Articles

by Kayla Kuhlman

NFPA and other recognized standards recommend the testing of low expansion concentrate be done annually to ensure that the integrity of the foam is holding up over time.  A failing result on a Dyne Fire Protection Labs test report may lead to an investigation to either replace the foam concentrate or equipment, which can cost money and time. 

It is important to understand the reasons why your firefighting foam concentrate may be failing as various factors can contribute to a sample failing.  Additionally, this knowledge may be helpful when sending samples in for testing.  Common causes of a foam sample failing include incorrect product information, dilution, aging, improper storage conditions, mixing incompatible foam, and improper sampling technique.

by Grant Lobdell

When a sprinkler does not perform as expected, it is easy to assume the issue is caused by a manufacturer defect.  However, listed sprinklers in the United States, as required by NFPA 13 (Section 6.1.1.2 in the 2016 Edition), go through a wide variety of strict testing protocols at Underwriters Laboratory (UL) and/or Factory Mutual (FM) Approvals to greatly reduce this occurrence.  It is therefore generally far more likely that the sprinkler failure is due to something that occurred after the manufacturing process.

Sprinkler mishaps caused by physical contact (coat hanger resting on a sidewall sprinkler, forklift hitting a pendant sprinkler, etc.) can be easily explained.   However, when the mishap happens without this physical contact, it can be quite a mystery as to why.  Below is a list of the more common mysterious sprinkler mishaps with possible causes explained.

Issue: A sprinkler activated despite there being no fire.

Possible Cause: The sprinkler was stored in a high temperature environment.

Explanation: When a sprinkler is exposed to a temperature close to but not at its activation temperature, it can weaken the thermal element.  Solder release mechanism sprinklers in particular can experience what is called solder migration, which is caused when high storage temperatures soften the solder so it becomes slightly malleable but not enough to release.  When the storage temperature lowers and the sprinkler cools, the solder hardens in its new position (it has drifted) and is slightly weaker than it originally was, thus lowering the actual activation temperature.  Eventually, the sprinkler’s activation temperature is low enough where it will release in ambient conditions.  For this reason, NFPA 13 and NFPA 25 both outline maximum ceiling temperatures for various sprinkler types (Sections 6.2.9.3 of the 2016 Edition and Section 5.4.1.5.2 of the 2017 Edition, respectively).  This is also why NFPA 25 requires solder-type sprinklers with a temperature classification of extra high or greater that are exposed to continuous maximum allowable ambient temperature conditions to be tested every 5 years according to Section 5.3.1.1.1.4 and A.5.3.1.1.1.4 of the 2017 Edition.  Be sure the sprinkler you have installed is the proper sprinkler for your environment and ensure any possible high temperature fluctuations are accounted for.  Care should also be taken when storing stock sprinklers in sprinkler cabinets or before installation.

Issue: A sprinkler is leaking water despite not being activated.

Possible Cause:  The water seal seat was disturbed due to overtightening during installation.

Explanation:  Sprinklers sold today in the United States should come with a technical datasheet on the product which will outline torque requirements.  If these requirements are not followed and the sprinkler is installed with excess force, the torque can distort the seat between the frame and the water seal.  Note that sometimes the leak can be very minor, only causing an excess of corrosion around the water seal specifically.  Should this occur, replacement of the sprinkler will be required according to the 2017 Edition of NFPA 25 Section 5.2.1.1.1.

Issue: The frame of a sprinkler cracked and/or broke despite no one touching it.

Possible Cause: The water line behind the sprinkler froze.

Explanation: Generally, this occurs with glass bulb sprinklers.  To better understand how this occurs, you need to understand that the glass bulb is generally stronger (longitudinally) than the metal frame.  Therefore, when the water line freezes behind a sprinkler and pressure builds up, the first thing to break will not be the glass bulb.  Instead the sprinkler frame will give way and crack or sometimes separate completely.  If this occurs, freeze protection measures may need to be investigated.  The sprinkler should also be replaced according to the 2017 Edition of NFPA 25 Section 5.2.1.1.1.

