Environmental Health & Safety

Definitions and Guidelines

1. Definitions

Standard Operating Procedures (SOPs) are written safety and health guidelines required for work with hazardous chemicals. "Hazardous chemicals" are defined as having statistically significant evidence based on at least one study conducted in accordance with established scientific principles that acute or chronic health effects may occur in exposed employees.

Included in the definition of hazardous chemical is a select group of chemicals that will require additional handling provisions. This group is referred to in the Laboratory Safety Standard as "particularly hazardous substances" and includes chemicals that meet any of the following criteria:

a.    High degree of acute toxicity:

The Environmental Protection Agency (EPA) has adopted the following criteria to identify acutely toxic chemicals based on data from mammalian testing.

i.      Dermal route: the median lethal dose (LD50) is less than or equal to 50 mg/kg.

ii.    Oral route: the median lethal dose (LD50) is less than or equal to 25 mg/kg.

iii.   Inhalation route: the median lethal concentration (LC50) is less than or equal to 0.5 mg/l where time of exposure is any time up to 8 hours.(LD50) is a single dose of a material expected to kill 50% of a group of test animals. (LC50) is a calculated concentration of a material in air, exposure to which for a specified length of time is expected to cause death of 50% of a defined experimental animal population.

b.    Select carcinogens:

i.      listed as "known to be carcinogens" in the Annual Report on Carcinogens published by the National Toxicology Program (NTP) (latest edition), or

ii.    listed under Group 1 ("carcinogenic to humans") by the International Agency for Research on Cancer (IARC) Monographs (latest editions), or

iii.   listed in either Groups 2A or 2B by IARC or under the category, "reasonably anticipated to be carcinogens" by the NTP, and causes statistically significant tumor incidence in experimental animals in accordance with any of the following criteria:

·         after inhalation exposure of 6-7 hours per day, 5 days per week, for a significant portion of a lifetime to dosages of less than 10 mg/m3; or

·         after repeated skin application of less than 300 mg/kg of body weight per week; or

·         after oral dosages of less than 50 mg/kg of body weight per day.

iv.   listed as a DOSH regulated carcinogen in WAC 296-62-073(see Appendix K).

v.    substances listed as confirmed (A1) or suspected (A2) human carcinogens in the most current version of ACGIH Threshold Limit Values.

See the Addendum to Appendix K, the "List of Known Carcinogens and Non-Carcinogens," for further information.

c.    Reproductive Toxins (See Appendix L)

Reproductive Toxins are chemicals that affect the reproductive capabilities of males or females including chromosomal damage (mutations) and fetal effects (teratogenesis). Safety Data Sheets generally employ the following keywords to designate a reproductive toxin: congenital malformation, fetal toxicity, fetal death, fatal effects to the newborn, neoplastic, teratogenic, mutagenic, maternal effects, paternal effects, fertility and infertility. Use Appendix L or Safety Data Sheets (SDSs) to help in determining whether a chemical may be a reproductive toxin. Appendix L was generated from the Hazardous Substances Databank (HSDB), a database of the National Library of Medicine's TOXNET System and from the Catalog of Teratogenic Agents by T.H. Shepard.

d.    To aid in determining whether a chemical is hazardous or particularly hazardous, use the links available through Appendix K, Appendix L, and SDSs. If assistance is needed or questions arise, contact EH&S at 335-3041.

2. Guidelines

Standard Operating Procedures (SOPs) are required to be written for chemicals currently in use in the laboratory. When new chemicals are introduced for use they must be included in existing SOPs or in a new SOP. EHS has several hundred SOP templates for various hazardous chemicals for you to use in developing your SOP.

In Appendix M there are examples of Standard Operating Procedure formats and the required Hazard Assessment certification and training documents for PPE. If you already have SOPs for pieces of equipment, chemical processes, mixture preparation, etc., attach those to this portion of the Chemical Hygiene Plan (CHP).


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