A spa shall be operated in a safe, sanitary manner and shall meet the following operational standards.
Table 12
Preferred Operating Range | Acceptable Operating Range | ||||
ORP (mV) | Free Cl (ppm) | Total Br (ppm) | ORP (mV) | Free Cl (ppm) | Total Br (ppm) |
700-880 | 2.0-8.0 | 4.0-18.0 | 700-880 | 1.0-1.8 | 2.0-3.5 |
650-700# | 2.0-8.0 | 4.0-18.0 | |||
650-700[DAGGER] | 8.2-10.0 | 18.5-22.0 |
#If these conditions occur on any 3 consecutive days or on any 5 days within a 7-day period, and the conditions reoccur after the spa is drained and cleaned, the facility management shall evaluate water parameters including, but not limited to, cyanuric acid, pH, combined chlorine, and phosphates (ortho- and total); and other conditions at the spa. The facility management shall modify parameters and conditions as practical to bring the ORP to a minimum of 700 mV. The evaluation shall be completed within 30 days after the low ORP condition is known to the facility management. A written report of the evaluation shall be kept with the spa records.
[DAGGER]If these conditions occur on any 2 consecutive days or on any 4 days within a 7-day period, the facility management shall drain and clean the spa and notify the inspection agency. If the conditions reoccur after the spa is drained and cleaned, the facility management shall cause the conditions at the spa specified in the previous footnote and the function of the ORP equipment to be investigated by a professional pool service company. A written report detailing source water parameters, spa water parameters, spa design (including information about the installed mechanical and chemical equipment), other conditions affecting the disinfectant concentration and the ORP, and the actions taken to increase ORP relative to the disinfectant residual shall be submitted to the local inspection agency within 30 days after the low ORP condition is known to the facility management.
The spa may reopen when no coliform or Pseudomonas aeruginosa bacteria are detected in a spa water sample taken when the spa water meets the requirements of paragraphs "a," "b" and "c" above.
If the spa is equipped with an automatic controller with a readout or local printout of ORP complying with the requirements of 15.51(2)"f" (4), the operator may make visual readings of ORP in lieu of manual testing, but the spa water shall be tested manually for disinfectant residual at least twice per day. Both ORP and disinfectant residual shall be recorded when manual testing is done. The operator shall specify in the spa records which results are from the manual tests.
If the spa is equipped with an automatic controller with a readout or local printout of pH complying with the requirements of 15.51(2)"f" (5), the operator may make visual readings of pH in lieu of manual testing, but the spa water shall be tested manually for pH at least twice per day. The operator shall specify in the spa records which results are from the manual tests.
The department may permit a longer period between refills for spas over 2000 gal upon evaluation of the use of the spa. Such permission shall be in writing, and a copy shall be available to an inspector upon request.
The maximum system flow rate is the design flow rate for the pump(s) directly connected to the outlet(s) in an outlet system. In the absence of better information, the maximum system flow rate is the capacity of the pump(s) at 50 feet TDH, based on the manufacturer's published pump curves.
If a spa has two or more fully submerged outlets on a single surface that are all less than 3 ft apart on center, are not unblockable, and are directly connected to a pump, the spa is considered to have a single fully submerged outlet.
If the department approves the application to disable the outlet, the outlet valve shall be closed and the valve secured by removing the handle, by locking the handle closed, or by another method approved by the department. The outlet may be physically disconnected from the pump system at the option of the facility management.
Iowa Admin. Code r. 641-15.51