Fire Hydrants | UL ULC FM AWWA C502 Dry-Barrel Wet-Barrel | Valve-Atlas

Fire Hydrants: UL, ULC, FM and AWWA Listed Supply

ValveAtlas supplies UL Listed, ULC Listed, FM Approved and AWWA C502/C503 compliant wet-barrel and dry-barrel fire hydrants for municipal fire flow, private water main hydrants, fire pump test header outlets and FDNY/FDN-Toronto compliant public way service on projects in Toronto, Montreal, New York, Boston and London.

This page is the technical reference for municipal engineering firms, EPC firms, utility contractors and fire service commissioners specifying fire hydrants on underground water main systems governed by NFPA 24 Chapter 7, NFPA 25 Chapter 7, AWWA C502 (dry-barrel) and C503 (wet-barrel), BS EN 14339 (UK above-ground hydrants), Approved Document B and OBC Part 3.

Hydrant range at ValveAtlas

Type	Construction	End connection	Listings	Outlets	Typical AWWA class
Dry-barrel traffic-model hydrant	Cast iron body, bronze internals, compression-type main valve	6″ MJ inlet	UL, ULC, FM, AWWA C502	Two 2½” NST hose + one 4″ or 4½” pumper	Class 150 or Class 250
Wet-barrel California-style hydrant	Bronze body for frost-free regions only	6″ MJ inlet	UL, FM, AWWA C503	Two or three 2½” NST hose + pumper	Class 175
Monitor nozzle hydrant	Cast iron with 4″ or 6″ monitor outlet for industrial firewater	6″ MJ inlet	UL, FM	Monitor nozzle plus 2½” hose outlets	Industrial class

Dry-barrel vs wet-barrel selection

Dry-barrel (freeze-protected). Toronto, Montreal, Boston, New York. The main valve sits below the frost line at the base of the hydrant. When closed, the barrel drains through a small weep hole at the base into the surrounding soil, leaving the above-grade portion empty and freeze-proof. Required in all cold-climate cities per AWWA C502 and local municipal standards.

Wet-barrel (freeze-free regions only). California, Florida, frost-free UK coast. The main valve is at the barrel top; water fills the barrel to the outlets. Faster response (no main valve delay) but cannot be used where ground freezes. London UK may use wet-barrel on inner-city high-water-table installations where freeze risk is very low.

Monitor hydrants. Industrial sites (refineries, chemical plants, power stations) requiring large-volume elevated fire streams. Combines standard pumper and hose outlets with a 4″ or 6″ monitor nozzle for long-range industrial firewater service.

Listings and code acceptance

UL 246. Fire hydrants for UL Listed public-way service. UL certificate provided in the ValveAtlas submittal package.

FM Approvals Class 1310. FM-insured property fire hydrants. FM Global, RSA, Aviva, Zurich, Allianz, AXA Commercial and Chubb surveyors accept FM certificate on their insured properties.

ULC listing for Canadian projects. Canadian installations use ULC-listed hydrants accepted under CAN/ULC-S543. Toronto Fire Services, Toronto Water and Montreal’s Service de sécurité incendie accept ULC certificates.

AWWA C502 dry-barrel. AWWA Manual M-17 covers dry-barrel hydrant installation and testing. Every AWWA C502 hydrant ships with certified hydrostatic test records.

BS EN 14339 UK standards. Above-ground hydrants in the UK follow BS EN 14339 for Type 2 and Type 3 hydrants. Fire and Rescue Service acceptance per UK building regulations Approved Document B.

Hydrant accessories and trim

Breakaway safety flange. AWWA C502 hydrants include a breakaway flange at grade designed to shear on vehicular impact, protecting the buried valve and underground piping from damage. Replacement breakaway flanges stock at Toronto HQ.

Operating nut and wrench. Standard pentagonal operating nut (1½ inch point-to-flat) coordinated with municipal fire department wrenches. FDNY uses a 1¼ inch pentagonal nut on NYC hydrants; verify with the local fire department before ordering.

Hose and pumper outlets. Standard 2½ inch NST (National Standard Thread) hose outlets and 4 inch or 4½ inch pumper outlets. NYC Local Law 27 requires 4½ inch pumper outlet for FDNY service. Verify local thread standard with the fire department; UK hydrants use BS 336 Type A instantaneous couplings.

