Guidance for Creating Chemical SOP’s

Identifying Particularly Hazardous Substances

Particularly hazardous substances, by MIOSHA definition, are select carcinogens, reproductive toxins and chemicals with a high degree of acute and chronic toxicity. MIOSHA has defined toxicological criteria for classification of substances for each of these definitions. At CMU, particularly hazardous substances can be identified as chemicals meeting one or more of the following Globally Harmonized System (GHS) hazard classifications:

  • Carcinogenicity (Category 1A) (Category 1B) (Category 2)
  • Reproductive Toxicity (Category 1A) (Category 1B) (Category 2)
  • Reproductive Toxicity (Effects on or via lactation)
  • Germ cell mutagenicity (Category 1A) (Category 1B) (Category 2)
  • Acute toxicity, oral (Category 1) (Category 2)
    • Not required for categories 3 and 4
  • Acute toxicity, dermal (Category 1) (Category 2)
    • Not required for categories 3 and 4
  • Acute toxicity, inhalation (Category 1) (Category 2)
    • Not required for categories 3 and 4
  • Specific target organ toxicity, single exposure (Category 1) (Category 2)
    • Not required for category 3

Hazard classifications are found in Section 2 of the Safety Data Sheet from the chemical manufacturer. If using a SDS database or online reference, be sure to match the SDS with the exact product in your lab. Oftentimes, the reagent in question may be mixed with a hazardous solvent or additive, which can present hazards not expected from the reagent alone.

Example: Hazard identification for the chemical chloroform is shown below. Chloroform is a Particularly Hazardous substance due to the Carcinogenicity (Category 2), Reproductive toxicity (Category 2), and Specific target organ toxicity - repeated exposure (Category 1) hazard classifications.


Hazard identification for the chemical chloroform

Establishing safe work practices for Particularly Hazardous Substances

MIOSHA Part 431. Hazardous Work in Laboratories mandates the establishment of specific provisions to protect employees who work with particularly hazardous substances.

The minimum mandatory provisions are described by MIOSHA as follows:

  • The establishment of a designated area or areas that indicate the physical limits of exposure to particularly hazardous substances
  • The use of containment devices, such as laboratory-type hoods or glove boxes.
  • Procedures for the safe removal of contaminated waste.
  • Decontamination procedures.

To satisfy the provisions required for work with particularly hazardous substances, the Office of Laboratory and Field Safety requires all laboratories who work with such substances to have a written plan detailing the provisions listed above. For this purpose, OLFS provides a template for faculty, staff, and lab employees to use for documentation of safety provisions as Standard Operating Procedures (SOPs) specific to their laboratory. SOPs must contain information specific to the designated laboratory and applicable to the workers in said laboratory.

Note: Some chemicals that do not meet the Particularly Hazardous Substance definition may be required to have written safety procedures for other hazard properties (e.g. pyrophorics, explosives, nanomaterials). Reference the Chemical Hygiene Plan for more information.

Developing and writing Standard Operating Procedures

Referencing information sources, including the CMU Chemical Hygiene Plan, Safety Data Sheets, and chemical safety literature, is highly recommended when creating SOPs for your lab. However, it is crucial to consider the information in the SOPs must be detailed and directly applicable to your laboratory. General descriptions of safe work practices or references to regulations or literature are not satisfactory. Furthermore, some information found in safety data sheets may be accurate, but ultimately not useful for lab employees. For example, some safety data sheets will advise use of respirators or breathing apparatus to prevent inhalation exposure. In practice, the vast majority of labs at CMU utilize fume hoods or glove boxes in place of respirators. If your lab does not utilize respirators, it would be inappropriate to prescribe use of respirators in an SOP for your lab.

 Standard Operating Procedure template with detailed instructions for each section