Engineered Solutions: A Win/Win Situation!
Do the showers, eyewashes, or combination units in your system compensate for pressure changes and still attain the minimum operating flow heights and patterns?
- By Casey Hayes
- Sep 01, 2004
WE see it in all areas of our lives: The more complex something becomes, the more likely we are to need someone who specializes in it. So it is with emergency equipment design, specification, installation, and maintenance.
Urban legend has it that the first emergency eyewash was designed by a concerned plant supervisor who fashioned an eyewash out of spare drinking fountain bubblers. In my mind, that's closely akin to trying to halt a four-alarm blaze with a garden hose. But, I suppose everything has to start somewhere!
Starting from those rather modest beginnings, the combination of heightened concerns about worker safety, much higher risks associated with technical and manufacturing advancements, and an increase in governmental safety regulations have significantly and justifiably complicated matters. Today, between ANSI and OSHA we have a fundamental safety net that requires compliance to very specific standards of safe operations, preparations in the event of an accident, and appropriate response mechanisms.
Traditionally, we have had a logical plant safety progression of:
- Identification of a threat, via OSHA standards and other health and safety guidelines, as well as through internal audits and review procedures
- Definition of appropriate precautions, in terms of operational parameters and Personal Protective Equipment (PPE)
- Preparation for accident response, through the application of safety equipment installed in accordance with the appropriate standards.
This reasonably straightforward approach still works well, although the scope of each of the three areas continues to broaden dramatically. For instance, a single industrial spill/splash threat from a caustic agent used in manufacturing still carries appropriate precautions and responses if an accident occurs. However, today the threat might be broadened due to the potential for intentional spills/splashes (terror, worker violence, etc.) and through a deeper understanding that the traditional responses to an accident may carry their own negative consequences. For example, a caustic splash victim might encounter evaporative cooling during a fifteen-minute drench shower cycle, possibly leading to hypothermia. So, while our logical progression still applies, each step in the progression is much more complicated and requires much more thought and planning.
This situation continues to complicate the specification of emergency response systems. What used to be a relatively simple task of defining one's risks, applying the needed precautions, and preparing for accidents by linking together "appropriate" emergency equipment components has become a science unto itself. The selection and matching of complimentary components that work together within the limitations of space, water pressures, and potential simultaneous use of multiple showers, with appropriate redundancies and integrated safeguards, is certainly more than can be ascertained by looking through catalogs. If there ever was an example of complexity leading to specialization, this is it!
Turnkey safety entails custom engineered installations that specifically identify the entire need and custom match emergency equipment componentry into an Engineered SolutionTM that cost-effectively addresses that need.
The driving force behind the acceleration into turnkey safety thinking has primarily been the need for tempered water. That, along with the necessity to adhere to ever-tougher ANSI Standards, has forced specifiers into treating their complete installation as a "system." While you might think this is a subtlety, I assure you it is not. If you're considering an emergency shower apparatus as an individual component, that's one thing. But think about that same shower as part of a plant-wide fully engineered system that has to deliver tempered water at a specific pressure, for a specific use cycle -- with the possibility that multiple showers may be in use simultaneously. You start to get the idea!
First, a tempered water blending system valve, at the heart of today's state-of-the-art engineered emergency system, must have the capability of not only compensating for input water temperature changes, but also providing for cold water by-pass in the event of hot water failure -- an engineering feat in itself. Next, consider the maximum load requirements of simultaneous use on both the total water supply and the tempering system, also taking into account the geography covered by the linked system. Do you have sufficient water -- both volume and pressure -- for maximum load use? Do you need a booster pump? Is the volume and recovery time of your tempering system sufficient to maintain "tepid" conditions with maximum load use? Finally, consider the showers, eyewashes, or combination units in your system. Do they individually have the capability to compensate for pressure changes, due to line pressure fluctuations and/or simultaneous use situations, and still attain the minimum operating flow heights and patterns?
And all of that hasn't begun to consider things like the cost penalties of over-specing a single piece of the total system versus the other components, the impact of remote operations where water and/or power may be issues, or the need for reverse tempering. Reverse tempering is appropriate in areas where the ambient temperatures heat the water in emergency equipment piping to a point where it is too hot to be used without cooling. This can happen due to either operation in a warm climate or proximity to hot manufacturing and/or processing operations.
Turnkey safety can be as simple as specifying an engineered valve system to control your tempering operation or matching a single combination shower/eyewash to assure that using both the shower and eyewash simultaneously won't diminish the flow of either to below prescribed levels. Piecing a tempering valve system together is a great way to forget even one variable and create a possibly worse situation than you're trying to address. And, you'd be surprised at the combination shower/eyewash products on the market that don't offer flow controls in them.
Beyond the obvious, single product "systems," the next consideration might be a skid-mounted system that provides matched components for tempered water heating, blending, and circulation. That basic platform can be built to feed a single shower or multiple units over a prescribed plant geography -- once again, no small feat. It can also be built to incorporate a shower or combination unit right into the skid, with or without the ability to tap into the tempering system for other nearby showers.
Finally, that same basic platform, with or without additional componentry, can be encased in a booth, making it a fully self-contained turnkey system. When these booths are configured with showers, we refer to them as Enclosed Emergency Environments (E3). They are custom-engineered, matched, and balanced turnkey systems that are highly visible, private safe-havens for the injured.
Engineered SolutionsTM are the future, because they provide the ability to have a matched and balanced system designed for your particular needs by specialists who deal with the wide variety of available options and approaches every day. It's definitely a win/win situation -- actually it would be more appropriate to call it a win/win/win! The specifier wins in that you know your needs will be appropriately addressed. The manufacturer wins in that we know precisely what you need and are better able to assist you. And employees win in that they have the best emergency treatment available for their specific needs.
For more information on Turnkey Safety and Enclosed Emergency Environments, please visit www.hawsco.com/jg.
This article originally appeared in the September 2004 issue of Occupational Health & Safety.