PROCEDURE FOR DETERMINING
FIRE FLOW DEMAND FOR UNSPRINKLERED FACILITIES
The following procedure shall be used to determine the required fire flow
demand and duration for buildings that are not fully sprinklered.
A. Step One - Determine the Classification of Occupancy. Appendix C
lists the classifications of occupancy hazard as Light, Ordinary Group 1,
Ordinary Group 2, and Extra.
B. Step Two - Determine the Water Demand Weighted Factors. The table is
divided into three weighted value categories for fire flow and duration in
each occupancy classification. These categories are determined from the
values established in the six factors discussed below. The final value is
determined by adding the values obtained from all six factors. See sample
calculations in Appendix D, par. D.
(1) Weighted Factors.
The six factors to be assigned weighted
values are as follows:
(a) Response Time by Fire Department. Most installations have
on-site fire departments which are familiar with hazards of buildings within
the facility. The longer the response time for manual fire fighting, the
greater the water demand and duration. Traffic flow is a factor and traffic
congestion is equivalent to a longer response distance. The fire department
response weighing factors are as follows:
Type of Fire Department Response
On-site (within 1 mile)
On-site (over 1 mile but less than 3 miles)
On-site (3 miles or greater)
Off-site (less than 2 miles)
Off-site (2 miles or greater)
(b) Type of Construction. Par. 2.1.4 requires that type of
construction comply with the UBC. As structural fire integrity is reduced,
water demand and duration will become greater. In addition, the
combustibility of construction will add to the water demand for an
unsprinklered building. The type of construction weighted values are as