Issue: The fluid color in the glass bulb of a sprinkler faded.

Possible Cause:  The sprinkler was in a cold environment or in direct sunlight.

Explanation:  The fluid in a glass bulb sprinkler is generally an alcohol dyed to identify its classification.  This dye can lose its color from UV light, generally from the sun; but it has also been found in some cases to lose color due to cold temperatures (sometimes even regaining its color when the sprinkler is placed into a warm environment again).  It should be noted that the liquid inside a glass bulb can actually be the same across all classification.  The only differences are the dye and the size of an air bubble that is placed inside the tube.  The air bubble size is actually what gives rise to the varying activation temperatures and not the dye or liquid.  Therefore, the dye plays no part in performance and a sprinkler that has experienced fluid color change can still be left in service according to NFPA 25 (Section A.5.2.1.1.1 of the 2017 Edition).  In extreme cases of the dye fading where it appears clear, it can be hard to tell if the sprinkler has lost its fluid or if that fluid has just changed colors.  To determine this, you will want to identify if that air bubble is still present in the bulb (and roughly the same size as it was).  If it is present, the liquid is still there.  If not, the fluid has escaped and the sprinkler will need to be replaced according to the 2017 Edition of NFPA 25 Section 5.2.1.1.1.

Issue: The fluid in the glass bulb of a sprinkler disappeared.

Possible Cause: The fluid leaked out of microscopic cracks in the glass caused by sprinkler mishandling during pre-installation.

Explanation:  While the glass bulb is quite strong longitudinally, it is quite fragile in many other ways.  The fluid inside can expand and put pressure on the glass to break it.  You can simply apply a latitudinal force to it as well.  Sometimes the glass can be weakened without fully or visibly breaking.  Microscopic cracks in the glass, which cannot be spotted with the naked eye, can occur in a glass bulb that has been mishandled prior to installation.  This can result from the sprinklers being dropped, for example (note that the manufacturer puts great care into sprinkler packaging to avoid this).  While the microscopic cracks aren’t enough to see a loss of fluid immediately, they can leak very slowly over time.  Sometimes you will notice coloration around the sprinkler that matches that of the fluid that is/was in the glass bulb.  Sprinklers that have experienced fluid loss need to be replaced according to the 2017 Edition of NFPA 25 Section 5.2.1.1.1 as the activation temperature would be greatly affected.

by Evelyn Vogel

What is the difference between foam concentrate and foam solution or shell water and system water? To receive the most accurate and timely testing results, Dyne must know what type of foam or water is inside each sample bottle. Figure 1 shows part of the Dyne Foam and Antifreeze form. For easier use, this part of the form was recently reformatted. The concentrations are now split into non-alcohol resistant foam options and alcohol resistant (AR) foam options.

by Erin Van Ruiswyk

Since the first automatic fire sprinkler system was patented in 1872, almost 150 years have passed along with countless developments to these sprinkler systems. Fire protection today uses a variety of sprinkler systems for different applications – primarily wet, dry, and preaction systems. The evolution of the individual sprinklers has also seen some pretty dramatic progress.

One very important development in fire sprinkler history came in the 1930s, when the dry sprinkler was introduced. Dry sprinklers are designed to be used in environments that are subjected to freezing temperatures. They operate similarly to standard sprinklers, but they include a sealed extension nipple (see Figure 1). Since the seal that keeps out water is at the end of the extension, the entire barrel is kept dry until the sprinkler operates, so that no freezing will occur in the sprinkler that could prevent proper operation.

When you think of a fire sprinkler failing the periodical testing as required by NFPA 25 and performed by Dyne Fire Protection Labs, you may assume it is because the glass bulb or soldered release mechanism didn’t activate in time or at all.  However, that can be quite rare especially in the case of a glass bulb.  The actual number one cause of a failure for a sprinkler tested here at Dyne is due to the water seal not releasing as intended.  After being exposed to a specified flow and temperature, the release mechanism has activated just fine but the water seal still remains attached to the sprinkler.  What causes this to happen?  By far the top reason is because of corrosion.  Corrosion, both external and internal, can fuse a water seal to the frame.  This is why NFPA 25 also states that during your floor level inspection, you are to replace any sprinkler that shows signs of corrosion that is detrimental to performance.  Other articles and videos by Dyne in the past have given examples of when corrosion is detrimental to assist in making this very difficult judgment call.  However, we haven’t discussed what causes that corrosion and if there are ways to prevent it – until now.  Let’s break it down into external and internal corrosion.

