reaction in which a substance combines with oxygen.
Oxidation-Reduction Reaction | A chemical reaction in which an atom or molecule loses electrons to another atom or molecule.
Oxidizer | A chemical other than a blasting agent or explosive that initiates or promotes combustion in other materials, causing fire either by itself for through the release of oxygen or other gases.
Oxidizing Agent | A chemical or substance that brings about an oxidation reaction.
Papanicolaou Smear (Pap Smear) | Test most commonly used to detect cancer of the uterus and cervix.
Pathologic | Pertaining to or caused by disease.
Pathology | Scientific study of alterations produced by disease.
PEL | Permissible Exposure Limit is an exposure limit established by OSHA's regulatory authority.  It may be a time weighted average (TWA) limit or a maximum concentration exposure limit.  See also TL ...
Percent Volatile | Percent volatile by volume is the percentage of a liquid or solid (by volume) that will evaporate at an ambient temperature of 70 degrees F (unless some other temperature is specified).  Examples ...
Personal Protective Equipment - PPE | Devices worn by the worker to protect against hazards in the environment.  Respirators, gloves, chemical resistant PPE, and ear protectors are examples.
pH | The symbol relating the hydrogen ion (H-) concentration to that of a given standard solution.  A pH of 7 is neutral.  Numbers increasing from 7 to 14 indicate greater alkalinity.  Numbers decre ...
Physical Hazard | A chemical for which there is scientifically valid evidence that it is a combustible liquid, a compressed gas, explosive, flammable, an organic peroxide, an oxidizer, pyrophoric, unstable (reactiv ...
Placenta | A structure that grows on the wall of the uterus during pregnancy, through which the fetus is nourished.
PMCC | Pensky-Martens Closed Cup.  See Flash Point.
Pneumoconiosis | A condition of the lung in which there is permanent deposition of particulate matter and the tissue reaction to its presence.  It may range from relatively harmless forms of iron oxide deposition ...
Poison, Class A | A DOT term for extremely dangerous poisons--poisonous gases or liquids that, in very small amounts either as gas or as vapor of the liquid, mixed with air, are dangerous to life.  Examples:  pho ...
Poison, Class B | A DOT term for liquid, solid, paste or semisolid substances--other than Class A poisons or irritating materials--that are known (or presumed on the basis of animal tests) to be so toxic to humans ...
Polymerization | A chemical reaction in which one or more small molecules combine to form larger molecules.  A hazardous polymerization is a reaction that takes place at such a rate that large amounts of energy a ...
ppb | Parts per billion is the concentration of a gas or vapor in air--parts (by volume) of the gas or vapor in a billion parts of air.  Usually used to express extremely low concentrations of unusuall ...
ppm | Parts per million is the concentration of a gas or vapor in air--parts(by volume ) of the gas or vapor in a million parts of air; also the concentration of a particular substance in a liquid or so ...
Prenatal | Preceding birth.
psi | Pounds per square inch (for MSDS purposes) is the pressure a material exerts on the walls of a confining vessel or enclosure.  For technical accuracy, pressure must be expressed as psig (pounds p ...
Pul | See Pulmonary.
Pulmonary | Relating to, or associated with, the lungs.
Pulmonary Agent | Chemicals that may damage the lungs.
Pulmonary Edema | Fluid in the lungs.
Pyrophoric | A chemical that will ignite spontaneously in air at a temperature of 130 degrees F (54.4 degrees C) or below.
RCRA | Resource Conservation and Recovery Act is environmental legislation aimed at controlling the generation, treating, storage, transportation, and disposal of hazardous waste.  It is administered by ...
Reaction | A chemical transformation or change.  The interaction of two or more substances to form new substances.
Reactive | See unstable.
Reactivity | Chemical reaction with the release of energy.  Undesirable effects--such as pressure buildup, temperature increase, and formation of noxious, toxic, or corrosive by-products-may occur because of ...
Reducing Agent | In a reduction reaction ( which always occurs simultaneously with an oxidation reaction) the reducing agent is the chemical or substance, which (1) combines with oxygen or (2) loses electrons to t ...
REL | The NIOSH REL (Recommended Exposure Limit) is the highest allowable airborne concentration, which is not expected to injure the workers.  It may be expressed as a ceiling limit or as a time-weigh ...
Reproductive Toxin | Chemicals, which have a negative effect on the reproductive capabilities, including chromosomal damage (mutations) and birth defects to the fetus (teratogenesis).
