Site Feedback

Title 49

Displaying title 49, up to date as of 9/24/2021. Title 49 was last amended 9/13/2021.

Title 49

eCFR Content

The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. The Electronic Code of Federal Regulations (eCFR) is a continuously updated online version of the CFR. It is not an official legal edition of the CFR.

Learn more about the eCFR, its status, and the editorial process.

§ 173.116 Class 2 - Assignment of hazard zone.

(a) The hazard zone of a Class 2, Division 2.3 material is assigned in column 7 of the § 172.101 table. There are no hazard zones for Divisions 2.1 and 2.2. When the § 172.101 table provides more than one hazard zone for a Division 2.3 material, or indicates that the hazard zone be determined on the basis of the grouping criteria for Division 2.3, the hazard zone shall be determined by applying the following criteria:

Hazard zone Inhalation toxicity
A LC50 less than or equal to 200 ppm.
B LC50 greater than 200 ppm and less than or equal to 1000 ppm.
C LC50 greater than 1000 ppm and less than or equal to 3000 ppm.
D LC50 greater than 3000 ppm or less than or equal to 5000 ppm.

(b) The criteria specified in paragraph (a) of this section are represented graphically in § 173.133, Figure 1.

[Amdt. 173-224, 55 FR 52634, Dec. 21, 1990, as amended at 56 FR 66268, Dec. 20, 1991; Amdt. 173-138, 59 FR 49133, Sept. 26, 1994; 67 FR 61013, Sept. 27, 2002]