The 2017 Edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems states in 5.2.1.1.1 that “any sprinkler that shows signs of loading and/or corrosion detrimental to the sprinkler performance shall be replaced”.  By simply looking at the sprinkler, it can be difficult to know when loading and/or corrosion is detrimental to the performance. To help those in the field make this call, this document has been put together with some real-life examples of loaded and/or corroded sprinklers that have response times outside the acceptable range.  Generally, loading will increase response time due to its insulating effect on the release mechanism whereas corrosion will hold the water seal or release mechanism together longer than desired or, in some cases, prevent release entirely. 

Ensuring a representative sample of firefighting foam is taken and sent to Dyne Fire Protection Labs is essential in ensuring safety, quick and accurate results, and limiting future retesting expenses.

COLLECTING A SAMPLE THROUGH A PIPE

Whenever a sample is taken directly from piping, be sure to run some foam through the lines before collecting.  The foam stored in pipes can contain contamination as well as corrosion which can lower pH and negatively affect the performance.  By running some foam through the lines, this allows any contamination caused by the pipe to be cleared out and for a clean, representative sample of the foam to be collected. 

Sediment found in foam can also affect foam equipment as well as the foam performance.  For this reason, some specifications do require that a foam contain less than a defined percent of sediment.  Failing to clean the line before collecting can result in an unrepresentative sample and lead to some costly false conclusions about the integrity of the foam.

There are some important differences between firefighting foams that are alcohol resistant and foams that are not. Alcohol resistant (AR) foams work on both polar (alcohol) and non-polar (hydrocarbon) solvents whereas non-AR foams, such as standard Aqueous Film Forming Foam (AFFF) or protein-based foam, only work on non-polar solvents.

Foam blankets are mostly water.  Water, which is polar, will mix with polar hazards, like alcohols, thus causing the foam blanket to collapse and be rendered useless. Therefore, a barrier is often needed to prevent the foam from collapsing.  Most AR foams currently contain a high molecular weight polymer ingredient which gives rise to the foam’s alcohol resistance. The polymer forms an insoluble membrane between the foam blanket and the flammable hazard, as in Figure 1.

Video - How Paint Affects Sprinkler Performance

The 2017 Edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems requires an annual floor level inspection per 5.2.1 and any sprinkler that shows signs of paint, other than that applied by the sprinkler manufacturer, must be replaced.  The reasoning behind this is that any paint applied after the sprinkler has left the manufacturing process could impact the performance in both the coverage pattern and thermal sensitivity.  Dried paint in the deflector could prevent water from reaching the desired areas during a fire and dried paint on the release mechanism or water seal could insulate or prevent release, respectively.

To illustrate the thermal sensitivity performance issues caused by aftermarket painting, sprinklers with and without paint were tested at Dyne Fire Protection Labs in the Plunge Test Oven to determine response time.  Three different types of sprinklers were chosen to illustrate that paint can affect different thermal response elements.  Figure 1 shows the sprinklers chosen for this study.

When sending in foam concentrate samples to a laboratory to determine its continued performance for inspection, testing and maintenance purposes, it is important that the sample is representative of the tank to ensure safety, receive quick and accurate results, and to limit future retesting expenses. It is also important to realize that a foam concentrate tank is not always uniform throughout so it can be beneficial to take a sample from two different areas of the tank, specifically the top and bottom of the tank.

