Articles

Sprinklers shall be inspected from the floor level annually for these signs

By Grant Lobdell, General Manager and as seen in the November 2021 edition of - FPC - Fire Protection Contractor Magazine

According to the current, 2020 edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, “sprinklers shall be inspected from the floor level annually.” (5.2.1.1) Any sprinkler that shows signs of any of the following shall be replaced according to 5.2.1.1.1:

• Leakage
• Corrosion detrimental to sprinkler performance
• Physical damage
• Loss of fluid in the glass bulb heat-responsive element
• Loading detrimental to sprinkler performance
• Paint other than that applied by the sprinkler manufacturer

By Grant Lobdell, General Manager

The current, 2021 edition of NFPA 11 Standard for Low-, Medium-, and High-Expansion Foam defines a synthetic fluorine-free foam (SFFF) as a “foam concentrate based on a mixture of hydrocarbon surface active agents that is not formulated to contain per- or polyfluoroalkyl substances (PFAS).”  Preferring something more analytical, several organizations have taken it upon themselves to define or are currently considering defining the amount of PFAS more quantitatively.  For example, Clean Production Action’s GreenScreen Certified^TM Standard, which is advertised as “the world’s first ecolabel to confirm fluorine-free firefighting foam products”, defines the term fluorine-free as “zero intentionally added PFAS to the product and PFAS contamination in the product must be less than 0.0001 percent by weight of the product (1 part per million) total organic fluorine as measured by combustion ion chromatography.” The standard technical panel for UL 162 Standard for Foam Equipment and Liquid Concentrates is also currently considering a similar, quantitative limit for an upcoming revision which is to include several additions and changes concerning SFFF specifically. 

Current NFPA 25 Requirements and Explanatory Material

By Grant Lobdell, General Manager

This article was featured in the September 2021 edition of FPC/Fire Protection Contractor magazine. 

By Joan Leedy, Technical Director

Maintaining fire protection systems onboard ships is critical to the safety of the crew as well as the cargo, ship and the environment. Maintaining a fixed dry chemical powder system is no exception. SOLAS describes testing and maintenance requirements for this type of system which includes the requirement to sample and test the dry chemical for moisture content, at a minimum of every two years.

By Grant Lobdell

Regulations concerning per- and polyfluoroalkyl substances (PFAS), a group of thousands of manmade and persistent molecules, continue to grow. Where previous regulations on firefighting foam referenced limits on just two specific molecules within this group, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), some regulations are now calling for a limit on all PFAS.

PFOA and PFOS Analysis

PFOA and PFOS, which I will refer to as PFAS species, are generally isolated using liquid chromatography (LC). Chromatography is a laboratory technique that involves the separation of molecules based on their attraction to the material of a tube they are passed through. This tube is typically referred to as a column. The more attracted the molecules are to the material of the column, the slower they travel through it. Given enough column length, even very small differences in this attraction can add up to a significant change in how long it takes the molecule to pass through the column, which is commonly referred to as retention time. A laboratory can use this to their advantage. Knowing how long it takes each molecule in a solution to pass through a column, the laboratory can put a sample containing multiple molecules into the column and get out a sample each specific molecule at a specific time.

To determine total PFAS content in this way, though, the laboratory would have to isolate and quantify each one of the thousands of PFAS species. The sum of all the PFAS species present in a sample would equal the amount of total PFAS. Unfortunately, there is not a column available which can separate all these species by itself. Many columns would be needed. Furthermore, to determine the retention time of each PFAS species on a column, one would need a pure example of each molecule, some of which are certainly not readily available. Therefore, this speciated approach would not be very economical even if it were possible for total PFAS analysis. If a laboratory is using this approach and reporting total PFAS content, they would simply be looking at just a handful of PFAS species and assuming all others are negligible. Therefore, they could be under reporting total PFAS content.

Total Organic Fluorine

All PFAS, by definition, are organic molecules that contain fluorine chemically bonded to carbon. It is important to note before moving on that organic as it is used here does not refer to whether it is manmade or found in nature. The label organic in chemistry refers to the carbon-based structure of the molecule.

The fluorine found bonded to carbon in PFAS, which is referred to as organic fluorine, is a unique feature shared by all PFAS species. Therefore, it makes for a great indicator when looking at PFAS as a whole. Instead of looking for the thousands of individual PFAS species, a laboratory can look for just organic fluorine, which is much more feasible.

To quantify the amount of fluorine in a sample, a laboratory would use combustion ion chromatography (CIC). In this process, the sample is first combusted to break any carbon-fluorine bonds found in the sample. Given the carbon-fluorine bond is one of the strongest chemical bonds, the sample needs to be heated to beyond 1000°C for it to be broken. Once the sample is combusted and the fluorine is no longer attached to carbon, it can then be quantified by ion chromatography (IC). Ion chromatography is very similar to the liquid chromatography process except that it is looking for just parts of a molecule, not the whole molecule itself. These parts of the molecule in this case are referred to as ions. The fluoride ion is separated from all other ions in solutions in a column. Once isolated, it can then easily be quantified.

The amount of fluoride determined by combustion ion chromatography would be the amount of total fluoride (TF) in the sample. Unfortunately, this value by itself may not accurately reflect total PFAS. Fluoride, after all, can come from more than PFAS. It can be found as a salt or mineral, which are referred to as inorganic molecules given they lack that carbon structure defining organic molecules. People come into contact with these inorganic molecules every day. Toothpaste and municipal water generally contain inorganic fluoride given its ability to help prevent tooth decay. This inorganic fluoride can also be referred to as free fluoride where the free label comes from the fact it is not bonded to carbon.

To get a sense of total PFAS, what is actually needed is total organic fluorine (TOF) not total fluorine (TF). Luckily, it is relatively straight forward to determine total organic fluorine from the total fluorine result. The amount of free fluoride in the sample to begin with just needs to be quantified and subtracted out. There are a variety of ways to determine free fluoride. An ion selective electrode (ISE) could simply be used for this. The sample could also be run through the ion chromatography column again but this time without the combustion step so that the organic fluorine remains attached to carbon and therefore is undetectable by ion chromatography. Regardless of how free fluoride is determined, if it is accounted for and subtracted from the total fluorine result, we are left with the amount of total organic fluorine which is a direct reflection of total PFAS content.

Meet the Dyne Team - The Faces Behind the Reports

by Joan Leedy, Technical Director

NFPA 11 The Standard for Low-, Medium- and High-Expansion Foam recommends that foam proportioning systems be tested when installed and yearly thereafter.

NFPA 11 Section 12.6.5 states “The foam concentrate induction rate of a proportioner, expressed as a percentage of the foam solution flow (water plus foam concentrate), shall be within minus 0 percent to plus 30 percent of the manufacturer’s listed concentrations, or plus 1 percentage point, whichever is less.”

by Grant Lobdell, General Manager

Whether it be due to corrosion or loading, sprinkler performance often degrades over time.  For this reason, the current 2020 edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems states that sprinklers shall be initially tested or replaced after 50 years in service.  However, a few notable exceptions exist in the standard.  Dry sprinklers, which have had a high failure rate for many years due to the prevalence of the O-ring design, and fast response sprinklers, which are a newer technology compared to standard response sprinklers, shall be initially tested or replaced just 15 years (previously 10 years in prior editions of NFPA 25) or 20 years after install, respectively.  Furthermore, any sprinklers exposed to a harsh environment require testing or replacement every 5 years unless it is specifically listed as corrosion resistant in which case the testing or replacement frequency is decreased to every 10 years.