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Interpretation Response #11-0088 ([Honeywell International, Inc.] [Ms. Carrie Wayne])

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

Interpretation Response Details

Response Publish Date:

Company Name: Honeywell International, Inc.

Individual Name: Ms. Carrie Wayne

Location State: NJ Country: US

View the Interpretation Document

Response text:

June 7, 2011

Ms. Carrie Wayne
Honeywell International, Inc.
101 Columbia Road
Morristown, NJ 07962

Ref. No.: 11-0088

Dear Ms. Wayne:

This responds to your April 11, 2011 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to Class 2 materials. Your questions are paraphrased and answered below.

Q1: You ask whether a material must meet all three provisions in § 173.115(b)(1) through (b)(2) to be a classified as a Division 2.2 material?

A1: The answer is no. As specified in § 173.115(b), the HMR define a Division 2.2 (non-flammable, nonpoisonous compressed gas - including compressed gas, liquefied gas, pressurized cryogenic gas, compressed gas in solution, asphyxiant gas and oxidizing gas) as any material or mixture that "exerts in the packaging a gauge pressure of 200 kPa (29.0 psig/43.8 psia) or greater at 20 °C (68 °F), is a liquefied gas or is a cryogenic liquid, and does not meet the definition of Division 2.1 or 2.3."

To be considered a Division 2.2 material, a material would only need to meet one of the provisions in § 173.115(b)(1) (i.e. exerts a gauge pressure =200 kPa at 20 °C, is a liquefied gas or a cryogenic liquid) and not meet the definition of Division 2.1 or 2.3 material.

Q2: You ask whether a liquefied gas, irrespective of its pressure, meets the definition of a Division 2.2 material?

A2: The definition of a Division 2.2 gas includes all liquefied gases, irrespective of their pressures. This is due to the fact that certain liquefied gases that pose no pressure hazard at ambient pressures and temperatures may exhibit a pressure hazard under conditions normally encountered in transport, such as increased temperature.

Q3: You ask whether your hazardous material (gas) must be "compressed" in order to be described as a refrigerant gas?

A3: As specified in § 173.115(j), the terms "Refrigerant gas and Dispersant gas" apply to all nonpoisonous refrigerant gases; dispersant gases (fluorocarbons) listed in § 172.101 of the HMR and §§173.304, 173.314(c), 173.315(a), and 173.315(h) and mixtures thereof; and any other compressed gas having a vapor pressure not exceeding 260 psia at 54 °C (130 °F), used only as a refrigerant, dispersant, or blowing agent.

If your gas exerts any pressure, meets the criteria of a compressed gas having a vapor pressure not exceeding 260 psia at 54 °C (130 °F), and is used only as a refrigerant, dispersant, or blowing agent, it could be referred to as a Refrigerant gas and Dispersant gas.

I trust this satisfies your inquiry. Please contact us if we can be of further assistance.


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

173.115, 172.101

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