09/03/2026
Rev 4 isn't just a version number. It's the current standard for writing high-consequence procedures. If your program is still working to an older revision, the gap matters more than it looks.
PPA AP-907-005 Revision 4 reflects what the industry has learned about human performance: how people actually read, interpret, and act on a procedure under real conditions. Each revision sharpens that understanding. Rev 4 is where it stands today.
Here's why keeping current isn't just administrative housekeeping. A procedure written to an older standard can be technically correct and still carry the ambiguity, formatting, and level-of-detail issues that newer guidance was specifically designed to eliminate. The standard advanced because the understanding of how procedures fail advanced. Working to the current revision means your procedures reflect the current understanding of how to keep the person using them safe.
If your procedures were built to an earlier standard, it's worth asking when they were last measured against where the standard is now.