Determining what type of wash is needed in an eye emergency
Answered by Casey Hayes, director of engineering, Haws Corp., Sparks, NV.
Yes. The various commercially available emergency eyewashes, eye/face washes and drench showers provide a wide range of features and general capabilities. Recognizing that certain families of products are appropriate for specific applications, specifiers should begin by considering the injury risks inherent in their operations or areas of operation. Using the applicable ANSI and other standards, the number of installations and general locations can be determined.
Next, using the already established risks as a guide, one can determine relatively easily the proper family of products, such as eyewashes versus eye/face washes. The main idea is to establish the risk and then select the product type that addresses that risk. For instance, if the risk is limited to potential airborne particulate matter becoming lodged in a worker's eyes, an eyewash is sufficient. If, however, the risk involves possible splashing of acids, or caustic or base materials that could come into contact with the eyes and face, an eye/face wash is indicated. Overspecifying products based on potential risks can be a significant waste of resources, while underspecifying can result in less than adequate emergency response. Weighing your risks against the capabilities of a specific family of products provides definitive direction on product selection.
With respect to specific features needed, specifiers should realize there is an absolute relationship between the cost of the emergency response products selected and the features provided. For instance, features like flow controls, while not required by ANSI Z358.1, offer improved operation by minimizing the impact of variations in input-line pressure on the outlet pressures and flow patterns of emergency equipment. This improved operation translates into greater comfort for the accident victim during use, thereby minimizing the possibility that the victim will cut the use cycle short of the required 15-minute length. Likewise, other premium features such as diffused flow eyewash and eye/face wash heads, eyewash and eye/face wash foot treadle actuators, and stainless steel stems in ball valves add tremendously to the value, longevity and "user-friendliness" of the equipment.
Maintenance also should be considered in specific product selection. For instance, in corrosive environments, the use of stainless steel components is obviously of great importance. Also, the availability of covers over the spray heads or covering the entire eyewash or eye/face wash might be in order in dusty environments.
Finally, specifiers should consider installation in their choice of equipment. Products that are factory preassembled and pressure tested are easier to install and less likely to experience leaks and other problems sometimes encountered at installation.