Better eyewash stations reduce injury
An eyewash station designed for treating chemical eye burns should be placed where a person in mid-emergency will find it easily and it must be operable without mistakes or confusion in a moment of crisis.
Chemical eye burns don’t stop burning. Unlike an impact or abrasion, where damage is done in an instant, chemical burns keep on doing harm until the hazardous substance is removed from the eye. Minimizing injury is a race against time. That’s why the standard for eyewash stations (ANSI Z358.1-2009 American National Standard for Emergency Eyewashes and Shower Equipment) dictates they must be accessible within 10 seconds of places where accidental exposure may be expected.
This means an eyewash station must be easy to get to at a time when the accident victim may be unable to see well and may be panicked. It must be easy to operate under those difficult conditions and it must work reliably.
One logical solution is to place the eyewash station at a sink, which is a place anyone familiar with the room will naturally turn in such an emergency. Several “faucet-mount” products that add eyewash heads onto existing faucets have been offered. However, they could present safety hazards involving delays in activation and the danger of scalding water being delivered to the eyes. Newer, specially designed combination products feature both eyewash and faucet functions that work independently. These integrated units are designed to solve the safety problems posed by faucet mounts.
Preventing injury and best practices
According to the U.S. Department of Labor Bureau of Labor Statistics, 27,450 workplace non-fatal eye injuries resulted in days out of work were reported in the U.S. in 2008. Of those, about 10 percent were from chemical burns. There were likely many more exposure injuries that did not result in days of lost work because they were treated quickly in eyewash stations.
Chemical burns get worse the longer they go untreated. Acid burns typically only damage the surface of the eye, but serious damage to the cornea can cause blindness. Alkali burns are often more damaging because they can penetrate and harm internal eye structures as well. As long as the harmful substance is in contact with the eye, the chemical reaction can continue. Worse, the damage may be increased by the natural, instinctive response of closing the eye, which traps the burning agent against the eye surface.
Emergency treatment for chemical exposure is to flush eyes immediately with either water or a prepared eye-flushing solution. The ANSI standard requires eyewashes be able to deliver 15 minutes of continual flushing to both eyes simultaneously at a minimum of 0.4 gpm. (Eye/face washes must deliver a minimum of 3.0 gpm.) It specifies tepid water for eye flushing, defined as being between 60° and 100° F. It requires eyewash stations to be located within ten seconds’ travel time from any location where exposure may occur. The equipment must be able to be activated within one second or less and must stay on without requiring use of the operator’s hands.
To ensure that eyewash is in working order when needed, it must be tested once per week. An eyewash station must be equipped with covers that prevent dust or debris from entering the spray heads (which point straight up), and the covers must remove automatically when the device is activated. This is usually accomplished with plastic dust caps that are popped off by the pressure of the activated wash.
These performance standards, with their emphasis on time and ease of operation, suggest other considerations for the designer. The eyewash station should be placed where a person in mid-emergency will find it easily. It must be operable without inducing mistakes or confusion in a moment of crisis. The flushing action should be effective but comfortable (such as is achieved by aerated spray heads) to encourage using it for the extended flushing period that’s recommended. It should be easy to test, simplifying compliance with the testing requirements.
Examples of locations where exposure may be expected to occur include any lab handling fluids or powders of an alkaline or acidic nature, areas where medically contaminated substances are handled and maintenance areas or closets where cleaning products are mixed or dumped.
The real world
The unfortunate truth is real-world eyewash installations often fall short of these safety goals. In many labs, the eyewash station is not well located, not well marked and difficult to find. Moreover, a free-standing station requires a bucket (and probably additional cleanup) for weekly testing, which may deter testing from being performed as often as required.
An attempt to improve this situation was made with the introduction of faucet-mount devices that attach to existing faucets. This places eyewash stations in locations where people will reflexively turn in an emergency: the sink. It saves money because the unit does not have to be individually plumbed in. It saves space along the walls where a freestanding station would mount and on the floor where space must be left for the eye injury victim to stand. It also makes it quick and easy to test, because the sink catches the water.
