Ask X3What does 49 CFR 173.116 (Class 2—Assignment of hazard zone) require?
Generated guidance. Confirm the source and its applicability before you act. How we check sources.
According to 49 CFR 173.116, the hazard zone for a Class 2, Division 2.3 material is assigned in column 7 of the § 172.101 table (note that Divisions 2.1 and 2.2 have no hazard zones).
When the table provides more than one hazard zone for a Division 2.3 material—or requires it to be determined based on grouping criteria—you must determine the hazard zone by applying the following inhalation toxicity criteria (which are also represented graphically in § 173.133, Figure 1):
* Hazard Zone A: An $\text{LC}_{50}$ less than or equal to 200 ppm.
* Hazard Zone B: An $\text{LC}_{50}$ greater than 200 ppm and less than or equal to 1000 ppm.
* Hazard Zone C: An $\text{LC}_{50}$ greater than 1000 ppm and less than or equal to 3000 ppm.
* Hazard Zone D: An $\text{LC}_{50}$ greater than 3000 ppm and less than or equal to 5000 ppm.