39.Class of bulkheads and locations.

Class A

• Are divisions forming bulkheads and decks that are;
  • Constructed of steel or equivalent
  • suitably stiffened
  • Prevent passage of smoke and flame to the end of one hour standard fire test
  • Insulated using non-combustible material so that average temperature on un-exposed side does not rise above 139^o C and point temperature above 180^o The time duration for which the bulkhead complies with this , governs its class
    A-60— 60 Min
    A-30— 30 Min
    A-15 —15 Min
    A-0 —0 Min

Class B

• These are divisions formed by bulkheads, decks, ceilings and lining
  • Prevent passage of flame for first half hour of standard fire test
  • Insulated so average un-exposed side temperature does not rise more than 139^oC above original and no single point rises more than 225^oC above original .
  • B-15 -15 Min
    B-0 -0 Min
  • Constructed of non-combustible material and all materials entering the construction are similarly non-combustible except where permitted.

Class C

• These are divisions constructed of approved non-combustible materials. Combustible veneers are allowed where they meet other criteria
• Main vertical zones Divided by Class A bulkheads and not exceeding 40m in length

Locations

Exterior boundaries of super structure and deck house enclosing accommodation and service space must be of Class A 60.

Bulkhead separating spaces in accommodation can be of A 60 to Class C
All non boundary bulkhead is of Class B or C