Description
Microbial Water Testing Analysis for Swimming Pools & Spas
From a microbiological perspective, there are two main sources of contamination in pools and spas.
- Bather derived microbes washed from the skin or present in body fluids discharged into the water.
- Environmental organisms growing in the pool, especially on surfaces as biofilm.
The appropriate guidance document for analysis on pools is published by The Pool Water Treatment Advisory Group (PWTAG).
It is likely the microbial challenge in colder swimming pools will be much lower than for a spa pool. Swimming pools and plunge pools normally have a lower microbial population than spa pools. However, both types of pool require microbiological monitoring to ensure they remain fit for continued use.
How often should you perform Swimming Pool testing?
Pools open to the public should be sampled monthly for hygiene with the addition of Legionella testing on Spa Pools quarterly
Private pools are sampled at the discretion of the owners but we strongly recommend the same sampling frequency.
Note. The presence of Pseudomonas aeruginosa in hot tubs can lead to cases of folliculitis a bumpy red rash on the skin as well as otitis media and otitis interna middle and inner ear infections.
Pool & Spa Hygiene Only Analysis includes:
- E. coli
- Total coliforms
- Pseudomonas aeruginosa
- *TVC/Aerobic colony count at 37C
Tests should be carried out monthly
This analysis omits Legionella as it is not required for Swimming Pools and is only needed quarterly in Spas.
Spa Pools & Warm Water
For obvious reasons, the likelihood of microbial issues in a Spa is much higher as the pools are at higher temperatures and are frequented much more often by bathers. This, in essence, creates an incubator for microbes to grow. The analysis for warm water pools differs from cold pools in that it is recommended to test for Legionella also.
Spa Hygiene & Legionella Analysis includes:
- E. coli
- Total coliforms
- Pseudomonas aeruginosa
- *TVC/Aerobic colony count at 37C
- Legionella
This test should substitute the Hygiene only analysis every 3 months so you can keep a log of both Hygiene & Legionella.
*TVC/Aerobic colony count is a basic measure of microbial loading in the water and very tight limits are set for this parameter.
Microbiological tests
Content from p48 of HSG 282 (Spa Pools)
157 The monitoring programme should include the routine monthly sampling and testing for the presence of bacteria and should include an ACC (or total viable or total colony count), coliforms, E coli, and P aeruginosa, in addition to quarterly tests for legionella.
158 The ACC will give an indication of the overall microbiological quality of the spa pool and whether microbiological control is being achieved. This should be carried out in accordance with BS EN ISO 622228 with incubation at 37 °C for 24 hours.
159 The presence of E coli and/or coliforms is an indication of the presence of serious contamination and a failure in the water treatment system to remove the contamination.
160 The presence of P aeruginosa is an indication of water treatment failure with likely colonisation of and biofilm formation on the spa-pool filter and within other parts of the system.
Download the full HSG 282 Spa Pool Guidance from the HSE here
Return Advice
We include a pre-paid Special Delivery mailbag with your packet, you must be able to get to a post office same day as sampling. If you know this isn’t possible, speak to us about our courier collection option (this is at extra charge).
To ensure the sample meets UKAS accreditation we must stress the customer take these steps in its return:
- Freeze gel packs overnight and place in the insulated box.
- Sample in the morning and take the packet to the Post Office before last collection.
This product requires insulated packaging to prevent the bacterial levels from changing in the post, the insulated packaging is therefore mandatory.
It is preferable the sample be taken and posted the same day to arrive within 24 hours to ensure accurate analysis. Samples can be taken Monday to Thursday but not Friday as the lab is not open weekends.
Sample pack contains:
- 1x 350ml sample bottle
- 1x return jiffy bag and pre-paid return label
- 1x Analysis sticker to be filled in
- Extra sample bottle for Legionella (if choosing spa analysis)
You will receive a sample pack in the post to take your water sample, you will then be able to return your sample with our prepaid postage label. The analysis takes from a couple of days for the Pseudomonas results and at least 10 days to confirm a negative Legionella result, a positive result will be reported as soon as observed.
Simple test kits for commonly used biocides are available.
Chemical products used in Spa Pool treatment.