Valve box and cover. Cast iron adjustable valve box and traffic-rated cover for buried isolation valve on the hydrant tee per AWWA M-17.

Extension sections. Dry-barrel hydrants are supplied with extension sections (6 inch, 12 inch, 18 inch, 24 inch extensions) to match site grade. Order extensions based on finish-grade elevation from the hydrant shoe.

Substitution matrix from Mueller, Clow, Kennedy, AVK

Mueller Super Centurion 250. Substitute UL/ULC/FM listed dry-barrel hydrant. Same AWWA C502 scope, compression-type main valve, compatible operating nut.

Clow Medallion. Substitute UL/ULC/FM listed dry-barrel. Same scope.

Kennedy K-81A dry-barrel hydrant. Substitute UL/ULC/FM listed dry-barrel with breakaway flange.

AVK Series 27 UK hydrant. Substitute BS EN 14339 compliant UK hydrant for London and UK installations.

Regional stock and delivery for fire hydrants

Toronto. Dry-barrel hydrants in stock at Toronto HQ with AWWA C502 certification for Ontario municipal installations. Toronto Water and GTA municipality specifications supported.

Montreal. Next-day truck freight. Ville de Montréal and Service de sécurité incendie de Montréal acceptance. French-language certification package.

New York. 2-day truck freight from Toronto. FDNY and NYC DDC specifications for public way service; 4½ inch pumper outlet standard.

Boston. 2-day truck freight. BWSC (Boston Water and Sewer Commission) and BFD acceptance.

London UK. UK partner warehouse stock BS EN 14339 compliant above-ground hydrants. 5 to 7 day air freight on specialty monitor configurations.

Related products for complete underground water main

Gate valves. UV0299 NRS gate in the hydrant tee vault for hydrant isolation. See Gate Valves.

Post indicator valves. UV0800-IP PIV for isolation of sprinkler system feeds (separate from hydrant service).

Fittings and couplings. Mechanical joint (MJ) fittings, ductile iron ells and tees, and restrained couplings on the underground water main. See Coupling Fittings.

Check valves and detector check valves. Listed swing check and detector check on the building water service entry from the public main.

Frequently asked questions

What spacing is required between hydrants? NFPA 1 Section 18.5 and IFC Section 507 require hydrant spacing based on the required fire flow: typical spacing is 300 feet in commercial areas and 500 feet in residential. Minimum distance from a protected building is 40 feet; maximum distance is 400 feet for commercial (reduced from max spacing for fully sprinklered buildings).

What fire flow can a hydrant deliver? Standard AWWA C502 hydrant delivers 1000 to 1500 gpm through a single 4½ inch pumper outlet at 20 psi residual pressure when connected to a 6 inch main at 60 psi static. Larger-flow applications (commercial/industrial) use 1500 to 3000 gpm hydrants with larger barrel and seat diameters. Verify fire flow availability against NFPA 291 flow test requirements.

How is a hydrant tested annually? NFPA 25 Chapter 7 requires annual hydrant flow test: flush each hydrant at full flow until water runs clear, record static pressure, flowing pressure and pitot gauge reading at the pumper outlet. Annual maintenance also covers greasing the operating nut and stem.

Can a hydrant be used for non-fire purposes? Private hydrants on industrial sites may be used for wash-down, dust suppression or process water. Public way hydrants are restricted to fire service; unauthorized use (filling water tanks, construction dewatering) requires a permit from the water utility.

What breakaway flange does the hydrant use? Standard AWWA C502 breakaway flange at grade uses brittle bronze bolts that shear on 2000 pound impact load. After impact, the hydrant separates cleanly at the flange; the underground valve remains closed and protected. Replacement bolt kits stock at Toronto HQ.

Contact ValveAtlas for a fire hydrant quotation

For fire hydrant quotations, underground water main submittals, monitor hydrant configurations or UK BS EN 14339 submittals on Toronto, Montreal, New York, Boston or London projects, email the project specification and drawings to burakpadr@gmail.com or use the contact form. Standard turnaround is 48 hours.