What You Need To Know About Foam And NFPA 1901 Standard

It’s likely you’ve heard the new 2009 National Fire Protection Association 1901 apparatus standard took effect in January. There are a number of significant changes apparatus builders make aware of to ensure compliance. One is a section that sets new requirements for the testing and calibration of foam systems.

NFPA standards are voluntary, but always viewed as the minimum safety level in court. You can certainly choose to specify a higher standard for your apparatus, but understand that if you fail to prove compliance, you could be putting your company or your department at risk.

NFPA standards have been developed over time, usually as the result of something undesirable happening, an injury or a line of duty death. So pay attention to the standards. They could save the company reputation or even save a life.

The current edition of the NFPA 1901 standard details new testing and certification requirements for the foam system manufacturer, installer and purchaser.

The purchaser, according to the standard, shall specify the following: range of waterflows and pressures; proportioning rates; types of concentrates; and brand and viscosity of concentrates.

This information is required so the installer knows how the purchaser plans to use the system and what water additives are expected to be used. All this is vitally important so the installer can provide the purchaser with a foam proportioning system that will meet a department’s needs and do the job expected.

If the purchaser does not specify a range of waterflows and pressures, the installer may wrongly assume the department only plans to operate at a single flow rate and pressure and install a proportioner with a very narrow operating range. With proper specifications however, the installer would know that the purchaser really intended to operate a single handline at 25 gpm for overhaul and up to several lines for blitz attacks with the capability to use either a Class A and Class B concentrate.

At the same time, the purchaser needs to be realistic. Every proportioning system has its own capabilities and limitations. No one system can do it all. Time should be taken to think through what is needed in a proportioning system and how it will be used

Company Responsibilities

The specs that are generated are what the installer will use to select a proportioning system that will meet the department’s requirements. The foam proportioning system manufacturer is required to test and certify the capabilities of each system sold. This data ensures the system performs as the manufacturer claims. So let’s look at what information the manufacturer must provide.

Section 20.10.1 of NFPA 1901 says: “The foam proportioning system shall be type tested and certified by the foam proportioning system manufacturer to be accurate throughout the foam proportioning system’s declared range of water flow, water pressure, foam percentage (or foam proportioning system capacity), and concentrate viscosity.”

It is not enough that the foam proportioning system be able to perform over the advertised range of water flows and water pressures. The 1901 standard specifically defines the level of accuracy the proportioner must maintain over its entire performance range.

Rich Rather Than Lean

The standard allows the foam proportioning system to operate slightly on the rich side if it cannot precisely hit the desired proportioning rate. Under no circumstances is the system permitted to operate lean. The reasoning behind this requirement relates to Class B concentrates, which must pass a UL test. A concentrate designed for use at three percent is UL tested at three percent and if it passes, it is allowed to go to market.

Purchasers of that concentrate expect it to perform on the fuels it was designed for and effectively extinguish those fires and provide burnback protection when using that concentrate. What happens if instead of proportioning that concentrate at 3 percent, we run a little lean and it gets proportioned at 2.5 percent? Well, with a good concentrate that easily passed the UL test, maybe nothing.

However, you may someday find yourself in a situation where a vehicle’s fuel tank has ruptured and subsequently ignited. You now have to extinguish it and rescue victims in the vehicle. This is not the time to find out that the concentrate you are using was only marginal when it passed the UL test and does not provide burnback protection when proportioned at only 2.5 percent. This is why NFPA allows proportioners to run rich, but not lean.

Reasons For Accuracy

While the standard does allow the proportioning system to operate on the rich side, there are a number of reasons why you want as accurate a system as possible. First, you are usually operating with a finite supply of concentrate. You do not want to waste foam and run out before the fire is extinguished. Second, foam costs money. In an era of tight budgets, we can hardly afford to waste expensive foam. Third, we do not want to put any more chemicals on the ground than are necessary.

So far, we know what the purchaser is looking for because fire department officials took the time to review their needs and write them in their specification. Next, the manufacturer of the foam proportioning system designed and tested a system that will meet the specs of the purchaser.

Does this ensure that the fire department will get what it wants? Not necessarily.

If the system is not installed properly or not calibrated correctly, it likely will not perform to its capabilities and may fail prematurely. The new NFPA 1901 standard takes that possibility out of the equation by requiring the installer to test and certify the installation of the foam proportioning system.

Provided the purchaser, manufacturer and installer have all fulfilled their respective requirements, the foam proportioning system will now perform as it was designed, reliably meeting the expectations of the purchaser for many years to come.

That is precisely what the changes to NFPA 1901 were intended to provide.

Anyone who has a question about the standard may submit a request for a formal interpretation to the NFPA. The request must be worded in such a manner that it can be answered “Yes” or “No.” Requests can be made through the NFPA Web site at www.nfpa.org.

Editor’s Note: Bill Ballanyne is vice president of the FoamPro Division of Hypro Corporation and has been active in the fire service for more than 12 years. He is a past president of the Fire Apparatus Manufacturers Association (FAMA) and is a member of the National Fire Protection Association’s 1901 Fire Apparatus Standards Committee.

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