For more general design and construction requirements that pertain to all pools, see WAC 246-260-031
(1) Walking surface. A minimum four-foot wide walking surface shall extend around the perimeter of a spray feature sufficient that the spray will not exceed the walkway area in normal conditions including light wind conditions.
(2) Pool structure. Owners shall ensure each spray pool has:
(a) Pool surfaces with nonslip finishes impervious to water;
(b) Uniform pool floor slopes not exceeding one foot of a slope for every twelve feet of horizontal floor length;
(c) A source of water for the spray feature from an approved potable water supply;
(d) Water drained to waste disposed in a manner approved by local authorities or the department after use in the spray pool, unless it is recirculated with approved treatment as described in WAC 246-260-031
(e) The entire volume of water circulated through an approved treatment system every thirty minutes or less if water is recirculated.
(3) Inlets. Owners shall ensure spray nozzles at each spray pool are designed and maintained to not inflict physical damage to bathers. Design and construction shall include evaluation of forces of the spray nozzle including velocity, pressure and total force in proximity to bathers' eyes and other body orifices.
(a) Owners shall ensure outlet drains are designed and maintained to provide sufficient capacity to prohibit water accumulation in each spray pool.
(b) Piping must be designed so velocity in piping assuming one hundred percent of the pump recirculation flow does not exceed six fps between the pump and the outlet drain.
(c) Each spray pool must have two or more outlet drains that:
(i) Are located at the low point of the pool;
(ii) Are located at least three feet apart, measured between the centers of the drain covers; and
(iii) Are manifolded with junction fittings placed in the middle of branch line piping between outlet drains, so that the length of branch line piping is equal on each side of the junction fitting, see Figure 081.1;
Outlet Drain Branch Line Piping Detail
(iv) Have drain covers removable only with specific tools.
(d) Multiple outlet drains must be designed so that if one outlet drain becomes blocked, the remaining outlet drains are rated to at least one hundred percent of the maximum pump flow; see Table 081.1.
Outlet Drain Flow Rating Requirements
Number of Outlet Drains per Recirculation System
Outlet drain rated flow capacity must be at least equal to the percent of maximum pump flow indicated, depending on the number of outlet drains.
(e) Outlet drains that are accessible to pool users and submerged must:
(i) Conform to the suction fitting standard; and
(ii) Have a maximum flow of one and one-half feet per second through the cover.
(f) Outlet drains that are accessible to pool users and not submerged must have:
(i) Openings that prevent the passage of a sphere over one-half inch in diameter; and
(ii) Drain covers that withstand forces of users.
(5) Emergency equipment. No later than June 1, 2008, owners of existing pools with single main drains shall install emergency equipment to shut off all pumps hooked to the recirculation lines for the pools. This emergency equipment must be placed within twenty feet of the pool and marked with an emergency shutoff sign. The shutoff switch must include an audible alarm which can be heard by those in the area, or the switch must have an alarm that goes to a point where staff is always present during the periods the pool is open.
(a) Pools that include dual main drains meeting the requirements of this section, or other acceptable methods of providing equivalent protection to the emergency shutoff switch, are exempt from this requirement.
(b) The owner shall check the shutoff switch at least twice annually to determine it is properly operating.
(c) The department will develop a guidance document to aid owners and designers in potential options to the emergency shutoff switch and audible alarm.