AR Fire Sprinkler cheat sheet

NFPA 13 governs design and installation of commercial sprinkler systems; NFPA 13R covers residential occupancies up to four stories, and NFPA 13D covers one- and two-family dwellings.

Light hazard design density is typically 0.10 gpm/ft² over 1,500 ft²; Ordinary Hazard Group 1 is 0.15 gpm/ft² over 1,500 ft², and Ordinary Hazard Group 2 is 0.20 gpm/ft² over 1,500 ft².

Design area may be reduced for dry systems (by 30%), for sloped ceilings, and for use of quick-response sprinklers in wet systems, but the reduction is capped and never below 1,500 ft².

Maximum sprinkler spacing for light hazard is 15 ft between sprinklers and 225 ft² per sprinkler; ordinary hazard allows up to 130 ft² per sprinkler at 15 ft spacing.

Sprinklers must be positioned so deflection does not exceed 12 in. below the ceiling for standard spray sprinklers, with higher limits permitted for specific ceiling types.

A 1 in. main drain and a flow test are required at the remote point; system demand must not exceed available water supply at the point of connection.

Hydraulic calculations must use the Hazen-Williams formula with C=120 for steel pipe (wet systems) and C=100 for dry systems, unless other listed values apply.

Sprinkler systems must be hydrostatically tested at 200 psi for 2 hours (or 50 psi above working pressure if it exceeds 150 psi).

The Arkansas Fire Protection Licensing Board regulates sprinkler system contractors and installers under Arkansas Code Title 20, Chapter 22.

A firm must hold a valid fire sprinkler contractor license and employ at least one licensed responsible managing employee to legally contract for sprinkler work.

Individual installers must be licensed; apprentice or helper registration is required for those working under a licensed installer.

Licenses must be renewed on the Board's renewal cycle, and continuing education or fees may be required to maintain active status.

Contractors must provide proof of insurance, including general liability, as a condition of licensure and renewal.

Unlicensed practice or contracting without a license is subject to civil penalties and possible criminal sanctions under state statute.

Plans and specifications for sprinkler installations are typically required to be submitted to the local authority having jurisdiction, which may also require Board-licensed contractor identification.

Licensee records, including contracts and installation documentation, must be maintained and made available to the Board upon request.

Wet-pipe systems are the standard for heated occupancies; dry-pipe systems are used where freezing is possible and require a dry pipe valve and air pressure.

A dry pipe valve must have a quick-opening device or be sized so that water delivery occurs within 60 seconds of the farthest sprinkler opening.

Check valves, OS&Y gate valves, and indicating control valves must be provided at the riser and at connections to water supplies.

Sprinkler temperature ratings must be at least 20°F above the maximum expected ambient ceiling temperature.

Water supply sources include public mains, gravity tanks, suction tanks, and fire pumps; each must be capable of supplying the calculated demand plus hose stream allowance.

A fire pump must be sized so the pump curve provides at least the required system demand at the design point, and a bypass is required around the pump.

Hazen-Williams head loss: p (psi) = 4.52 × Q^1.85 / (C^1.85 × d^4.87) per foot of pipe, with Q in gpm and d in inches.

A backflow preventer is required where the sprinkler system connects to a potable water supply, and its friction loss must be included in the hydraulic calculation.

NFPA 25 establishes the minimum inspection, testing, and maintenance requirements for water-based fire protection systems after installation.

Gauges on wet systems must be inspected monthly; main drain flow tests are performed quarterly, and waterflow alarm tests are performed quarterly.

Dry pipe valves and preaction valves require annual trip testing; dry pipe systems must have their air pressure and priming water checked monthly.

Sprinkler heads must be inspected annually for corrosion, paint, and damage; heads that have operated or are more than 50 years old in certain conditions must be replaced or tested.

Internal pipe inspection is required every 5 years for dry systems and every 5 years for wet systems where conditions warrant.

The main drain test compares static and residual pressure to detect supply degradation; a significant drop from baseline indicates a supply or valve problem.

Records of all inspections, tests, and maintenance must be retained and made available to the AHJ; NFPA 25 requires a written record for each activity.

Impairment procedures require notification of the AHJ and building owner, a fire watch if the system is out of service, and documentation of the impairment.

A written contract should define scope, applicable codes, schedule, payment terms, and responsibility for permits and inspections.

Change orders must be documented in writing before additional work proceeds to preserve the contractor's right to payment.

Jobsite safety includes controlling hot work with a permit, maintaining fire watch, and following OSHA fall protection and lockout/tagout requirements.

Lien rights in Arkansas generally require timely notice and filing; contractors should track statutory deadlines for mechanics' liens.

Insurance coverage should include general liability, workers' compensation, and completed operations coverage for sprinkler installations.

Toolbox talks and documented safety training reduce liability and support compliance with OSHA and project-specific safety plans.

Bid estimates should account for material takeoff, labor hours, equipment, permits, overhead, and profit margin, with a contingency for site conditions.

Retain project records, as-built drawings, and test reports for the period required by contract and statute to defend against claims.