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Interpretation Response #23-0096

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

Interpretation Response Details

Response Publish Date:

Company Name: Airborne Labs International, Inc.

Individual Name: Aniyah Volpe

Location State: NJ Country: US

View the Interpretation Document

Response text:

March 27, 2024

Aniyah Volpe
Shipping Administrator Coordinator
Airborne Labs International, Inc.
22C World’s Fair Drive
Somerset, NJ 08873

Reference No. 23-0096

Dear Ms. Volpe:

This letter is in response to your October 26, 2023, email and subsequent conversation with a member of my staff requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to customer shipments of carbon dioxide (CO2) sent to your company laboratory for quality control testing of a liquid CO2 source. Specifically, your company provides sampling kits, accompanied by specific instructions, for the collection and shipment of non-liquid phase CO2 in bags and mini-cylinders. You note that the CO2 samples collected in the sample bags are essentially at atmospheric pressure, and the CO2 in the sample mini-cylinders is at 25 psig or less, when the mini-cylinders incorporate a check valve to limit the pressure of the contents. It is your understanding, based on the classification criteria for Division 2.2 gases, that CO2 transported in containers at these pressures is not regulated as a hazardous material and request confirmation.

Your understanding is correct. While CO2 is listed in the § 172.101 hazardous materials table as a Division 2.2 gas, the CO2 as described in your email does not meet the definition of a Division 2.2 gas when transported in a container at pressures below 29.0 psig at 68 °F (20 °C), nor is it transported as a liquified gas or cryogenic liquid (see § 173.115(b)). Furthermore, it would remain not regulated, provided that it does not meet the criteria for a hazardous waste, hazardous substance, marine pollutant, or any other hazard class or division.

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

172.101, 173.115(b)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.115 Class 2, Divisions 2.1, 2.2, and 2.3-Definitions