Instantaneous bather load reduction for low turnover rate

[Neil Ballard]

I am reading the pwtag code of practice I am trying to calculate instantaneous bather load as our circulation rate is low but the formula is not laid out clearly. The calculation is either:

pool volume
________________________
(turnover period x 1.7)

or

Pool volume
_________________ x 1.7
turnover period

can you tell me which is correct?

Many thanks,
Neil Ballard

• This topic was modified 3 years, 6 months ago by Neil Ballard.

[Stockwell Safety]

Hi Neil,

The instantaneous bather load calculation is:

Water depth Maximum bathing load
< 1.0m 1 bather per 2.2m2 1.0 m to 1.5m 1 bather per 2.7m2 > 1.5m 1 bather per 4.0m2

The circulation rate calculation is:

Maximum bathing load x 1.7

Does that help?

[Neil Ballard]

Thanks for your reply but no it doesn’t answer my question. I need to calculate the reduced Instantaneous Bather load as per the PWTAG Code of practice page 18 because our circulation rate is lower than recommended. On that page they print the calculation but it is not very clearly laid out and it is hard to tell whether you multiply or divide by the factor of 1.7. That is my question.

[Stockwell Safety]

I see. It’s the top calculation in your initial post. Multiply whatever your turnover is by 1.7. Whatever that number is is what you divide the water volume by.

[Neil Ballard]

Great, thanks for that.
I did the calculation another way (reducing the Max Bather Load by the same percentage as my actual flow rate was slower than that calculated by the (Maximum Bathing load x 1.7)formula above) and came to that conclusion as the two results were similar but I’m happy you’ve confirmed it for me.
They really ought to extend that division bar over the x 1.7 in their text to make it clear!

[Author]

Posts