Privately-owned water tanks supplying fire protection systems have a long history. The NFPA published the Standard on Gravity Tanks in 1909. It is one of the oldest NFPA codes, predating even the Life Safety Code’s precursor, the Building Exits Code, first published in 1927. The Standard on Gravity Tanks evolved over the years to become NFPA 22, Standard for Water Tanks for Private Fire Protection. The inspection, testing, and maintenance requirements for all types of private fire water storage tanks are laid out in NFPA 25, Chapter 9 – Water Storage Tanks. While there are about eight different types of fire water tanks, I’d assert that the most common type today is the steel suction tank. Read More
Fire protection water supplies can be made up of one or more common elements, including tanks, pumps, water sources and water systems. Sometimes elements are used together to develop an adequate supply for fire protection.
An adequate water supply for a fire protection system will meet the needs of the fire protection system (plus safety factor) in three terms: Read More
In my last blog, we discussed the small PRVs that go on wet sprinkler systems to limit their pressure below 175 psi. That brought to mind a small PRV in another application that is used to keep something different cool: an electric motor-driven centrifugal fire pump. I can’t talk about electric fire pumps without also talking about diesel fire pumps, so let’s dive in and take a look at both! Read More
Ah, summertime. Summer’s heat brings some good things: opportunities for outdoor swimming and seasonal produce: blueberries, and peaches, and watermelon…
Summer’s heat doesn’t bring all good things. It can even trigger issues with fire sprinkler systems. Let’s zoom in on a small component on a wet fire sprinkler system that’s there in part because of summer heating: a pressure relief valve.
A pressure relief valve (or an auxiliary air reservoir) is required on wet sprinkler systems; one reason is to Read More
In Part 1, we looked at the basic parts of a fire sprinkler and took a closer look at other parts including heat responsive elements, wrench bosses, and kick springs. In this part, we’ll look at k-factors and deflectors.
K-Factor and Orifice Size
K-factor is a characteristic that relates water pressure to flow rate from the sprinkler, represented as k in the equation Q = k√P, where Q is flow (gpm) and P is pressure (psi).
If we supply water at 50 psi to a k-factor 5.6 sprinkler, the flow rate is 40 gpm. If we supply 50 psi water to a K25 sprinkler, the flow rate is 177 gpm. There are now sprinklers as large as K33.6, which would flow 238 gpm given 50 psi – big difference from the K5.6!
The most common k-factors are 5.6, 8.0, 11.2, 14, 16.8, 22.4 and 25. There are smaller and larger k-factors than these. For reference, K5.6 and possibly K8.0 are most often found in Read More
In this blog we’ll take a look at the basic and some of the less-known parts of fire sprinklers, with more to come in a later post.
Here are the basic parts of the fire sprinkler, shown on a pendent glass bulb sprinkler and an upright solder element (“fusible link”) sprinkler:
Let’s take a closer look to learn about some of the less known parts, and also look at two types of sprinklers disassembled. Included in parentheses are some of the different names for some of these parts. Read More
Cooking equipment is the leading cause and is responsible for over half of fires in eating and drinking establishments (see Warren expert Chad Jones’ 2020 blog, Structure Fires in Eating and Drinking Establishments, for further reading on fire causes and NFPA 96 on duct inspection and cleaning). Fire extinguishing systems are also routinely provided over GREASE-producing cooking appliances. So why are some of these fires still so bad? GREASE is the word.Read More
In my two previous blogs, we first discussed wet sprinkler systems (Wet), the most basic and most common fire system type followed by dry sprinkler systems (Dry), which are a bit more complicated. Ratcheting up another level, in this last edition on sprinkler systems, let’s take a look together at preaction and deluge systems. These can be complex and variable, so we’ll operate at the 30,000 ft level. Read More
In my previous blog , I discussed the most basic and most common fire system type: wet sprinkler systems. The possible failure areas discussed with wet systems will also apply to dry sprinkler systems (control valves closed, obstructions, issues in the system, installation, or deficiencies with inspection, testing, and maintenance). Dry systems are even more prone to obstructions than wet systems, so close attention should be paid to that possibility. Read More
Please join us in welcoming Fire Protection Engineer Amy Anderson, P.E., to the WARREN family! Amy has over 20 years of property loss prevention engineering and experience, specializing in fire protection. Amy graduated from Clemson University with a degree in Chemical Engineering and is a licensed Professional Engineer in Fire Protection.