Tepid water solutions
Responding is Michael Bolden, director of marketing and sales, Encon Safety Products Inc., Houston.
In 2009, the International Safety Equipment Association published the revised ANSI standard (Z358.1-2009) for emergency eyewash and shower equipment to incorporate a delivery of tepid potable water at a temperature range of between 60° F and 100° F. Although tepid water has been discussed for years, this was the first time it was placed in the ANSI standard. However, the wide range in temperature should be closely scrutinized by each employer. I doubt anyone would last 15 minutes in a shower that is running at 60° F. Even the upper range might be too uncomfortable depending on the type of exposure or injury. Narrowing the range down to between 80° F and 90° F might be more practical when determining the precise temperature range to consider.
After determining the proper range, a close inspection by a qualified emergency shower and eyewash manufacturing engineer or specialist should be completed to assess the proper type of tepid water solution your facility might need.
Several types of solutions are available; however, it is essential that the proper solution performs as you would expect and meets the ANSI standard. The most prevalent solutions offered today are air driven, steam driven and electrical tempered water systems. All take heated potable water and a cold potable water supply and blend them to the desired tepid temperature. It is highly preferred for the blending system to have a fail-safe mechanism to avoid scalding temperatures in the event of a blending valve failure. Scalding water can exacerbate the injured skin tissue and prevent the user from being able to remain under the irrigation system for the full 15 minutes needed.
An additional form of water tempering for shower and eyewash stations is instantaneous water heating. This typically is done with an electrical instantaneous water heater. However, other methods are available. The cost to operate these units is substantial from a resource standpoint, so the initial savings might be outweighed by the length of service you get out of this type of unit and the cost to actually operate it.
Tepid or tempered water solutions also can provide multiple showers and eyewashes with simultaneous irrigation, when sized properly. However, the most critical issue is to ensure your expectations are met. How many units do you logically need to be activated at once? The ANSI Z358 standard requires each unit to have a minimum flow of 20 gallons per minute for showers and 0.4 gpm for eyewash units. This has to be achieved simultaneously, whether with one unit or several.
So what kind of tepid water system do you need? As mentioned previously, your emergency shower and eyewash professional can survey your simultaneous needs with a walk-through survey of your facility. Most of this can be done with little to no initial cost. Making sure the right solution is chosen can take some research. By consulting professionals, you can meet your expectations and protect valuable lives when an emergency arises.
Editor's note: This article represents the independent views of the author and should not be construed as a National Safety Council endorsement.