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Interpretation Response #16-0144 ([ERM] [Scott Porter])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: ERM

Individual Name: Scott Porter

Location State: CO Country: US

View the Interpretation Document

Response text:

March 03, 2017

Scott A. Porter
Senior Project Scientist
555 17th Street, Suite 1700
Denver, CO 80202

Reference No. 16-0144

Dear Mr. Porter,

This letter is in response to your August 19, 2016, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to determining the reportable quantity (RQ) of a hazardous substance. You provide a scenario in which nickel powder with a mean particle size of 101.1 micrometers is being shipped in a packaging totaling 1 metric ton. Specifically, you ask whether the mean particle size can be used to determine if the nickel powder meets the RQ of a hazardous substance or whether the amount of nickel powder with a particle size exceeding the threshold size (i.e., 100 micrometers) must be determined.

The answer is no; the mean particle size cannot be used to determine if the nickel powder meets the RQ. When determining whether a material in a package meets the RQ listed in Table 1 to Appendix A of § 172.101 (i.e., the hazardous substances table), the actual particle size must be used. The "¢" symbol associated with the entry "Nickel" in Table 1 denotes that the RQ is limited to metal particles having a diameter smaller than 100 micrometers. To meet the RQ for nickel, a package containing nickel must contain at least 100 pounds of nickel particles less than 100 micrometers. Based on the information you provided, we cannot determine whether your shipment meets the definition of a hazardous substance.

I hope this information is helpful. Please contact us if we can be of further assistance.



Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table