Which step should be completed before reopening after a solid stool/vomit incident?

• A. Confirm water chemistry is within parameters
• B. Open pool
• C. Raise FAC to 2 ppm and maintain pH <= 7.5 for 25-30 minutes
• D. Backwash the filter

Answer: (A)

After a solid stool or vomit incident, the priority is to ensure the water is safe for swimmers before reopening. The best step is to verify that water chemistry is within safe parameters—checking that the free chlorine residual, pH, alkalinity, and combined chlorine are all in the acceptable ranges and stable. This confirms the disinfection system is effectively in place and that the environment won’t irritate eyes or skin or harbor pathogens. Other actions, like simply opening the pool, applying a brief chlorine boost, or backwashing the filter, are part of the cleanup process but do not by themselves guarantee safety for reopening. Verifying the chemistry first ensures you’re reopening only when the water meets safety standards.