Details of the Aircraft Hangar:
We need to protect an Aircraft Hangar - Group 1 as per NFPA 409. Our protection scheme is Option 1. Foam water deluge system shall be installed under roof ceiling as primary protection & Low expansion foam monitors as secondary protection.
Hangar Classification - Group 1
Protection Scheme - Option 1
Primary Protection - Foam Water Deluge Systems
Secondary Protection - Low expansion foam monitors
NFPA 409 - Question about fire water supply calculation:
Section 220.127.116.11 - the concentrate for the foam expansion deluge system shall be sufficient for 10 minutes foam discharge.
Section 18.104.22.168 - the total water supply duration shall be minimum for a duration of 45 minutes when supplementary systems are installed.
Please confirm, the water quantity for the protection is,
a) design density in LPM x Operational Area x 45 Minutes (sufficient for compliance to 22.214.171.124 and 126.96.36.199)
b) design density in LPM x Operational Area x 10 Minutes (sufficient only for compliance to 188.8.131.52)
Thanks in advance,