The One-Page Sprinkler Letter

Both, and the design problem is the serious one.

The 2014 system was calculated around a specific set of conditions: storage height, rack type, aisle width, and commodity. The tenant changed at least four of those. An ESFR design is sensitive to storage height and to whether shelving is open or solid, because solid shelves alter how the ceiling spray reaches the commodity. Extending storage by 6 feet can push the arrangement outside the design tables entirely, and the applicable deflector-to-storage clearance for the specific listing must be verified - the standard 18-inch figure is not automatically the ESFR number, and assuming it is how buildings burn.

Before occupancy:

• A permit and a full submittal with new hydraulic calculations, commodity classification, rack detail, and the listing basis for the ESFR heads at the new storage height.
• Plan review and approval by the code official, not by the installing contractor.
• Acceptance testing and documentation of the modified system.
• Restoration of the control valve and confirmation via main drain and alarm test.

A contractor's assurance letter carries no weight. The code official accepts installations, not correspondence.

Closed valve. An unsprinklered warehouse of this size with 31-foot combustible storage is an active impairment. Require the impairment procedure: an impairment coordinator, notification to the fire department, a documented fire watch in the affected area for the duration, tags on the valve, and restoration testing before the watch is withdrawn. The fact that it was 'quick' is irrelevant; the risk exists for the whole period the valve is shut.

Painted heads. Painted sprinklers are defective and must be replaced, not cleaned. Paint on the thermally sensitive element alters activation, and no manufacturer lists a painted head. Twelve heads means twelve replacements plus an inspection of the remainder of the system for the same practice - if the painter did it in the visible area, check the back of the racks too.

Neither item can be closed administratively. Issue the notice of violation, record the impairment start and end times, and do not approve occupancy until the valve is restored, the main drain and waterflow alarm are tested, and the replacement heads are documented.

Aisle width in a racked warehouse is not a comfort metric; it is part of the design basis. Widening one aisle can be irrelevant or harmful depending on which aisle the calculations used, and narrowing or blocking another removes the access the fire department and the sprinkler design rely on.

• Compare the installed layout to the approved plan, not to a general impression of what feels wide enough. If the approved plan shows a different arrangement, the installed arrangement is a deviation requiring review.
• Pallet storage in an aisle is obstructed access, whether or not it is labeled temporary. 'Temporary' is not a code category; the condition is either corrected at the time of inspection or cited with a compliance date.
• Verify the aisle against the high-piled storage requirements as well as the exit access path. An aisle being used for storage may be the only clear path to an exit or to a fire department access door.

Write the finding as a deviation from the approved submittal with measurements and photographs. Handle the storage-height and sprinkler-clearance issues first, since the aisle argument becomes moot if the system must be redesigned anyway.