Reproductive toxins | Chemicals that affect the reproductive capabilities including chromosomal damage (mutations) and effects on fetuses (teratogenesis).
Respirator | A device designed to protect the wearer from the inhalation of contaminated air.
Respiratory Disease | Any disease, which affects the lungs or the respiratory tract.
Respiratory Irritants | Any chemical that produces a reversible inflammatory effect on the respiratory system.
Respiratory Protection | Devices that will protect the wearer's respiratory system from overexposure by inhalation of airborne contaminants.  Respiratory protection is sued when a worker must work in an area where he/she ...
Respiratory System | The breathing system that includes the lungs and the air passages (trachea or "windpipe," larynx, mouth, and nose) to the air outside the body, plus the associated nervous and circulatory supply.
Routes of Entry | An OSHA-approved closed container which has the following characteristics:  (1)  a capacity of not more than 5 gallons (19 liters);  (2) a spring-closing lid and spout cover; (3) flash-arrestin ...
Sarcoma | A malignant tumor arising in connective tissues such as bone or cartilage.
Saturation | The maximum concentration of matter that can be dissolved in a solution at a given temperature.
Self-Contained Breathing Apparatus | A respiratory protection device that consists of a supply or a means of respirable Grade D air, oxygen, or oxygen generating material, carried by the wearer.
Sensitizer | A chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical.
SETA | Setaflash Closed Tester.  See Flash Point.
Short-Term-Exposure Limit (TLV-STEL) | This is the maximum concentration to which workers can be exposed for a period up to 15 minutes continuously without suffering from (1) irritation, (2) chronic or irreversible tissue change, or (3 ...
Silicosis | A disease of the lungs caused by the inhalation of silica dust.
Skin | Skin.
Skin Absorption | Ability of some hazardous chemicals to pass directly through the skin and enter the bloodstream.
Skin Sensitizer | See sensitizer.
Skin Toxicity | See Dermal Toxicity.
Soln | Solution
Solubility in Water | A term expressing the percentage of a material (by weight) that will dissolve in water at ambient temperature.  Solubility information can be useful in determining spill clean-up methods and re-e ...
Solvent | A substance, usually a liquid, in which other substances are dissolved.  The most common solvent is water.
SOx | Oxides of sulfur.
SOx | Oxides of Sulfur.
Species | On the MSDSs, species refers to the test animals--usually rats, mice, or rabbits--used to obtain the toxicity test data reported.
Specific Chemical Identity | The chemical name, Chemical Abstracts Service (CAS) Registry Number, or any precise chemical designation of a substance.
Specific Gravity | The weight of a material compared to the weight of an equal volume of water is an expression of the density (or heaviness) of a material, insoluble materials with specific gravity of less that 1.0 ...
Spill or Leak Procedures | The methods, equipment, and precautions that are designed to clean up or contain substances that have spilled or leaked.
Splash Proof Goggles | Eye protection made of a non-corrosive material that fits snugly against the face, and has indirect ventilation ports.
Spontaneously Combustible | A material that ignites as a result of retaining heat from processing, or which will oxidize to generate heat and ignite, or which absorbs moisture to generate heat and ignite.
Squamous | Scaly or platelike.
Stability | The ability of a material to remain unchanged.  For MSDS purposes, a material is stable if it remains in the same form under expected and reasonable conditions of storage or use.  Conditions whi ...
STEL | Short Term Exposure Limit (ACGIH terminology).  See also TLV.
Stenosis | A complex molecule among which are the male and female sex hormones.
Stupor | Partial or nearly complete unconsciousness.
Subcutaneous | Beneath the layers of the skin.
Supplied Air Respirators | Airline respirators of self-contained breathing apparatus.
Synonym | Another name or names by which a material is known.  Methyl alcohol, for example, is also known as methanol or wood alcohol.
Sys | System or systemic.
Systemic Poison | A poison, which spreads throughout the body, affecting all body systems and organs.  Its adverse effect is not localized in one spot or area.
Systemic Toxicity | Adverse effects caused by a substance, which affects the body in a general rather than local manner.
Tachycardia | Excessively rapid heartbeat.  See also Bradycardia.
Target organ effects | The following is a target organ categorization of effects, which may occur, including examples of signs and symptoms and chemicals, which have been found to cause such effects.  These examples ar ...
