not be run routinely, but field kit testing for this purpose are available commercially.
Clarity of the pool water is ordinarily tested by visual inspection, but a 6-inch black disc
painted on a white background may be used. This device on the end of a stout cord is
thrown into the deep end of the pool and observed from the pool edge. Bacteriological
sampling, normally done at this time, is described in paragraph 1-19 of this lesson.
(3) Filter rooms. In this area, you will inspect the filtration, recirculation, and
disinfection equipment. Items of concern should be the hair strainer, the chlorinator,
and the chemical feed devices. At least once during the swimming season, and
preferably at the beginning, the filter surfaces should be inspected. Routine inspection
of the filters should include a check of the air release valves, flow rate indicators,
pressure gauges, and condition of piping and tanks. Each inspection of this area must
also include a review of all operational reports concerning the equipment. This often
proves to be a most valuable tool in gaining an insight into the causes of operational
(4) Summary and review of findings. You should make a summary of the
defective items in the space under remarks on the inspection report (see figure 1-7).
Refer to the items checked in the body of the report when you enter your remarks. In
this way, the installation authorities are instructed on details of the defect and may be
advised on how and when correction should be made. The report can be summarized
in the office on another checklist similar to the one shown in figure 1-7. It gives a
summary of the pool's operational conditions over a considerable period of time.
Another valuable office record is a tabulation of sampling results. With this form a
record may be kept of the chlorine, pH, and bacteriological sampling results from a pool
over an entire swimming season. This record by itself serves as one good measure of a
pool's operating efficiency.
1-19. BACTERIOLOGICAL STUDIES
a. Bacteriological Sampling of Pool Waters.
(1) Sample bottles. All sample bottles must be sterilized and treated with
sodium thiosulfate to reduce the chlorine present in the water at the moment the sample
is collected. If sodium thiosulfate were not used, the chlorine would act on the bacteria
in the sample while it was being held or transported.
Collection of samples.
(a) Time of collection. Samples should be collected when the pool is in
use and preferably during periods of heaviest swimmer load. You should vary the hour
of the day and the day of the week to obtain, over a period of time, a representative
cross section of the sanitary quality of the pool.