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Occupational Safety Management Sacramento State University

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NFPA Guidelines & Definitions

Skin Irritation

Ratings corresponding to the following definitions are derived from data obtained from the test methods as described in 16 CFR 1500.41 and/or NAS Publication 1138, and categories of toxicity as described in 16 CFR 1500.3.

  1. Practically Non-Irritating: The undiluted product causes no noticeable irritation, or causes slight inflammation (edema and erythema skin reaction values of 0 or 1) of intact or abraded skin of rabbits during the study period. Primary Irritation Index of 0- 1.9.
  2. Moderately Irritating: The undiluted product causes well-defined inflammation (edema and erythema skin reaction values of 2) during the study period. Primary Irritation Index of 2-4.9.
  3. Primary Skin Irritant: The undiluted product causes moderate to severe inflammation (edema and erythema skin reaction values of 3 or 4) of the intact or abraded skin of rabbits during the study period. Primary Irritation Index of 5 or more.
  4. Corrosive: The undiluted product causes visible destruction or irreversible alterations of the tissue structure at the site of contact on intact or abraded skin of rabbits during the study period.

Eye Irritation

Ratings corresponding to the following definitions are derived from data obtained from test methods described in the 16 CFR 1500.42 graded pursuant to the Draize Scale for scoring ocular lesions and temporal reversibility criteria as set forth in NAS Publication 1138.

  1. Practically Non-Irritating: The undiluted product, when instilled into the eyes of rabbits, produces no noticeable irritation, or slight transient conjunctival irritation. (Average Draize score range 0.00-15.0).
  2. Slightly Irritating: The undiluted product, when instilled into the eyes of rabbits, produces slight to moderate conjunctival irritation, slight corneal involvement, and/or slight iritis. (Average Draize score range 15.1-25.0). The effects clear within 7 days.
  3. Moderately Irritating: The undiluted product, when instilled into the eyes of rabbits, produces moderate corneal involvement with or without severe iritis. (Average Draize score range 25.1-50.0). The effects clear within 21 days.
  4. Severely Irritating (or Corrosive): The undiluted product, when instilled into the eyes of rabbits, produces severe corneal involvement with or without severe iritis. (Average Draize score range 50.1-110.0). The effects persist for 21 days or more.

Oral Toxicity

Ratings corresponding to the following definitions are derived from data obtained from the test methods and categories of toxicity as described in 16 CFR 1500.3.

  1. Non-Toxic: The probable lethal dose of undiluted product to 50% of the test animals determined from ingestion studies (LD50) is greater than 5 grams per kilogram of body weight.
  2. Toxic: The probably lethal dose of undiluted product to 50% of the test animals determined from ingestion studies (LD50) is greater than 50 milligrams and less than or equal to 5 grams per kilogram of body weight.
  3. Highly Toxic: The probably lethal dose of undiluted product to 50% of the test animals determined from ingestion studies (LD50) is less than or equal to 50 milligrams per kilogram of body weight

Dermal Toxicity

Ratings corresponding to the following definitions are derived from data obtained from the test methods as described in 16 CFR 1500.40, and categories of toxicity as described in 16 CFR 1500.3.

  1. Non-Toxic: The probably lethal dose of undiluted product to 50% of the test animals determined from dermal toxicity studies (LD50) is greater than 2 grams per kilogram of body weight.
  2. Toxic: The probably lethal dose of undiluted product to 50% of the test animals determined from dermal toxicity studies (LD50) is greater than 200 milligrams and less than or equal to 2 grams per kilogram of body weight.
  3. Highly Toxic: The probably lethal dose of undiluted product to 50% of the test animals determined from dermal toxicity studies (LD50) is less than or equal to 200 milligrams per kilogram of body weight.

Inhalation Toxicity

Ratings corresponding to the following definitions are derived from the test methods and categories of toxicity described in 16 CFR 1500.3.

  1. Non-Toxic: The probably lethal concentration of the undiluted product to 50% of the test animals (LC50) is greater than 200 milligrams per liter by volume when inhaled continuously for one hour or less.
  2. Toxic: The probably lethal concentration of the undiluted product to 50% of the test animals (LC50) is greater than 2 milligrams and less than or equal to 200 milligrams per liter by volume when inhaled continuously for one hour or less.
  3. Highly Toxic: The probably lethal concentration of the undiluted product to 50% of the test animals (LC50) is less than or equal to 2 milligrams per liter by volume when inhaled continuously for one hour or less.