Reprinted from the ACJ - February, 1995
By now, we all regard ourselves as health and safety experts. Spouting studies, facts and figures, we assess hazards, decide on safety precautions and explain the procedures to our coworkers. We are very nearly self-taught industrial hygienists.
Well, at least we know how to pronounce the term and realize it's not the guys who clean the plant bathrooms. But what is it that sets them apart from us? The clean white lab coats? The clipboard and air sampling equipment? Perhaps their PhD in the subject?
Yes, all of these things stand between us and a career as an industrial hygienist. But what is the one essential thing that they have, the one source of knowledge that sets them apart? It's a handbook that explains the terms, abbreviations and nomenclature associated with industrial hygiene, hazard assessment and safety planning.
Face it, we can be wearing diapers and still impress people with words like anhydrous, exothermic and teratogen. Just think how stupefied they would be if we knew what those words meant.
So for the next episode or two, we are going to define a great many terms used in hazard assessment, MSDS reading, health care and protection. Then when we are done we can rip the pages out of this magazine, put on a lab coat and some thick glasses, and wander around the shop impressing ourselves and all those around us.
Let's start with a term used on almost all MSDS,
ACGIH _ American Conference of Governmental Industrial Hygienists. Yeah, the geeks in the white lab coats. They develop and recommend exposure limits for a myriad of chemicals and industrial hazards. Because they are not an actual branch of our government, they are very efficient and are often years ahead of the official government studies on these subjects. In fact, in 1989 or so, in a moment of brilliance, OSHA adopted the exposure limits suggested by ACGIH for several hundred industrial compounds. Thus saving themselves and us taxpayers millions of dollars. Prior to this, only 24 compounds had official, sanctioned limits. Anybody need a $600 hammer?
Acid _ A chemical with a pH of less than 7. It likes to give up H+ ions and because of this causes burns to living tissue. The lower the pH value, the stronger the acid.
Action Level _ A concentration of chemical that when found to be present by sampling requires OSHA regulations to kick in. An example would be that if the concentration of lead in your shop's air exceeds 30 ug/m3, employee monitoring, education and all the other lead standard regulations must be followed. Sampling that shows less than this concentration requires no action.
Acute Health Effects _ Adverse health effects that appear rapidly or with a single dose.
Absorb vs. Adsorb _ Absorb is the "sucking up" of a material into a substance. Adsorb is the "sticking" of a material to the surface of a substance.
Alkali _ It's like Kryptonite for that damn bunny on TV. Actually, it's another term for a "base" or "caustic," a compound with a pH greater than 7. Alkali compounds cause burns to living tissue. Maybe we can soak that bunny in a vat of it.
Anhydrous _ Means without water. Never dive into an anhydrous swimming pool.
Asphyxia _ A lack of oxygen in the blood stream. Certain chemicals, fumes or a plastic bag over your head can cause asphyxiation.
BEI _ Biological Exposure Index. It's a list of substances and their tendency to be absorbed into our bodies.
Centigrade or Celsius _ Temperature scale (C) using 0 as the temperature of freezing water and 100 as that of boiling water. It converts to Fahrenheit this way, F=(C)5/9+32.
Carcinogen _ A substance that causes cancer in humans or is considered a cancer risk in humans because it causes cancer in lab animals. Never mind that they make a rat drink 55 gallons of the stuff when the normal exposure may be on the order of parts per million (ppm). If it shows any cancerous traits, it is a carcinogen. Remember, it's the dose that makes the poison.
CAS # _ For identification purposes, each chemical compound is given a unique number by the Chemical Abstract Society (ACS).
CERCLA _ The Comprehensive Environmental Response, Compensation and Liability Act. Also known as Superfund. Also known as the foremost sampling, monitoring and assessment fund. The actual clean-up aspect of the program has been criticized as too slow.
CFR _ This is like the guy with the best notes from the lecture. Only the CFR keeps track of the proposal of new laws, arguments against, compromises reached and the final form any given law will take.
Chelating Agent _ That's the person who gets your plane tickets and reservations on your chelating vacation. Let's hope you never have to take a chelating vacation. It's expensive and no fun. Chelation is performed to isolate and remove heavy metal ions from your bloodstream. Most commonly, it is employed for treatment of massive lead poisoning. Chemicals used for chelation, such as EDTA, have a greater attraction for metal ions than your blood molecules do. So the ions leave your bloodstream attached to the agent and are then excreted from your body.
CHEMTREC _ Who ya' gonna call? The Chemical Manufacturers Association (CMA) has set up an extensive data base on chemical emergency response. This info and the operators standing by 24 hours a day to dispense it is what CHEMTREC is all about. Don't call the number for routine info or they will charge you.
Chronic _ This term relates to an adverse health effect that develops over time.
Combustible _ A lower grade flammable. It will burn, just not as easy. Actual definition is a substance with a flash point greater than 100 F but less than 200 F.
Cutaneous _ A non-ugly taneous. Actually, pertaining to the skin. Thus subcutaneous refers to below the skin.
Dermatitis _ Is a catchall phrase for irritation of the skin. So your next case of chapped skin could be referred to as cutaneous dermatitis. Of course, no one will shake hands with you.
Epidemiology _ The overall study of a disease in a general population. So they know nothing about individuals, but can give tons of information on averages of a study group. Doesn't help much with crazed mailmen, though.
Exothermic _ This a process that gives off heat. Usually, it is a chemical reaction. Mixing dry zinc chloride or caustic soda with water will generate heat, and so is considered exothermic.
Flammable Limits _ Also referred to as Explosive Limits, upper (uel) and lower (lel). They are the upper concentration and the lowest concentration of a flammable gas that can sustain burning. Above the uel, the air/gas mixture is too rich, and below the lel, the mixture it is too lean.
Flash Point _ This is the minimum temperature that allows enough vapor to rise off a substance to burn. It is simply the lowest temperature that allows enough fumes to escape to reach the lel.
Fugitive Emissions _ Any vapor, mist or fume that is given off by a process, tank, equipment or escaped convict.
Fume _ Airborne dispersion of particles released as a liquid or solid is heated. Fumes can be flammable, such as some gas tank liners, or not, as in lead fumes.
Gram _ 454 of them equals one pound, especially in Europe.
That's all the time we have today. We'll be back next month with more definitions that will benefit us in two ways. First, we will be able to hold impressive conversations with cute nurses in bars. Secondly, when you see that next month's Health Watch is more of this drivel, you will spend extra time reading the other excellent articles in this magazine, therfore furthering your education.
The above article was written by David M. Brown, Chief Engineer of Johnson Manufacturing Company, Inc. and is published by JOHNSON with the expressed approval of the National Automotive Radiator Service Association and the Automotive Cooling Journal. Other reproduction or distribution of this information is forbidden without the written consent of JOHNSON and NARSA/ACJ. All rights reserved.
JOHNSON MANUFACTURING COMPANY
114 Lost Grove Road / PO Box 96 / Princeton, Iowa 52768-0096
Phone 563-289-5123 or Fax 563-289-3825