PEOPLE | CULTURE | HAPPENINGS
SWIMMING
may be
one of the
most popu-lar
leisure
activities in this country.
There are roughly 10.4
million residential swim-ming
pools and 390,000
community pools in the
United States today, says
the Pool and Hot Tub
Alliance. Of these millions
of pools, about 35 percent
are saltwater, claims pool
supply company Hayward
Industries. The rest are
traditional chlorine.
With the summer tem-peratures
reaching 100
trending
Pool Water 101
Chlorine vs. Salt
BY LAUREN SEARS AND MELISSA SUTTON-SENG
degrees, it’s good to know
what you’re diving into to cool down.
What we think of as traditional chlorine pools have been
around since 1911, according to chemist Kevin Olsen, who
wrote an academic paper on the history of swimming pools.
In recent years, there has been an uptick in the installation of
saltwater pools, largely due to popular demand fueled by per-ceptions
about cleanliness and ease of maintenance. Saltwater
pool sanitation was developed in the late 1960s and early ’70s
by a retired chemistry professor. These pools began growing
in popularity in the ’80s and reached a new peak last year. So,
what’s the difference between the two?
Chlorine is a naturally occurring chemical element often
used as an antiseptic in drinking water, pool water and many
industrial production processes. When used to treat swimming
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WBM august 2019
pools, it acts as a sanitiz-ing
agent to keep harmful
bacteria out of the water.
It must be carefully reg-ulated
using testing strips
and additional chemicals
in order to keep bacteria
at bay and pH at proper
levels. When chlorine
mixes with urine — as
happens often in swim-ming
pools — the chemi-cal
interaction generates
chloramines, chemical
compounds that can irri-tate
skin, eyes and even
the respiratory tract. On
the plus side, equipment
maintenance on chlorine
pools is said to be very
low, and chlorine won’t
cause corrosion as often occurs with saltwater pools.
Most people believe that saltwater pools are just that — salt-water.
In fact, saltwater pools contain chlorine, too. In saltwater
pools, the chlorine is generated from salt through a process
called electrolysis. This process produces just enough chlorine
to sanitize the pool and does so continually, in contrast to the
infusions of chlorine poured into traditional pools. Far from
being salty like seawater, the salinity of saltwater pools is only
about one-tenth that of the ocean — closer to the salinity of a
teardrop.
Saltwater pools are often portrayed as being less harsh on
your skin and eyes than chlorinated pools, but there really isn’t
much evidence to support this claim other than pool-goer
experience.
july 2019
WILL JONES