Highland HighDRO® Fire Protection Tanks to the Rescue!

Water supply is one of the most critical elements of firefighting with demand sometimes exceeding the available supply. Water tanks to supplement available domestic water supplies are an integral part of a well-planned fire-protection system. They provide peace-of-mind, especially during drought conditions, infrastructure failure, loss of pumping capacity and heavy demand during extensive firefighting.

Fire protection systems have two primary functions, life safety and property protection. A properly designed water storage system is an important component of any water distribution system with the tanks being a critical element in the system’s capability.

Highland Tank’s HighDRO® Fire Protection Tanks (FPT) are an integral part of fire protection systems all over the country.

HighDRO® FPTs provide water for fire pumps in automatic fire sprinkler, wet riser or mist systems at schools, hospitals, prisons, housing developments, warehouses, aircraft hangars, industrial plants, resorts and many other facilities that need a reliable and redundant water supply.

Water tanks are a requirement of NFPA® 22 Standard for Water Tanks for Private Fire Protection in many residential, commercial, industrial and institutional buildings for use with fire suppression sprinkler systems. Fire codes such as the International Fire Code call for stand-alone, standby water supplies.

Single-wall construction is the standard for atmospheric tanks in fire protection systems. Design and construction are governed by standards such as the NFPA® 22 and American Water Works Association AWWA D100 Standard for Welded Steel Tanks for Water Storage.

Single-wall construction employs a single layer of steel meeting ASTM standards with material thicknesses ranging from 12-gauge to 1-1/4”. Flat-flanged or dished heads, continuous exterior and interior welds, on all joints and a verifiable 5-psi factory air test ensures a safe and secure storage tank. All Highland Tank FPTs are custom fabricated ensuring all the correct fittings are included for each specific application. Components such as single or Siamese dry hydrants with anti-vortex plate (for suction systems) fill ports and level indicators.

Types of Prefabricated Steel Storage Tanks For Water Supply

FPTS are available in multiple designs and water delivery methods. Atmospheric FPTs provide water via gravity flow or pumped discharge. Some fire protection applications need the water to be supplied under pressure, requiring an ASME pressure vessel. Cistern tanks may be required in suburban or rural areas served by a well with limited delivery capability.

A secondary, on-site water supply, equal to the sprinkler and hose stream demand over a prescribed time period may be required by code for some building applications resulting in the need for large volume storage tanks. In some instances, multiple, interconnecting tanks may be required to satisfy water demand.

Steel FPTs take on multiple shapes – cylindrical horizontal or vertical and rectangular, provided they conform to all requirements of this NFPA® 22 and the requirements of the Authority Having Jurisdiction. Highland Tank specializes in fabricating custom sizes and configurations of tanks for fire protection systems.

Always contact your local fire and building officials regarding volume and configuration, before moving ahead with a storage tank project involving firefighting systems.

Welded-Steel Gravity Tanks

Gravity tanks were some of the earliest tanks employed in fire protection because they do not require a mechanical means to provide pressure. Elevation and gravity provide the needed pressure. They can be installed at elevated heights in a building or on a nearby hill. Typically, one foot of elevation will provide approximately 0.433 psi, and a column of water 2.31 ft. high will produce 1 psi at the base of the column.

HighDRO® Welded-Steel Gravity Tanks are commonly installed at large commercial facilities like warehouses.

Welded-steel gravity tanks, like most aboveground vertical or horizontal storage tanks, must meet the requirements for resistance to loads such as: water weight, wind, earthquake and lightning protection. Always consult proper authorities and regulations before installing tanks in elevated locations.

ASME Pressure Vessels

ASME pressure vessels are manufactured for many fire suppression sprinkler systems. During normal operation, these hydropneumatic vessels are filled to the two-thirds level with water. Air pressure is then applied to the remaining one-third to provide the needed pressure. The air pressure is sufficient enough to displace the water at the necessary pressure required for the sprinkler piping system.

Highland Tank fire protection vessel construction complies with the ASME Code, Section VIII, and Division I. They are welded in accordance with ASME Section IX and are subject to jurisdictional pressure vessel inspections just as boilers and other pressure vessels.

High-rise buildings use HighDRO® Rectangular Gravity Tanks for custom fit and size, to provide sufficient water pressure to reach the fire-fighting systems on top floors.

Welded Steel Suction Tanks

Aboveground and underground suction tanks are becoming more popular as a stored water source. Fire pumps are usually housed in a pump room close to and at a level just below the bottom of the suction tank. They provide positive head pressure via gravity flow on the fire pump so the pump need not draft from the tank. When installed underground, a suction tank with a bottom drain is connected to either a vertical pump wet well or sub-grade fire pump suction. Both styles of fire protection tanks maintain a secure dedicated water supply for a building’s overhead fire sprinkler or fire hoses.

Pressure Vessels for fire protection are typically 2/3 full of water, then pressurized with air to provide the required firefighting capability. They are designed to National Fire Protection Association’s NFPA 22 code with factory applied internal and external coatings.

Highland Tank One Highland Road • Stoystown, PA 15563Phone: 814-893-5701 • Contact: Emilie Lynch Email: marketing@highlandtank.com

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Underground Cisterns

Cisterns are atmospheric water tanks with properly sized air vents extending above grade to allow free flow of air during their filling and draining (firefighting) cycles.

When installed under ground, these tanks provide unseen protection for the building occupants and are easily accessible for fire and municipal vehicles. Depending on the need, they can store ten times the volume of a fire tanker. They are common in rural areas, especially where drilled wells do not have sufficient water flow to sustain the fire-fighting flow rate. NFPA has published guidelines regarding the location and volume of an appropriate fire cistern based on the structure(s) it is designed to protect.