---
kind: "section"
citation: "49 C.F.R. § 178.512"
title: "49"
number: "178.512"
heading: "Standards for steel, aluminum or other metal boxes."
url: "https://uscodex.org/cfr/49/178.512"
---

# §178.512. Standards for steel, aluminum or other metal boxes.

- (a) **The following are identification codes for steel, aluminum, or other metal boxes—**
  - (1) 4A for a steel box;
  - (2) 4B for an aluminum box; and
  - (3) 4N for an other metal box.
- (b) **Construction requirements for steel, aluminum or other metal boxes are as follows—**
  - (1) The strength of the metal and the construction of the box must be appropriate to the capacity and intended use of the box.
  - (2) Boxes must be lined with fiberboard or felt packing pieces or must have an inner liner or coating of suitable material in accordance with [subpart C of part 173](/cfr/49/part173-subpartC.md) of this subchapter. If a double seamed metal liner is used, steps must be taken to prevent the ingress of materials, particularly explosives, into the recesses of the seams.
  - (3) Closures may be of any suitable type, and must remain secure under normal conditions of transport.
  - (4) **Maximum net mass—** 400 kg (882 pounds).

## Notes

### Amendments

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 59 FR 67521, Dec. 29, 1994; 78 FR 1096, Jan. 7, 2013]

### Source

Source: Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, unless otherwise noted.

### Authority

Authority: 49 U.S.C. 5101-5128; 49 CFR 1.81 and 1.97.

### Amendments

[Amdt. 178-97, 55 FR 52717, Dec. 21, 1990, as amended by Amdt. 178-106, 59 FR 67521, Dec. 29, 1994; 78 FR 1096, Jan. 7, 2013]