Guidelines for care & Use of Dry Solvent Stills [Example]

F. Provisions for Additional Protection When Working with Particularly
Hazardous Chemicals
The OSHA Laboratory Standard, besides stipulating that a Chemical Hygiene Plan be written for each lab,
requires you to be particularly careful in handling what are referred to as "particularly hazardous
chemicals." These include "select" carcinogens, reproductive toxins, and substances which have a high
degree of acute toxicity.
"Select" carcinogens are defined in 29 CFR 1910.1450(b), as indicated on page 221 of Prudent
Practices, 2nd edition. See also page 203 of that monograph, section 9.C.4, for a more elaborate
description of regulated reproductive toxins and highly toxic substances. Please note that newly synthesized
chemicals in research laboratories are considered highly toxic until proven otherwise.
Each particularly hazardous chemical will be identified as such for you within the Chemistry
Department’s MSDS sheet Inventory, on the sheet itself, written by the manufacturer of the chemical in
question.
It is advisable to gather all "select" carcinogens which are present in your laboratory, label them
with yellow tape marked "Danger: Chemical Carcinogen" (commercially available), and store them in a
designated storage area for carcinogens in your lab, preferably a hood or a safe storage cabinet.
All reproductive toxins in your inventory should be labeled with commercially available orange
tape marked "Danger: Mutagen or Teratogen.” You would be well advised to store these in the same
storage area for carcinogens, although it may not always be possible to identify all of your teratogens since
published lists of these compounds are less specific than lists of carcinogens.
Highly Acute Toxic Chemicals have been listed for you in your inventory, via HMIS/NFPA
toxicity ratings of 3 or 4, usually by the manufacturer. Also, they can generally be identified by the
manufacturer’s warning labels (danger! - Highly Toxic, Poison, etc.) While no specific secondary labeling
will be attached to chemical containers for highly acute toxic chemicals, you will be expected to adhere to
the special handling provisions listed below when working with them. There is no need to store them in a
designated storage area, although you should work with them only in a designated work area (in other
words, a hood).
See the Training section of this manual for an explanation of the Hazard Communication
Standard’s Hazard Material Identification System (HMIS) or National Fire Protection Association (NFPA)
hazard rating system. Under these systems, both hazard ratings are pretty much the same.
Most chemical manufacturers rate their chemicals. The Hazard Communication Standard requires
manufacturers to provide hazard evaluations in the form of MSDS sheets. All supply MSDS sheets with
hazard evaluations, but not all supply HMIS hazard ratings.
The present regulatory standard applicable to the Chemistry Department, which superseded the
Haz-Comm Standard, is called the “Laboratory Standard” and requires only that “particularly hazardous
chemicals” be worked with in designated areas. It only requires carcinogens and mutagens/teratogens to be
labeled.
Acute toxicity is rated from 0 to 4 in the HMIS/NFPA systems (0 less dangerous, 4 most
dangerous). One could regard those rated as 3 and 4 as chemicals with a “high degree of acute toxicity,”
thus combining the regulatory requirements for hazard assessment present in the Haz-Com standard and the
Laboratory standard, into one rating system, that is, the HMIS system.
Teratogens and mutagens are listed as chronically toxic chemicals, designated as the letter “T” for
known teratogens and “t” for suspected teratogens. Known mutagens are “M”, suspected mutagens are
“m”. Allergens are “A” and substances which cause silicosis are “S”. Carcinogens are labeled as
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