Target Organ Toxin | A toxic substance that attacks a specific organ of the body.  For example, overexposure to carbon tetrachloride can cause liver damage.
TCC | Tag (Tagliabue) Closed Cup.  See Flash Point.
TCL | Toxic Concentration Low, the lowest concentration of a gas or vapor capable of producing a defined toxic effect in a specified test species over a specified time.
TDL | Toxic Dose Low, lowest administered dose of a material capable of producing a defined toxic effect in a specified test species.
Temp | Temperature.
Ter | See Teratogen.
Teratogen | A substance or agent, exposure to which by a pregnant female, can result in malformation in the fetus.
Tfx | Toxic effect(s).
Thermal Decomposition | The breakdown of a material when heated.
Threshold Limit Value | TLV and PEL.  The Threshold Limit Value (TLV) is a safe exposure level set by the American Conference of Governmental Industrial Hygienists (ACGIH).  A Permissible Exposure Limit (PEL) is a simi ...
TIC | Toxic Industrial Chemical.
Time Weighted Average (TLV-TWA) | This is the time-weighted average concentration for a normal 8-hour workday or 40-hour workweek, in which all workers may normally be exposed day after day, without advance affect.
Tinnitus | A ringing or signing sound in the ears.
TLV | See Threshold Limit Value.
TOC | TAG Open Cup.  See Flash Point.
Torr | A unit of pressure, equal to 1/760 atmosphere.
Toxemia | A chemical falling within any of the following categories: A chemical with a median lethal dose (LD5O) of more than 50 milligrams per kilogram but not more than 500 milligrams per kilogram of body ...
Toxic Substance | Any substance which can cause acute or chronic injury to the human body, or which is suspected of being able to cause diseases or injury under some conditions.
Toxicity | The sum of adverse effects resulting from exposure to materials, generally by the mouth, skin, or respiratory tract.
Trade Name | The trademark name or commercial trade name for a material or product.
Transplacental | An agent that causes physical defects in the developing embryo.
TSCA | Toxic Substances Control Act (Federal Environmental Legislation administered by EPA) regulates the manufacture, handling, and use of materials classified as "toxic substances."
TWA | Time Weighted Average exposure is the airborne concentration of a material to which a person is exposed, averaged over the total exposure time, generally the total workday (8 to 12 hours).  Also, ...
UEL or UFL | Upper Explosive Limit or Upper Flammable Limit of a vapor or gas; the highest concentration (highest percentage of the substance in air) that will produce a flash of fire when an ignition source ( ...
Unstable | Tending toward decomposition or other unwanted chemical change during normal handling or storage.
Unstable Reactive | A chemical that, in the pure state, or as produced or transported will vigorously polymerize, decompose, condense, or become self-reactive under conditions of chocks, pressure, or temperature. ...
Urticaria | Nettle-rash; hives; elevated itching; white patches.
USDA | U.S. Department of Agriculture.
Uterus | A muscular organ, which holds and nourishes the growing fetus.
Vapor | The gaseous form of a solid or liquid substance as it evaporates.
Vapor Density | The weight of a vapor of gas compared to the weight of an equal volume of air is an expression of the density of the vapor or gas.  Materials lighter than air has vapor densities less than 1.0 (e ...
Vapor pressure | The pressure exerted by a saturated vapor above its own liquid in a closed container.  When qualifying control tests are performed on products, the test temperature is usually 100 degrees F, and ...
Ventilation | See General Exhaust, Local Exhaust and Mechanical Exhaust Ventilation.
Vermiculite | An expanded mica (hydrated magnesium-aluminum-iron silicate) used as sorbent for spilled control and clean up.
Vertigo | A feeling of revolving in space; dizziness, giddiness.
Viscosity | Resistance to flow exhibited by a fluid.
Volatility | A measure of how quickly a substance forms a vapor or ordinary temperature.
Water Disposal Methods | Proper disposal methods for contaminated material, recovered liquids, or solids, and their container.
Water-reactive | A chemical that reacts with water to release a gas that is either flammable or presents a health hazard.
Work Area | A room or defined space in a workplace where hazardous chemicals are produced or used, and where employees are present.
Workplace | An establishment at one geographical location containing one or more work areas.
Zinc Fume Fever | A condition brought on by inhalation of zinc oxide fume characterized by flulike symptoms with a metallic taste in the mouth, coughing, weakness, fatigue, muscular pain, and nausea, followed by fe ...