NFPA Maintenance Issues for Water Storage Tank Inspections & Heating
Volume 22, No. 6
Your sprinkler system is one of your most valuable assets at your facility. If one component of that system fails during a fire, your facility is financially impacted. And the most important component needs to be maintained - your water storage tank.
The National Fire Protection Association (NFPA) has guidelines in place to ensure your tank is kept at its most optimal level of operation. We are going to explore two very important issues, which during the rush of other daily tasks are sometimes overlooked. One is routine inspections and the other is tank heating.
Let's start with inspections. According to NFPA-25, all components unique to your system are to be inspected and tested at the required times and necessary maintenance provided by a qualified contractor or qualified owner's representative. It goes further to say in Chapter 9 that the interior of steel tanks without corrosion protection are to be inspected every three years and subsequently the interior of other types of tanks to be inspected every five years. In addition, the NFPA also refers to the AWWA M42 publication as a further source of information on the inspection and maintenance of steel tanks.
There are generally two options for inspection - dry and ROV (Remote Operated Vehicle). Dry is just as it sounds. All water is removed from the tank and qualified inspection personnel enter the tank to conduct the internal inspection in accordance with NFPA. Depending on the source of your water, this method may require the loss of purchased water and an expense associated with re-filling the tank. Therefore an ROV option, which does not require the draining of the tank nor the lockout/tag-out procedures associated with divers, fully meets NFPA inspection requirements with a better solution.
The ROV is controlled by qualified inspection personnel trained to use this equipment. By this method you or your representative can view the inspection via monitor and speak directly with the inspection personnel. Just as with the dry inspection, all aspects of your tank are inspected - structural, safety and coating con-dition. With either method, a written detailed report of findings with photographs, corrective recommend-ations and cost estimates should be provided to you. The ROV method often includes a DVD. Incident-ally, in the event your tank has duel purposes (fire and potable) you should make sure all submersible equip-ment is fully disinfected before being placed into the tank.
Concerning heating, NFPA-25 Chapter 13 says that all tanks subject to freezing (based on the isothermal map) be heated and maintained at or above 42 degrees during the coldest weather. There are various heat systems that can be utilized to meet this requirement. However, insulating the exterior of the tank can be the most cost effective application. After the installation costs of the material, this application begins to pay for itself. Unlike other systems, this application does not require steam, electricity, coal, oil or gas.
An application of R-10 insulation can maintain your stored water temperature at a minimum of 42 degrees while realizing an annual savings in energy costs! Just as a back-up measure, one or two electric immersion heaters can be installed inside the tank. Generally, these never kick on. Depending on current heating method your capital investment of heating equipment can be reduced by 80 percent with typical payback of 1? to two years based on local utility rates.?????????????????????
Danette D. Sutton is in the Maintenance Sales Division of Pittsburg Tank & Tower Co., Inc. Pittsburg Tank & Tower Co., Inc. is a well established company in the tank industry who provides services for fire protection and potable steel storage tanks in the public and private sector. Pittsburg Tank & Tower performs inspections using "Odyssey" 1 & 2 ROV units and insulation installations. The company can perform one-time services or develop custom routine maintenance packages.
For more information contact: Pittsburg Tank & Tower Co., Inc., PO Box 913, Henderson, KY 42419; (270) 826-9000 Ext. 228, Fax (270) 827-4417, Email: email@example.com, Website: www.watertank.com