However, add-on devices pose safety challenges in actual installations. Because they are dependent on the operation of the faucet’s hot and cold valves, there is always the potential an injured person could activate the hot instead of the cold, presenting a scalding danger. To remedy this, users are often advised to make the eyewash the primary function of the device and disable the hot supply. This configuration limits the utility of the faucet because hot water for washing has been eliminated and faucet operation has become secondary.
Dedicated combination units
A newer improvement over add-on devices are dedicated dual-function faucet/eyewash units. These are standard laboratory faucets with built in, independently operating eyewash stations. They use a standard plumbing supply, but eyewash function is controlled without use of the faucet valves and is activated by a single pull on a dedicated, well-marked lever. They comply with the ANSI standard and are made in a variety of configurations for different sink types.
A key benefit of the dual-function approach is the independent water supply to the eyewash function, so there is never a danger of hot water being delivered for eye flushing. This independent supply can either be from a specially controlled tepid water source or from the cold water inlet if it meets the temperature requirements. In circumstances where the chemical reaction of the expected exposure is accelerated by flushing fluid temperature, a medical advisor or industrial hygienist should be consulted about optimum temperature for the application.
From a design perspective, combination units have all the virtues of faucet-mount add-ons: they take no additional space, require no additional location to be plumbed and have the benefit of a sink to catch water in testing and in use.
From a safety perspective, they resolve the negative issues of faucet mounts, because they are functionally equivalent to a dedicated eyewash station. They may improve overall safety versus a free-standing station by avoiding the creation of slippery floors around the station when the eyewash is in use. The newest dual-function units also offer aesthetic improvements over more traditional lab-style faucets, which may be more compatible with contemporary design.
Case Study: Veteran’s Administration Hospital, Minneapolis
In 2009, the Veteran’s Administration (VA) Hospital in Minneapolis ordered an upgrade of all their eyewashes and drench showers. The four-story, 1.5 million-square foot facility, completed in the late 1980s, includes numerous laboratory facilities. The upgrade was needed to meet the newer requirements for tepid water flushing. The existing eyewashes were not plumbed for tepid water. Many were faucet-mounted adaptations using the hospital’s cold-water supply.
Dual-function eyewash/faucets were selected to replace existing faucets in a variety of configurations. Counter-mounted units included both 5- and 8-in. high goosenecks, some with dual handles and some with single-lever controls for the faucet functions. Wall mounted units, where both valves and faucet neck protrude horizontally from the wall above the sink, were also required in some locations. Some even had foot-pedal operation for the faucet function. In some instances, where the same manufacturer as the new dual-function unit made the existing faucet, they were able to replace the faucet neck with a dual-function neck, reducing materials and plumbing costs.
In addition to 128 faucet/eyewash dual-function units, emergency swing-out and swing-down eyewashes were installed in some locations. Free-standing emergency shower/eyewash combination units were also installed. In areas where the building’s hot water supply could not reliably deliver tepid water as required, heaters were added. Thermostatic mixing valves control temperature for the tepid water supplies.
Curt Wentz of Wentz Associates in Minneapolis noted a significant factor in the selection of the dual-function units was “the flexibility to use the fixture for normal washing and for emergencies.”
Pamela Russell Demaster, occupational safety manager for the hospital, said, “People should be wearing their personal protective equipment, specifically proper eye protection, if they’re following the applicable OSHA safety standards, but it would be terrible if someone were exposed and there was no functioning eyewash.”
Imants Stiebris, BS, MBA, is Director of Global Safety Sales for Speakman Company, a 143-year-old, family-owned business that is an industry leader in design and manufacture of plumbing fixtures for safety applications. Stiebris is chairman of the International Safety Equipment Association’s (ISEA) ANSI Z358.1 Shower & Eyewash Product Group (the body responsible for maintaining and publishing the standard), and was a member of the organization’s board of trustees from 2004–2007. Steven H. Miller, CDT, is an award-winning writer and photographer, and a marketing consultant specializing in issues of the construction industry.
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