PHMSA letter of interpretation

Testing requirements for lithium batteries

Pipeline and Hazardous Materials Safety Administration · Mar 28, 2008 · Reference No. 07-0199

PHMSA says to use caution with this letter. On August 6th, 2014, PHMSA published Final Rule, HM-224F, which amends the regulations for lithium batteries. The rule harmonizes the HMR with many of the provisions in the UN Model Regulations, ICAO Technical Instructions, and IMDG Code. Additionally, the exceptions for small and medium lithium batteries formerly found in special provisions 188 and 189, have been moved to § 173.185(c). Please refer to the most recent version of § 173.185 for information on shipping lithium batteries. The most current version of the regulations can be found in the eCFR at www.ecfr.gov.

Interprets: 49 CFR § 173.56

Reggie’s quick take

A manufacturer asked whether the Department of Defense must test lithium batteries before shipping a device that contains them. The agency said no for small production run batteries sent to DoD and then built into a device, but not if the device will fly on a commercial aircraft. In that case, testing is required. The agency also said packages with small lithium cells and batteries must follow Special Provision 188 starting October 1, 2008. Under that provision, a device with an explosive and a small lithium battery that DoD found unregulated must still meet UN testing for batteries, starting October 1, 2009.

Written by AI (Claude) on Oct 22, 2026. Robots make mistakes and leave things out, so the letter below is what counts. Not legal advice.

This is in response to your October 11, 2007 letter regarding testing requirements for lithium batteries under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Your questions are paraphrased and answered as follows:

Q1. If a manufacturer ships a small production run of batteries to the Department of Defense (DoD) and DoD incorporates the batteries into a device, must DoD test the batteries before offering the device for transportation?

A1. No. Subsequent shipments of small production run batteries may be shipped under Special Provision 29. You should be aware that the exception for small production runs in Special Provision 29 does not apply to transportation by aircraft. Therefore, if DoD intends to ship the devices via commercial aircraft, testing of the batteries is required.

Q2. When transporting a device classified as an explosive that contains a primary lithium battery, do the new marking requirements for lithium batteries apply as amended in Docket HM 224C and HM 224E, published August 9, 2007 (72 FR 44929)?

A2. A device that contains an explosive must be examined and approved by the Associate Administrator for Hazardous Materials Safety in accordance with § 173.56(b). In the future, approvals issued by the Associate Administrator for devices containing explosives and lithium batteries will specify the marking requirements. Effective October 1, 2008, packages containing small lithium cells and batteries must be marked in accordance with Special Provision 188, including those classified by the DoD in accordance with § 173.56(b)(2).

Q3. DoD has a device containing an explosive and a small lithium battery. The device was examined and determined to be non regulated based on the size of the battery. Is DoD required to perform UN testing on the battery device based on the new requirements promulgated under Docket HM 224C?

A3. Yes. In accordance with Special Provision 188, effective October 1, 2009, the battery must be of a type proven to meet the requirements of each test in the UN Manual of Tests and Criteria for transport as Class 9 or excepted.

I hope this information is helpful. If you have further questions, please do not hesitate to contact this office.

A letter of interpretation applies the regulations to the facts the requester described. It isn’t a regulation and isn’t legal advice. The agency’s copy.