By Jennie Novak

Our goal at Dyne Fire Protection Labs is to make testing Quick, Easy, and Accurate. With just a few clicks or a phone call, we put a foam sampling kit right in your hands. Our firefighting foam/antifreeze kits include plastic bottles and caps, a pen for filling out the form, an etching marker to write on the sample bottles, a return shipping label, and paperwork to submit with the sample(s). We also have a fillable PDF of this same form, which allows you to save the logistics, therefore saving time.

What can you do when the kits arrive to make the process quick once we get them back for testing? Filling out the form completely and accurately helps ensure that the samples are entered for testing correctly, the report lists the information you will need to resample next year, and the reports get to the right people.

We realize that often times the person completing the paperwork is not always the same person that collected the samples. This article will help everyone from the technician to the administrative staff understand what information is needed on the form.

By Grant Lobdell

The 2017 Edition of National Fire Protection Association (NFPA) 25 “The Standard for the Inspection, Testing, and Maintenance of Water Based Systems” states in section 5.3.1.2, “A representative sample of sprinklers for testing shall consist of a minimum of not less than four sprinklers or 1 percent of the number of sprinklers per individual sprinkler sample, whichever is greater.”  Furthermore, some suggested guidance on what defines a sprinkler sample is given in the explanatory section of the Annex of NFPA 25 where A.5.3.1.2 states, “Within an environment, similar sidewall, upright, and pendent sprinklers produced by the same manufacturer could be considered part of the same sample, but additional sprinklers would be included within the sample if produced by different manufacturers.”  

Dealing with foam system proportioning issues can be frustrating and time consuming.  This guide is designed to help explain what the requirements are and what you can do when your system isn’t proportioning correctly.

NFPA Requirements

The National Fire Protection Association (NFPA) requires the concentration be verified when the system is installed as part of the acceptance tests.  NFPA 11 “Standard for Low-, Medium- and High-Expansion Foam” requires a foam system to proportion at no less than the rated concentration and no more than 30 percent or plus 1 percentage point (whichever is less) above the rated concentration.  Note, the same criteria are also a requirement of NFPA 16 “Installation of Foam-Water Sprinkler and Foam-Water Spray Systems.” Table 1 provides a list of acceptable solution concentration ranges for typical foam concentrates meeting the NFPA recommendations.

What companies can test for the presence of PFOS/PFOA in my firefighting foam?

Dyne currently does not offer any fluorosurfactant identification services. There are a variety of other companies, however, that can test for the presence of fluorosurfactants in firefighting foam.

There are labs accredited by the United States Department of Defense (DoD) to test for PFAS by LCMS/MS according to QSM 5.1 Table B-15.  The list of these labs can be found through their online portal https://www.denix.osd.mil/edqw/accreditation/accreditedlabs/.

Dyne Fire Protection Labs is proud of our talented and integral staff. The June 2017 newsletter article Meet the Dyne Team - The Faces Behind the Reports is a look at some the faces behind the reports and a little bit about each of us. 

In October 2007, the International Maritime Organization (IMO) Sub-Committee on Fire Protection released a formal proposal to amend MSC/Circ. 799 due to concern regarding the ability of alcohol-resistant (AR) protein-based foam to perform effectively on alcohols or other polar solvents. These proposed amendments, among many others, were approved and released by the IMO Maritime Safety Committee in June 2009 in the “Revised Guidelines for the Performance and Testing Criteria, and Surveys of Foam Concentrates for Fixed Fire-Extinguishing Systems,” which can be found in the annex of MSC.1/Circ.1312. These revisions require alcohol-resistant and protein-based (including AR fluoroprotein-based) concentrates to be annually subjected to a small-scale fire test as well as a stability test with acetone.

*UPDATE: As of April 2017, Dyne Fire Sprinkler Test Report’s now reflect when a sprinkler passes or fails a requirement.”, see the Sprinkler Sample Report for an example. 

*UPDATE: As of March 2017, Dyne will no longer be checking sprinklers for recalls, see the Blog article for more details.

It is important to send in a sample of sprinklers to be tested by a recognized testing laboratory such as Dyne Fire Protection Labs to ensure that a sprinkler system will work properly in the event of a fire.  Dyne completes an appearance inspection as well as a test of the response time of the sprinklers received in our laboratory.  In addition, Dyne will check the sprinkler to ensure it is not part of a sprinkler recall.*  Any test that does not meet the National Fire Protection Agency (NFPA) 25 requirement will show up as “Out of Specification” on the test report.

