The types of equipment addressed by the ANSI standard include:
Emergency shower. The emergency shower is "a unit that enables a user to have water cascading over the entire body." This unit is used for general irrigation of the body and although it can be used to rinse, the unit is not meant for flushing of the eyes.
Eyewash. The eyewash is a unit that supplies fluid to irrigate and flush the eyes.
Personal eyewash. The personal eyewash is "a supplementary eyewash that supports plumbed units, self-contained units, or both by delivering immediate flushing for less than 15 minutes." The major difference between self-contained or plumbed and personal eyewash equipment is that the self-contained or plumbed one must have at least a 15-minute supply of water while the personal units have less than a 15-minute supply. Because of this, the personal eyewash is used on the site for immediate flushing and while the victim is moved to another unit. Irrigation should continue once the victim reaches the other unit.
Eye/face wash. This devise is "used to irrigate and flush both the face and the eyes."
Hand-held drench hose. This combination unit combines a shower with an eyewash or eye/face wash, or with a drench hose, or with both into one assembly.
Combination unit. The combination unit combines a shower with an eyewash or eye/face wash, or with a drench hose, or with both into one assembly.
Plumbed unit. A plumbed unit is permanently connected to a portable water source.
Self-contained unit. A self-contained unit is not permanently installed and must be refilled or replaced after use.
In general, the type of hazard and the number and availability of personal help to determine what type of emergency equipment to install. The most commonly used emergency wash equipment is the overhead deluge shower, the combination deluge shower with multiple-spray unites, and the complete multiple-spray decontamination unit.
Radioactive or highly toxic materials may require a total decontamination shower. These are booth-type showers with numerous spray nozzles that may be combined with central overhead sprayers. A complete safety station combines the eye/face wash fountain with a drench shower. A very useful addition to an eyewash fountain is a face spray ring that sprays the face gently to remove contaminants.
A laboratory safety shower does not always give the same drenching effect of the standard overhead shower. Because of the type of shower head and the angle the water falls, the person using a laboratory safety shower must turn and strain to make sure all chemicals are washed away. This type of shower is suitable where the upper front portion of the body is exposed to chemicals (such as bench work in a laboratory). Even then, the overhead shower should be considered as a backup precaution. The drench shower is not suitable for washing out the eyes because too much water is flowing downward making it difficult to position the face under the shower.
