A 60 bulkhead or deck
A 60 bulkhead or deck means an A class bulkhead or deck that
- Is insulated with approved insulation, bulkhead panels, or deck covering;
- If subjected to the standard fire test for 60 minutes, has an average temperature rise on the unexposed side of the insulated bulkhead or deck of less than 139 °C (250 °F) above the temperature before the standard fire test and has a temperature rise at any point on the unexposed surface, including any joint, of less than 180 °C (325 °F) above the temperature before the standard fire test.
Source: Mobile Offshore Drilling Units, 46 CFR 107-109 (2013). Regulations