Dyne Technologies, LLC is pleased to announce that dry sprinkler testing is now available, in addition to the sprinkler testing service that we introduced on December 1, 2016. As with its existing services, Dyne will offer guaranteed turnaround time, online reports, accurate and reliable results and unparalleled customer service.

Along with testing, we are also introducing a test kit for dry sprinklers which will be available in two adjustable sizes. Each kit will be able to hold one dry sprinkler—the smaller size adjusting to fit a sprinkler up to 20”, and the large fitting a sprinkler from 21” to 42”. Dyne will pay the shipping for the kits to you, however because of the variability in the size and weight of dry sprinklers, customers will be responsible for shipping costs back to Dyne Technologies. There is a cost associated with these kits: $10 each for the smaller size, $12 each for the larger; the pricing for testing will remain the same as with our standard sprinkler head testing.

*UPDATE: As of April 2017, Dyne Fire Sprinkler Test Report’s now reflect when a sprinkler passes or fails a requirement, see the Sprinkler Sample Report for an example. 

*UPDATE: As of March 2017, Dyne will no longer be checking sprinklers for recalls, see the Dyne Blog for more details.

Dyne Technologies, LLC is pleased to announce its new testing service – sprinkler testing. The NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems requires that field sprinklers be either tested or replaced at periodical time frames. Dyne is adding this testing service to its well-established offerings of firefighting foam and antifreeze testing. As with its existing services, Dyne will offer guaranteed turnaround time, free test kits and shipping (within the continental United States), on-line reports, accurate and reliable results and unparalleled customer service.

All film forming foams are required to demonstrate their film forming ability during the periodical testing. Film forming foams include aqueous film forming foams (AFFF), alcohol resistant AFFF (AR-AFFF), film forming fluoroproteins (FFFP), and alcohol resistant FFFP (AR-FFFP). The film described by their names is an aqueous film that forms on the surface of the flammable liquid. This is possible because these foam concentrates contain surfactants. Surfactants are chemicals that alter the surface properties of water, which can, depending on the surfactant(s) used, allow for the thin layer of film to be formed over the fuel. This film isolates the fuel from the oxygen and ignition source even when the foam blanket is removed. Foams such as regular proteins or high expansion foams are not designed to have this film feature and rely solely on their foam blanket.

The pH is tested on every fire-fighting foam concentrate sample sent to Dyne Technologies.  The pH can help indicate the condition of the foam concentrate.  For samples tested to NFPA 11, pH is not a measurement of performance and will not cause a sample to fail.  However, a concentrate being tested to International Maritime Organization (IMO) Specification MSC 1312 and NFPA 18 Standard on Wetting Agents requires foam concentrate to have a pH within a set range to be acceptable.

The viscosity of firefighting foams are measured if they are thick in nature – typically alcohol resistant (AR) foams. This physical property can be critical to ensuring the foam has maintained its alcohol resistance properties. It can also offer insight into potential problems, such as dilution or polymer separation.

What is Viscosity?

Viscosity is the measure of internal friction. Simply put, it measures how much resistance an object would have when traveling through a sample. The more viscous a sample, the more resistance there is to an object traveling through it. This friction applies to how the foam will move through your proportioning equipment. The more viscous the sample is, the slower it will move through the system. This gives rise to the need for listed equipment and flow rates for each firefighting foam.

The density is determined on all firefighting foam samples that are tested at Dyne. The density on a Dyne report is the amount of mass per given volume (g/mL). It is an important physical property that can quickly help identify any potential problems that might be occurring with the foam.

