Portable extinguishers, IBC 2021 3309.1
A structure under construction, alteration or demolition needs not fewer than one approved portable fire extinguisher complying with Section 906, sized for not less than ordinary hazard. Light hazard is below that minimum and is the common wrong answer.
Where they go:
- At each stairway on all floor levels where combustible materials have accumulated. If combustibles sit only on floors 2 and 4, the stairways on floors 2 and 4 need them, not every floor.
- In every storage and construction shed, both kinds.
- Additional units where special hazards exist, such as flammable or combustible liquids. Liquids trigger extra units; they are not the only trigger.
Roofing operations, IFC 2021
On a roof being covered or repaired, the IFC roofing rule (3318.3 in the Houston numbering) requires not fewer than one multiple-purpose extinguisher with a minimum 3-A 40-B:C rating on that roof. The trap is 2-A 10-B:C, a misremembered lower rating.
Fire watch, IBC 2021 3314.1
A fire watch is required during nonworking hours in any of three independent cases:
- Construction exceeds 40 ft above the lowest adjacent grade at any point along the building perimeter.
- New multistory construction with an aggregate area exceeding 50,000 sq ft per story.
- As required by the fire code official.
A 30 ft warehouse with 60,000 sq ft per story needs a fire watch on the area trigger alone. Being under 40 ft does not end the analysis.
Two reference points
The fire watch measures from the lowest adjacent grade. The stairway in 3310.1 measures from the lowest level of fire department vehicle access. On a hillside building 44 ft above grade at the downhill wall but 34 ft above the uphill access street, the fire watch applies (44 exceeds 40) and the stairway does not yet (34 does not). Swapping the reference points is the trap.