PARK SANITATION 



891 



Swimming Pool Sanitation. 



The public swimming pool has no equal as a form of recreation, and 

 in season enjoys a heavy patronage. It is likewise true that the swimming 

 pool can boast no equal as a medium for the spread of certain communi- 

 cable diseases amongst its patrons unless it be operated under definite 

 sanitary rules and regulations. The following sanitary regulations covering 

 swimming pools are based upon general recommendations proposed by the 

 Committee on Bathing Places during the 1925 Conference of State Sanitary 

 Engineers, the American Public Health Association and the American 

 Association for Promoting Hygiene and Public Baths. 



The factors to be considered in dealing with the swimming pool situ- 

 ation from a sanitary standpoint are: Bathing load limits, swimming pool 

 construction, maintenance, sanitary quality of swimming pool waters and 

 standard rules to be observed bv bathers. 



Bathing Load Limits. 



1. There should not be any basic difference in the 

 design of artificial indoor and outdoor pools, so far as 

 the design relates to the sanitation of the pool and 

 water. 



2. Bathing load limits will depend upon the following 

 conditions: 



A. Frequency of changing the water. (Fill and draw 

 pools.) The total number of bathers allowed to use the 

 pool during any period of time should not exceed twenty 

 persons per one thousand gallons of clean water. "Clean 

 water" is understood to mean new clean water used to 

 refill the pool, new clean water used to replace loss by 

 splashing or during cleaning, water taken from the pool 

 and returned after filtration, or any combination of such 

 waters. 



(i) Method of determining bathing load limit indi- 

 cated above. Assume a pool of 50,000 gallons. Also 

 assume water being withdrawn from the pool and re- 

 placed with new water or properly filtered water at the 

 rate of 2,000 gallons per hour. Under paragraph A the 

 volume of new, clean water being added would be suffi- 

 cient for 2 x 20 (40) persons per hour, or 400 persons 

 during a ten-hour bathing day. If the flowing through 

 or recirculating were continued throughout the 24 hours 

 with bathing limited to ten hours, there would be an 

 accumulation of 28,000 gallons of clean water during 

 the non-bathing period which would permit the use of 

 the pool by 28 x 20 (560) additional persons, or a total 

 of 400 plus 560 (960) persons during the ten-hour day. 



B. Frequency of disinfection. (Flowing through or 

 recirculation pools.) The total number of bathers 

 allowed to use the pool during any period of time 

 should not exceed seven persons per 1,000 gallons of 

 water in the pool, unless the pool shall have been 

 completely disinfected once during the period. "Com- 

 pletely disinfected" means that the method of disin- 



fection shall be such as to insure a bacterial quality of 

 water as prescribed under " Bacterial Quality of Water" 

 given below. 



(i) Methods of determining bathing load limit indi- 

 cated above. Assume a pool of 50,000 gallons. Fifty 

 by seven persons (350) may use pool after refilling be- 

 fore disinfection is required. After complete disinfec- 

 tion, 350 additional persons may use the pool, at which 

 time 350 plus 350 plus 300 persons (1,000 persons) will 

 have used the pool and the water must be replaced. 



3. An average of 35 square feet of space per adult 

 should be allowed at all times to prevent accidents 

 from overcrowding. 



4. The length of the bathing period may be regu- 

 lated by local conditions and preferences, there being 

 no apparent hygienic reason for placing a limit. 



5. The depth of water for diving may be safely 

 established as follows: (a) diving from water level, safe 

 depth is five feet, (b) Diving from an elevation of three 

 feet, safe depth is six feet, (c) Diving from an elevation 

 of six feet, safe depth is eight feet, (d) Diving from an 

 elevation of ten feet, safe depth is nine to ten feet. 



6. A ten-foot area surrounding the diving plank 

 should be sufficient protection for the diver. 



7. The number of persons allowed within the ten- 

 foot area at one time should not exceed three or four 

 at the time a diver is about to enter the water. 

 Standards for Swimming Pool Construction. 



1. The pool should be well lighted. 



2. The interior surface of the pool should present a 

 perfectly smooth surface, without cracks, crevices, 

 sharp corners, or pockets to shelter dirt and disease 

 germs. 



3. The pool should be surrounded by an overflow 

 trough, and the floor surrounding the pool should be 

 drained so that no water can flow from the floor into 

 the pool. 



