LaMotte Pool Manager Water Quality Handbook User Manual
Page 27
“Shocking” the Pool
Pool water that contains combined chlorine
(chloramines) and other organic contaminants such as
deodorants and lotions must be treated to keep the
water clear and sanitary. There are two primary
treatment processes for “shocking” pool and spa water:
1.
Use a liquid or granular chlorine compound in a
concentrated or excessive amount to increase the
free chlorine to a level high enough to break down
the undesirable chloramines and organics. In most
cases, the chlorine level is raised to 10 ppm (about 5
times the normal level). Following a high chlorine
shock treatment, the pool is often closed for 6-12
hours to allow chlorine levels to return to normal. 4
ppm is considered a safe concentration for re-entry
into the pool.
2.
“Non-chlorine” shock is a chlorine-free
persulfate-based compound which is designed to
eliminate undesirable combined chlorine. This type
of treatment has the unique advantage of allowing
bathers to return to the pool shortly after use.
Fecal, vomit or blood accidents
If fecal matter, vomit or blood enters the water,
immediately evacuate the pool and remove as much of
the material as possible. The pool should then be closed
and treated with at least 10 ppm chlorine. Pool
managers should train all personnel on the guidelines for
treating such accidents. These may be obtained from
local health officials or from the Center for Disease
Control website (www.cdc.gov/healthy swimming).
A note about superchlorination
Some organic chlorine cannot be oxidized by shock or
superchlorination. These are sometimes referred to as
nuisance compounds. Usually the concentration of
these is very minimal, but they do contribute to the
combined chlorine reading.
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