BS M 88:1996

This standard BS M 88:1996 Air cargo equipment. Pressure equalization requirements for cargo containers is classified in these ICS categories:

• 49.120 Cargo equipment

Since most modern civil transport aircraft capable of carrying air cargo unit load devices or large-size shipping containers have pressurized cabins and cargo compartments, two different cases must be considered:

1. normal (low airflow) pressure equalization during climb and descent – from the departure airport pressure down to the cruise flight cabin pressure, up to the landing airport pressure;
2. emergency (rapid decompression) pressure equalization in the event of a sudden (possibly “explosive”) depressurization of the aircraft fuselage occurring at cruise altitude: this case requires very fast (high airflow) pressure equalization between cruise flight cabin pressure and outer ambient pressure.

This International Standard defines the minimum safety requirements to be met by containers used to transport cargo by civil transport aircraft in either case a) or b) above.

The flight safety requirements specified in this International Standard are applicable to the design of

• aircraft containers for general cargo, as covered by
  • ISO 4118 for non-certified lower deck containers,
  • ISO 6517 for base-restrained certified containers exclusively for the lower deck of high-capacity aircraft,
  • ISO 8323 for air/surface intermodal containers,
  • ISO 10327 for certified containers for air cargo;
• air mode insulated containers, as covered by ISO 8058;
• any airtight shipping containers with an internal volume of 1 m³ (35 ft³) or more.

NOTE 1 Most shipping containers/packagings used for air cargo are made of sufficiently low-strength material (e.g. fibreboard) or provide sufficient air leakage (e.g. wooden crates) that they cannot be considered airtight and do not present any significant hazard as a result of pressure equalization.

There are however a number of special containers, notably for the carriage of satellites/space hardware, aircraft spares, sensitive scientific or technical equipment, etc., which are airtight per design (in order to protect the contents against atmospheric pollution) or per construction (because of the quality of sealing and materials used).