Hot tubs and
Legionella
(Private, residential hot tubs)
• Purchase a spa test kit capable of checking free
chlorine levels
• Use the kit to check the disinfectant and pH levels
before each use
• Maintain disinfectant levels: chlorine at 3ppm
and bromine at 5ppm.Maintain the pH of water
between 7.2 and 7.8
• Superchlorinate (shock) the hot tub regularly using
chlorine. Become familiar with the hot tub shock
process by consulting your manual or spa/pool
supply store
• Drain and clean the hot tub after shocking
• Clean the hot tub by vigorously scrubbing
all surfaces with a chlorine solution such as
household bleach, to remove any biofilm or slime.
Biofilm protects bacteria from disinfectants. Rinse
the tub after cleaning
• Clean or replace filters according to your hot tub
instruction manual
• Refill hot tub and do not use until all chemical
levels have returned to normal
• Ensure your hot tub circulates the water
periodically when it is not in use. This is vital to
help prevent contamination of hot tub pipes with
disease causing organisms
Maintaining the proper disinfectant and pH levels in your hot
tub will prevent the growth and spread of bacteria, parasites
and viruses. These germs can cause skin, eye, ear, stomach or
respiratory illnesses, such as Legionnaires’ Disease, which is a
potentially fatal pneumonia. Legionella bacteria are naturally
present in water and soil, and can get into your hot tub via
improper maintenance or tracked-in dirt. If Legionella bacteria
are present in a poorly maintained hot tub they can grow and
be inhaled through the fine water spray or mist and can cause
Legionnaires’ Disease. Legionella grows best between
20°C–46°C or 68°C–113°F. Please see manufacturers’
recommendations for appropriate water temperatures for your
hot tub.
Follow the safety tips on this sheet to reduce your risk of illness
and increase your level of fun and enjoyment from your hot tub.
Note: This
information only
applies to private
residential hot
tubs.
For commercial hot
tub guidelines, consult
ASHRAE Guideline 12-2000
Adapted with permission of the City of Hamilton Public Health Services.
This document is available in accessible formats upon request.
Region of Waterloo Public Health
Health Protection and Investigation
www.regionofwaterloo.ca/ph
n
519-575-4400
n
TTY 519-575-4608
n
Fax 519-883-2241
1681037 (08/14)
HOT TUB SAFETY TIPS
Hot tubs are a lot of fun, but they can also become a
source of illness. Good hot tub maintenance is vital to
prevent infections.