Frequently Asked Sprinkler Questions - September 2019
By John Langteau
At Dyne Fire Protection Labs, we get many questions from customers who are sending in sprinklers for testing about what’s allowable/acceptable with sprinklers. This article looks to answer the more common questions, using NFPA standards and our own experiences.
Can a loaded sprinkler be cleaned?
According to the current, 2017 edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, sprinklers that have a light coating of dust or debris may be cleaned using compressed air and or a vacuum. A blast of compressed air or vacuum may be used to remove the dust or debris while the sprinkler remains in place. While the cleaning is taking place it is important to not touch or damage the release mechanism of the sprinkler, whether it is a glass bulb or a fusible link. At no time should any chemical cleaning product be used on the sprinkler either liquid or aerosol. It is recommended that any sprinkler that cannot be cleared of detrimental dust or debris shall be replaced (Figure 1).
Listed or Approved - How to Find and Interpret Foam Concentrate UL Listings - August 2019
According to Chapter 4 of the 2016 edition of NFPA 11 Standard for Low-, Medium-, and High-Expansion Foam, the components of a foam system, including the foam concentrate itself, shall be listed. Where listings for a component do not exist, the components shall be approved.
What does NFPA mean when it states a component needs to be listed or approved?
NFPA defines the term listed as follows:
Equipment, materials or services included in a list published by an organization that is acceptable to the authority having jurisdiction and concerned with evaluation of products or services, that maintains periodic inspection of production of listed equipment or materials or periodic evaluation of services, and whose listing states that either the equipment, materials or service meets appropriate designated standards or has been tested and found suitable for a specified purpose.
Simply put, a listed product or service is one that has been evaluated by a third party to do what it claims. Furthermore, this third party is also tasked with periodically ensuring continued compliance to ensure no shortcuts in production or service are taken after achieving the listing.
Is Your Foam-Water Proportioner Working Properly - July 2019
An in-depth look at NFPA 11 and 25 percent concentration testing and what you can do about it in the field
by Grant Lobdell
Authority Having Jurisdiction (AHJ) - June 2019
by Grant Lobdell
All National Fire Protection Association (NFPA) documents reference an authority having jurisdiction (AHJ) at some point or another. For example, per 22.214.171.124 in the current, 2017 edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, “sample sprinklers shall be submitted to a recognized testing laboratory acceptable to the authority having jurisdiction for field service testing.” To fulfill requirements such as these, a person needs to know what and who their AHJ is.
The Shelf Life of Firefighting Foam - May 2019
by Joan Leedy
At Dyne, we are often asked “What is the shelf life of my firefighting foam concentrate?” And the answer is – that depends. There are many factors that can affect shelf life. I will discuss the major ones here.
The Brand and Model of Foam – Though there are some similarities among the foams produced today, none are identical and some formulations will have longer shelf lives than others. Check with the manufacturer of your foam to obtain a shelf life estimate. Manufacturers typically run accelerated aging studies to predict the shelf life of a formulation.
Materials of Construction – The foam manufacturer should be able to provide acceptable materials of construction for storing their respective foam concentrate in order to maximize shelf life. This will include the tank, piping materials, valves, pumps and other surfaces that come in contact with the foam concentrate.
The 2016 edition of the National Fire Protection Association Standard 11 - High, Medium and Low, Expansion Foam also provides recommendations on the materials of construction in contact with firefighting foam concentrate. NFPA 11 recommends that foam concentrate piping and fittings be constructed of brass (red or naval), bronze, stainless steel (304 or 316) or “other material, in accordance with the foam concentrate manufacturer’s certification of compatibility with the foam concentrate and as approved by the AHJ”. Carbon steel piping or fittings is not recommended for use with foam concentrate. See NFPA 11 Section 4.7.
An additional concern with materials of construction can be galvanic corrosion when using dissimilar metals. Dielectric components are recommended to insulate dissimilar metals – see NFPA 11 section 126.96.36.199.
Sprinkler Sensitivity Requirements - April 2019
by Grant Lobdell
According to the current, 2017 edition of NFPA 25 Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems, sprinklers are to be sent in for field service testing on a periodical basis according to 5.3.1. This field service testing is further defined in the annex of the standard under section A.188.8.131.52 stating that sprinklers should be laboratory tested for sensitivity and functionality, specifically. While the 2017 edition of NFPA 25 does discuss sensitivity and functionality requirements to some degree, the upcoming 2020 edition of NFPA 25 will have much more defined requirements.* Note that these requirement changes have already been implemented at Dyne and other sprinkler labs across the country. For periodical testing purposes, a sprinkler is functional if the waterway clears at 7 PSI. The periodical sensitivity requirements for a sprinkler will be defined as shown in Table 1.