This module examines the current
standards for microbiological
testing, and the interpretation of
results. Any actions always have to be
the responsibility of the operator, so
this advice can be invaluable.
In this Module we will be focusing on:
• Other Harmful Organisms found in
• Bacterial Sampling
• Microbiological Testing
• Dealing with Unsatisfactory Results
Some of the other harmful organisms that can be
found in swimming pools, include:-
This is a parasitic virus that can be passed from
human to human, in water.
Its symptoms range from a mild ear ache or
infection, respiratory difficulties, or to a very
distressing rash that can affect any part of the
It is easily destroyed by good disinfection, and so
its presence indicates ‘poor’ disinfection.
It is also one of the prescribed tests of a
This is a virus that is transmitted in water
vapour, and sprays.
The effect is to the respiratory system, and
can prove to be fatal in certain
The virus itself, enjoys conditions between
20 C and 60 C , in stored water areas.
These include circulation dead-
legs, standing water, etc. such as showers;
spas; air-conditioning units; etc.
An ideal breeding ground for disease?
• What about showers, wash-basins, etc?
• Is there a Legionella Risk Assessment!
In order to ensure compliance with H & S
legislation, bacteriological sampling is required:
The responsibility for monitoring compliance with health
and safety legislation at swimming pools falls to either
the HSE or the local authority Environmental Health
Departments (EHDs) depending upon the main activity
of the premises.
Pools in educational establishments or pools controlled
by a Local Authority are enforced by the Health &
Safety Executive (HSE). Private pools, for example
those in hotels, are the responsibility of EHDs.
However, it is the pool manager/operator who is
RESPONSIBLE FOR ENSURING THAT
MICROBIOLOGICAL TESTING IS CARRIED OUT
Environmental Health Officers have right of entry
into all pools under the Environmental Protection
Act 1990 and therefore may undertake
bacteriological sampling if they deem it necessary
Bacteriological sampling should be undertaken
monthly as a constant check to ensure the
bacteriological quality of a well run pool with the
correct disinfection levels and pH value.
Hydrotherapy pools should be sampled
More frequent samples are necessary where a
deterioration in water quality occurs.
Samples of pool
water are incubated
on an Agar
Medium, for 24 hours
at 37 C
Plate (Aerobic Colony) Count:
a sample of water is incubated for 24 hours
at 37 C, to indicate the total number of
no more than 10cfu/ml
(colony forming units)
- causes skin and ear infections (folliculitis)
- they multiply in poorly disinfected areas
- they can be found in spa pools, and where
there is poor filter maintenance
Faecal Coliforms (Escheria type 0157):
- indicates the presence of faecal cysts
that cannot be destroyed by chlorine
- it can be PATHOGENIC
- it inhabits the intestinal tract of
Dealing with Unsatisfactory Results.
You must arrange to………….
Take another microbiological test immediately
Take chemical tests, on the poolside, and
compare with laboratory test results
Review maintenance and pool water testing
and recording processes,
If the second microbiological test is unsatisfactory
An investigation into the management and
operating conditions of the pool can be
undertaken with the Health authority;
Environmental Health Dept., and other
The pool can be closed until all parties are
satisfied with the
Carlton Associates Ltd (c) 2013
That is the end of Module 5
What you need to do now:
1. Return to the course page
2. Download the module update notes and save them
on your computer
3. Read through the notes
4. Print out the notes and insert them in your manual
Carlton Associates Ltd (c) 2013
End of Module 5 Presentation