Chlorine/Trihalomethanes Odor Ventilation

[Loumolito]

I am a HVAC engineer working on an exhaust design project for a water treatment plant. The plant is having air quality issues with chlorine odor in the filter bed gallery. Workers at the plant are complaining about sore throats after a full day work.

We are planning on building enclosures to separate the open water beds from the plant floor.

My question: When we encapsulate the water filter beds, what issues may arise? What is the maximum exposure limits for humans when they enter the enclosure for maintenance?

I'm trying to determine an exhaust rate formula. I will try to get the levels of chlorine in the filter basins.

 

[gr2vessels]

I would try first with the good old google, download the chlorine MSDS. Then read it and set a level you feel acceptable (if you ask them, it will be 0 limit). I noticed some tendencies toward 0.06-0.1 ppm. The 0.1 ppm will still do damage to health, depending on exposure! Also, you should consider PPE for the people entering the encapsulated filter beds, it is cheaper to keep a few oxygen masks rather than running 24/7 an extraction system. Bonus will be no flies around the plant, ever.
Cheers,
gr2vessels