Absorbent Material Under the Small Quantity Exception

This is in response to your July 29, 2002 letter regarding the small quantity exception requirements. Specifically, you are interested in the absorbent material requirements contained in § 173.4(a)(4) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

Your questions are paraphrased and answered as follows:

Q1. Does the inside of the outer packaging need to be lined with a cushioning or absorbent material?

A1. The HMR do not specifically state that the inside of the outer packaging must be lined with either cushioning or absorbent materials. The inner packagings must be so packed, secured, and cushioned, in a strong outside packaging, to prevent their breakage or leakage under conditions normally incident to transportation. In the event of leakage from a receptacle, the absorbent material must be capable of absorbing the entire content of that receptacle.

Q2. Does the absorbent material need to be capable of absorbing the contents of one receptacle or the entire content of the completed package?

A2. The absorbent must be capable of absorbing the entire content of all inner receptacles used as packaging for the hazardous materials (see § 173.4(a)(4)(ii)).

Q3. May the trays, each containing 25 inner receptacles, be placed in a plastic bag as a means of meeting the absorbent material requirement?

A3. No, you cannot meet the absorbent material requirement by using an impermeable barrier within the package to preclude leakage from the package.

Q4. Is there an external pressure where it would be acceptable for the absorbed liquid to be released from the absorbent material?

A4. No specific external pressure is provided in the HMR. However, the retained liquid must remain absorbed under conditions normally incident to transportation.