HEALTH AND SANITATION
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these notices are issued as a precaution, but others
are originated based on known events. When there is
a boil water notice in a certain area, the corresponding
consumers have two options: boiling all the water used
at home or installing a microbiological water treatment
system, such as the ones that have been mentioned.
To select the best system according to one’s needs, it
is very important to keep in mind that systems have to
pass certain certifications to be considered capable of
removing microbiological contaminants. With that said,
there are two useful tools available: the United States
Environmental Protection Agency’s Guide Standard for
Microbiological Water Purifiers (sometimes referred to
as “the Guide Standard”) and the P-231 protocol, which
is more recent. The difference between them is that the
Guide Standard is recommended for testing units used
for treating water that may be microbiologically unsafe or
is of unknown quality, while the P-231 protocol is used
29
for testing units meant for the supplemental treatment of
water deemed to be microbiologically safe.
Therefore, any system that is certified through either
protocol is considered a system that would provide
microbiological protection to the consumer. To be
completely sure that a certain system is properly
certified, the consumer should check on the appropriate
agency websites that provide a list of certified systems.
In conclusion, electropositive filters provide an easy and
efficient solution for the filtration of broad spectrum
contaminants, including the removal of microorganisms.
Pathogens are considered to be very aggressive
contaminants and their removal is of great interest to the
consumer. Identifying the most suitable system for everyone’s
needs is challenging, but that problem can be overcome by
providing literature that educates the general population, thus
resulting in a more informed decision. PA
There are two
main types
of separation
mec hanism:
sieve
retention and
adsorption.
Operational conditions and water
quality through superheat-and-flush
disinfection in legionella control
The superheat-and-flush disinfection method involves raising
the water temperature in the hot water heater sufficiently to
ensure hot water is delivered to all outlets.
By Environmental Protection Agency, document EPA 810-R-16-001
Flushing involves hot water passing throughout the
system and outlets for a suitable period. In building
water systems that are not heavily contaminated, a
www.plumbingafrica.co.za
constant hot water heater temperature of 60 degrees
C (and 55 degrees at the outlets) is often enough to
control but not necessarily eliminate legionella.
Continued on page 31 >>
April 2018 Volume 24 I Number 2