Steel is the most common material for spring washers due to its ease of process and its high tensile strength. Chrome vandium alloy is a higher quality steel with a good through-hardening capability; it is used to make very thick spring washers.
How to Prevent Swimmerâs Itch. Thereâs no cure-all to eliminate swimmerâs itch. The negative symptoms are, ironically, a problem of our own immune systemâs making, and short of abstaining from swimming altogether, thereâs a risk of getting swimmerâs itch in a Northern Michigan lake.
Children who swim are exposed to a host of pathogenic germs, and babies in particular tend to swallow the water theyâre swimming in. Also, water that is too cold is not good for babies, Gilchrist says. âYou have to watch out for hypothermia.â. Class size and level of supervision also is important.