Emergency showers and eye-wash units?

We have emergency shower/eyewash combination units in our plant. The units are not used that much. I have heard that the Legionella thrive in cooler water. Is this true and what measures can we take to combat the problem? The emergency shower/eyewash units are fed from the general potable water supply but are deadlegs as far as general system flow patterns.

 

It is possible that Legionella might be in these units, but the risk is negligible, and no infections have even been reported to occur from use of these units. No guidelines have ever been issued for such units and are probably unnecessary.