What is Density?
Density is defined as a quantity per given space, in other words, how much material is in a defined spaced. Most commonly, the density is reported as a mass per given volume as the quantity and space, respectively. To determine this density, you can measure the mass of a specific volume or vice versa (measure the volume of a specific mass). The calculated density would simply be the mass divided by the volume. At Dyne, we report the density with the units of g/mL which comes from this division – the amount of mass (g) per volume (mL). For example, the density of water at room temperature is about 0.998 g/mL. That means that if we poured out 1 mL of water, the mass of that water would be 0.998 g.

Dyne Technologies is now offering two new types of rental kits for in-field use.  First, a conductivity rental kit with everything that is needed to estimate the percent concentration of foam in premix solution in the field. Because of the quick results, adjustments are easily completed in the field. See the kit description below.

Refractive index is an effective and important physical property that can give insight into the quality of a firefighting foam, premixed solution, or bladder water sample. The refractive index is a measurement of the angle in which light bends as it passes through a substance and is proportional to the amount of solvent present in a sample.

Dyne Technologies performs various physical property tests in order to better understand a firefighting foam sample. An important physical property that can tell us a lot about a sample is the appearance, which is the description of the color, consistency and the visible presence of sediment and particles.

Maintaining proper storage conditions is vital to ensuring the lifespan of firefighting foam. Each foam manufacturer has recommendations in their product’s technical datasheet that typically discuss storage material, storage temperature, and any other special considerations for storing the foam. Understanding how each of these items impacts the foam can help identify potential problems before they happen.

At Dyne Technologies, we take the quality of our service very seriously.  Using our vigorous testing and approval processes, we monitor all results to confirm that the results are precise and accurate.  We are an ISO 9001:2008 certified laboratory.

It is imperative that your fire-fighting foam is matched to your hazard. Only certain types of foam, proportioned at a specified concentration, will extinguish water soluble flammable liquids.  Click on the PDF link below to take a look at a list of common flammable liquids and the type of foam that is required to protect them. 

As of September 7th, 2015, the 2016 edition of NFPA 11: Standard for Low-, Medium-, and High-Expansion Foam was approved as an American National Standard. This new edition, which replaces the 2010 Edition of NFPA 11, has several changes that addressed areas of concern that arose since that last addition. The committee stressed that some piping requirements have been addressed, more environmentally friendly on site proportioning testing has been recognized, and acceptance criteria for the annual testing of foam concentrates has been clarified. Dyne Technologies would like to highlight some of the changes that affect the annual inspection and testing of your foam systems.

You may notice on Dyne test reports that the test categories are grouped into physical properties and performance properties. Physical properties tested on all foam and premix solution samples include Appearance, Refractive Index (if applicable), pH, Density, and Viscosity (if applicable). The physical properties are not a measurement of performance and will not typically cause a sample to fail, with the exception of extremely low viscosities on AR-AFFF samples and out of spec pH results for foam tested to the International Maritime Organization (IMO) specification. The data provided by the physical properties is very valuable, as it gives information about the quality of the foam and how the foam has changed since first manufactured.

Water-based fire protection systems that use antifreeze solution need to be inspected, tested and maintained regularly in order to ensure performance. NFPA 25: Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, 2014 Edition requires any water-based piping exposed to temperatures below 40 degrees Fahrenheit to use antifreeze solution and recommends the following.

All firefighting foams work to suppress fires using the same concept, however, different types of foams have different properties that are designed for different applications in the field.  Dyne technologies is able to test these different types of firefighting foam, including high expansion foam.

The United States Environmental Protection Agency (US EPA) is encouraging manufacturers to phase out of manufacturing the larger chain synthetic fluorinated chemicals in favor of fluorochemicals with six or less carbons-the smaller chain fluorochemicals are considered to be more environmentally friendly.  Understanding what this change means, the history behind it, and how it affects the firefighting foam industry will make this transition a lot easier.

Filling out the paperwork for a sample of firefighting foam to send into Dyne for testing can be confusing if you are unfamiliar with some of the language or testing methods used in the firefighting foam business. One choice that must be made is if the sample must be tested to International Maritime Organization (IMO) or National Fire Protection Association (NFPA) specifications. IMO and NFPA have similar standards for firefighting foam testing except IMO stipulates a slightly more rigorous analysis.

