"subject to evaporation"

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Raanne

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Can anyone provide some help with a code interpretation? I have an owner fighting me on trap primers, saying that they only want to install them where it would cause an "undetected IAQ risk" - the actual code just says to provide them where traps are "subject to evaporation"... I have them on all of my floor drains, but am beign given the directive to take them off.

Has anyone run into this before? how do you normally deal with it?

:mad:

 
I have no idea how to do that officially. But I can tell you, as a homeowner with floor drains that do not have trap primers, I need to pour water into them once about every 2-3 weeks, depending on the weather (wind across the vent stacks seems to dry them out even faster). I know when it's time to "feed" them because the house smells like the septic tank. It's awful, and I wish I had spent the money on the trap primers.

 
Depending on where you are trap primers may be required by code. I know 2003 IPC and later requires traps be protected from evaporation.

The issue your owner is facing is maintenence. The problem with trap primers is that they all eventually fail, and are usually abandoned afterward. Then the money you spent for trap primers is wasted.

His headache may have come from a particular trap primer - and you may be able to reccommend an alternative. See this article for more info: http://psdmagazine.org/ASPE_memberpdf/May_Jun_05/52_53.pdf

One other alternative is to look at a mechanical trap. One I know of is www.trapguard.com. There are others as well. I have not used them and therefore cannot give them an endorsement. I would check it out though.

My final advice is to not push your owner too hard on the subject. If the area is likely to stay wet (regular cleanup, etc) then I would not install a trap primer but would note that traps must be checked for proper seal by maintenence staff on a regular basis. If it is in a space that is likely to dry out then consider the trapguard or other like system - or talk to your owner about adding a trap primer there.

 
Agreed with Dleg. In our plant, it happens about once every month through the winter months in about 6 different floor drain locations. People complain about sewer smell. I ask them to take a bucket of water and pour down the drain. Wa-lah. Problem fixed, but it's just a factor of life that repeats itself every year. I guess those 6 locations are the one's that we should have considered are "high evaporation areas"... Maintenance shop gets swept and not mopped, therefore 2 drains in it dry out.

 
Agreed with Dleg. In our plant, it happens about once every month through the winter months in about 6 different floor drain locations. People complain about sewer smell. I ask them to take a bucket of water and pour down the drain. Wa-lah. Problem fixed, but it's just a factor of life that repeats itself every year. I guess those 6 locations are the one's that we should have considered are "high evaporation areas"... Maintenance shop gets swept and not mopped, therefore 2 drains in it dry out.
Try pouring a couple cups of vegatable oil in after re-filling with water....problem solved.

 
Try pouring a couple cups of vegatable oil in after re-filling with water....problem solved.
In some cases you actually want to use a light mineral oil instead of a veggie oil. The veggie can go rancid, and also will gel if lower temperatures are present. Typically mineral oil will stay liquid at lower temps, and will not go rancid.

I believe its the NPC that states that you have to use a trap primer or a deep seal trap. The deep seal can still go dry, but it just takes lots longer to do so...

 
In some cases you actually want to use a light mineral oil instead of a veggie oil. The veggie can go rancid, and also will gel if lower temperatures are present. Typically mineral oil will stay liquid at lower temps, and will not go rancid.
The only problem with that is that it would violate your local sewer code.... or septic system regs, if connected to one. Can't put mineral oil into a sewer. Veggie oil is probably also not technically allowable, but at least it won't show up in the effluent monitoring. The light mineral oil would probably also make the bathroom smell like a garage.

Really, the best answer is the trap primer. Short of that, putting water into it regularly will solve the problem and hurt nothing.

 
The only problem with that is that it would violate your local sewer code.... or septic system regs, if connected to one. Can't put mineral oil into a sewer. Veggie oil is probably also not technically allowable, but at least it won't show up in the effluent monitoring. The light mineral oil would probably also make the bathroom smell like a garage.
Really, the best answer is the trap primer. Short of that, putting water into it regularly will solve the problem and hurt nothing.
What about that stuff they use for waterless urinals? Urine and water go through, odors stay out, "stuff" stays in place. Zero evaporation, low freezing. It's perfect!

Dleg, get some waterless urinal, wizz flowing, stink stopping stuff!

 
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