Effective August 14, the FAA is amending Part 25 standards for airplane pressurized compartment loads to eliminate the need for partitions adjacent to a decompression hole to withstand large decompression conditions. The agency said this rulemaking is necessary because “in some cases, it is not practical to design partitions in certain airplane compartments to withstand this decompression condition if it occurs within that compartment.”
FAR 25.365(g) requires applicants to design bulkheads, floors, and partitions in pressurized compartments for occupants to withstand certain sudden decompression conditions. Applicants are also required to take “reasonable design precautions” to minimize the probability of parts becoming detached and injuring seated occupants.
For some smaller compartments such as lavatories, private suites, and crew rest areas, it has been difficult for applicants to achieve compliance because a large decompression hole would result in very high air loads on the partitions that form the compartment. “Strengthening the partitions to sustain such high loads has been shown to be impractical in many cases for these smaller compartments because doing so could adversely affect the structural integrity of the airplane.”
The new rules allow partition failure if the certificate applicant can demonstrate such a failure “would not interfere with continued safe flight and landing.” The requirements are essentially unchanged from a notice of proposed rulemaking published in 2019 except for some terminology clarifications.