The National Fire Protection Association (NFPA) “Standard 11 Low- Medium- and High-Expansion Foam” recommends a foam system proportion at no less than the rated concentration and no more than 30 percent above the rated concentration. Note, this same criteria is also a requirement of Underwriters Laboratory (UL) specification 162 “Foam Equipment and Liquid Concentrates”. Table 1 provides a list of acceptable concentration ranges for typical foam concentrates meeting the NFPA and UL recommendations.

Knowing what foam you have is vital to the safety of the lives and property you are protecting. The type of foam used must be able to protect against the hazard present. When submitting a sample to Dyne, mislabeling the type of foam can lead to false results. To help better assist you in knowing your foam and getting it tested appropriately, below is a summary of the common foam types which are tested at Dyne.

Verifying that a firefighting foam system accurately proportions foam and water is critical to the system’s effectiveness in the event of a fire. If the premix solution is mixed too lean—not enough foam concentrate and too much water—it may not be able to extinguish the fire. If the premix solution is mixed too rich—too much foam concentrate and not enough water— there is a risk running out of foam before the fire is fully extinguished.

Bladder tanks are commonly used to store and proportion foam concentrate in foam systems. A bladder tank consists of a carbon steel tank with an inner elastomeric bladder. Foam is stored inside this bladder while water is directed through piping to the area between the steel tank and the bladder. The resulting water pressure is used to force the foam out of the bladder and into a controller which then mixes the correct concentration of foam (which is typically 1 to 6 percent) into the water.

Mineral oil is sometimes added to the top of alcohol-resistant aqueous film forming foam (AR-AFFF) by the manufacturer to prevent evaporation of the solvent in the foam concentrate. Most often, mineral oil sits on the top of the container that foam concentrate is housed in. If a sample of the foam concentrate is taken from the top of the container, but care is not given to take the sample under the mineral oil layer, annual testing can result in failing results.

Colder temperatures are on their way throughout much of the United States and with colder temperatures comes new challenges to maintaining and protecting your water based fire protection systems. These systems must be in compliance with NFPA® 25 – Standard for the Inspection, Testing and Maintenance of Water-Based Fire Protection Systems - and Dyne Technologies is here to help with your testing needs.

Physical Properties

The physical properties described below are tested on antifreeze solutions sent to Dyne Fire Protection Labs. The physical properties are not a measurement of performance and as such will not cause the sample to FAIL. If the value is outside of the specification, it is simply noted as OUT OF SPEC.

Changes to Foam Testing Specifications

The National Fire Protection Association Standard 11 entitled Standard for Low-, Medium-, and High-Expansion Foam is in the 2014 fall revision cycle at NFPA. As such, several key process steps have been completed to move this standard from the 2010 version to the new 2014 version. The new revision should be issued this fall. The first draft of the new version was issued in September of 2013; and the posting of the second draft and the technical committee ballot is scheduled for June 13, 2014.

The National Fire Protection Association (NFPA®) has released the 2014 edition of NFPA® 25 – Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems. The 2014 edition of NFPA® 25 has many changes since the last edition. Dyne Fire Protection Labs is highlighting the changes that are in relation to foam and antifreeze solutions to ensure our customers are aware of the new standard, and help them understand the impact of these changes. Please note, this article does not identify all the changes to NFPA® 25. If you have any questions regarding this standard, view the standard at www.NFPA.org.

In an emergency flammable liquid fire situation, reliance on safety personnel, local police and fire departments, and foam performance are required for a successful fire knockdown. Training is commonplace for safety officials but foam testing is overlooked in many fire departments across the country. As specified by NFPA 11: Standard for Low-, Medium-, and High Expansion Foam, fire-fighting foam should be tested at least annually by the foam manufacturer or an independent laboratory. Poor performance of fire-fighting foam may be caused by water dilution, tank corrosion or failure to follow the manufacturer’s tank and sample requirements. For these reasons, it is recommended that safety personnel fully understand the basics of fire-fighting foam and that foam testing should be conducted at least annually, to ensure the best performance when it is needed most.