Overpacking Small Quantities

This responds to your letter, postmarked December 14, 2007, concerning requirements in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to small quantity shipments. Specifically, you ask about requirements applicable to packages prepared in accordance with § 173.4 and overpacked in a fiberboard box. Your questions are paraphrased and answered as follows:

Q1. If packages conforming to the requirements in § 173.4 are overpacked in a fiberboard box, must the overpack successfully pass the package testing requirements specified in § 173.4(a)(6)?

A1. No. The package testing requirements apply to the packaging configurations specified in § 173.4.

Q2. If packages conforming to the requirements in § 173.4 are overpacked in a fiberboard box, must the overpack be marked "This package conforms to 49 CFR 173.4"? If not, must the overpack be marked "OVERPACK"?

A2. The marking specified in § 173.4 is the shipper's statement certifying that a package conforms to the requirements set forth in that section. No certification mark is required for the overpack. Further, packages prepared in accordance with § 173.4 are excepted from all other HMR requirements. Thus, the marking requirements in § 173.25 applicable to overpacks do not apply to overpacks containing packages prepared in accordance with § 173.4.

Q3. May the overpack exceed the 29 kg gross weight limit specified in § 173.4(a)(8)?

A3. Yes. The weight limitation applies to individual packages prepared in accordance with § 173.4.