PHMSA Study on Aerosol Products

Written on: May 1, 2019 by Nicholas Georges

For consumers and workers around the world, aerosol products are convenient packages that are safe, efficient and easy to use. The unique packaging form allows a wide range of products to be dispensed in a variety of sprays. Manufacturers and marketers are able to innovate products and deliver them to consumers and workers, providing benefits that help to improve their lives both at home and in the workplace.

For the end-user, the aerosol product is simple—a button is pushed, the product ejects its contents and the desired job is accomplished. However, for aerosol manufacturers, making aerosol products is not a simple task and there are inconsistencies between global laws and regulations that make it even more difficult.

In an effort to harmonize U.S. regulations, the Household & Commercial Products Association (HCPA)1, Council on Safe Transportation of Hazardous Articles, Inc. (COSTHA), National Aerosol Association (NAA) and American Coatings Association (ACA) petitioned the U.S. Dept. of Transportation (DOT) Pipeline & Hazardous Materials Safety Administration (PHMSA) in 2017 to align the Hazardous Material Regulations (HMR) with applicable international regulations by modifying the definition of an aerosol to include certain non-refillable gas containers with or without a liquid, paste or powder.
Currently, the HMR2 provides the following definition of an aerosol:

Aerosol means any non-refillable receptacle containing a gas compressed, liquefied or dissolved under pressure, the sole purpose of which is to expel a nonpoisonous (other than a Division 6.1 Packing Group III material) liquid, paste, or powder and fitted with a self-closing release device allowing the contents to be ejected by the gas.

This definition is inconsistent with the definition of an aerosol found in the United Nations Model Regulations (UNMR), the International Maritime Dangerous Goods (IMDG) Code, the International Civil Aviation Organization Technical Instructions on the Safe Transport of Dangerous Goods by Air (ICAO TI) and the Regulations governing European Road Transport (ADR).

Without the alignment of definitions, the aerosol industry will have to continue to utilize special permits to authorize small, pressurized containers of various gases to be reclassified as limited quantity and shipped with very broad exceptions. Some of these special permits, DOT-SP 10232, for example, have been around for decades. The shipment of products under special permits and classifications has shown excellent safety in distribution and market; otherwise, the industry wouldn’t be able to continue to utilize them.

However, using special permits is an extra burden upon shipping gas-only aerosol products that other aerosol products do not have. Aligning the definitions of an aerosol would relieve manufacturers and the channels of distribution from the special permits’ extra requirements.

In February 2019, PHMSA’s Office of Hazardous Materials Safety (OHMS) contracted with Cambridge Systematics to conduct a risk assessment for the transportation of aerosol products to align the U.S. and international regulations. The purpose of the risk assessment is to determine if the UNMR definition of aerosols maintains an equivalent level of safety to the HMR definition and to assess potential risks associated with aligning the HMR with the UNMR.
Cambridge Systematics’ scope of work includes:

1. A literature review and to identify industry stakeholders at
respected trade organizations for interviews;
2. A supply chain analysis by identifying historical
transportation routes, conveyances, frequencies and
quantities; and
3. A risk analysis for potential consequences that could
potentially result from incidents involving the transport of
aerosols, and an analysis of relevant losses and incidents
involving flammable gases during transport.

Cambridge Systematics is expected to complete its study around February 2020. If it recommends to PHMSA that the harmonization of the definition of an aerosol found in the HMR with the UNMR ensures an equivalent level of safety, PHMSA would be expected to initiate a rulemaking for the alignment. This alignment would reduce the burden on the industry and eliminate the need for special permits that allow for gas-only aerosol products to be offered under transportation exceptions.

Modifying the current definition in the HMR is a step in the right direction to reduce regulatory burdens on the aerosol industry, but there are also other opportunities. These opportunities include allowing the use of alternative technologies to the hot water bath test3, reducing regulatory barriers to plastic aerosol products4 and moving to solely a performance-based standard for metal containers5. We respectfully encourage you to get involved to help the aerosol industry align domestic regulations with international regulations. These efforts would greatly assist in not only reducing regulatory burdens, but equally important, they would help to maintain the safety record of the U.S. aerosol industry. This will almost undoubtedly make it easier for consumers and workers to purchase and obtain the aerosol products that improve daily life. Please do not hesitate to contact us at and for more information. SPRAY

1 At the time known as the Consumer Specialty Products Association (CSPA)
249 CFR §171.8
349 CFR § 173.306
449 CFR § 173.306(a)(5), 49 CFR § 178.33b-5, and 49 CFR § 178.33b-6
549 CFR § 178.33-7, 49 CFR § 178.33a-7