Shock chlorination is a process used in many swimming pools,
water wells,
springs
Spring(s) may refer to:
Common uses
* Spring (season), a season of the year
* Spring (device), a mechanical device that stores energy
* Spring (hydrology), a natural source of water
* Spring (mathematics), a geometric surface in the shape of a he ...
, and other water sources to reduce the
bacterial and
algal residue in the water. Shock chlorination is performed by mixing a large amount of
sodium hypochlorite, which can be in the form of a powder or a liquid such as
chlorine bleach, into the water. The common advice is that the amount added must raise the level of chlorine to 10X the level (in parts per million) of
chloramines present in the pool water; this is "shocking". A lesser ratio is termed superchlorinating.
Water that is being shock chlorinated should not be swum in or drunk until the sodium hypochlorite count in the water goes down to three
ppm or less. Commercial
sodium hypochlorite should not be mixed with commercial
calcium hypochlorite
Calcium hypochlorite is an inorganic compound with formula Ca(OCl)2. It is the main active ingredient of commercial products called bleaching powder, chlorine powder, or chlorinated lime, used for water treatment and as a bleaching agent. Thi ...
, as there is a risk of explosion. Although a verb for superchlorination,
"shock" is often misunderstood (through marketing and sales language) to be a unique type of product.
Drawbacks
While "shocking" pools to reduce the buildup of
chloramines works with inorganic, ammonia-based chloramines, in two studies it was found ineffective with the organic chloramines present in all pool water e.g. with
creatinine, an organic component in
human sweat
Perspiration, also known as sweating, is the production of fluids secreted by the sweat glands in the skin of mammals.
Two types of sweat glands can be found in humans: eccrine glands and apocrine glands. The eccrine sweat glands are distri ...
. Indeed, superchlorination produces free chlorine that reacts with organic contaminants to form a variety of
disinfection byproducts
Disinfection by-products (DBPs) result from chemical reactions between organic and inorganic matter in water with chemical treatment agents during the water disinfection process.
Chlorination disinfection byproducts
Chlorinated disinfection agen ...
(DBPs) which are hazardous to swimmer health e.g. one of the worst DBPs is the noxious and volatile
trichloramine (NCl
3), well known for irritating the eyes nearby a pool. It has been pointed out that
ozone is an excellent alternative, a much more effective oxidizer than chlorine shock.
See also
*
Water chlorination
References
{{DEFAULTSORT:Shock Chlorination
Water treatment
Chlorine