Light proofing exhaust fan

[high life 45]

Looikng to make a light trap/stop light leaks from a 12' max fan with the least amount of cfm loss possible..

The fan is between two flower rooms, sharing an ac.

I looked into dust shrooms but they are pretty expensive, but that might be the best route.
I would definitely need two, because I looked at one and it didn't quite do the trick...


Dark room vents seem like they would cut down on flow quite a bit....


Also can anyone can interpret this chart from can fans site? I am not sure what "wg" stands for?
Is it "static pressure" or inches of ducting or something like that?

Performance Data

|--------------------------- in. wg -----------------------------------------------------------|​

-----------0" -- .125" .25" .375" -.5"* .75"* 1.0" -1.25" 1.5"
CFM 8" - 667 --650 --630 -610 -585 -520 --420 - 150 -100
CFM 12" 1708 1680 1655 1630 1595 1530 1460 1380 1300

 

[the gnome]

when i looked to size a fan to the can 150 filter, wg.
I may be wrong on this BUT the way i think i understand it is...
its a measure of resistance against a fans pull.

i think the can filters run .75 wg
so by that chart the 12" max fan pulls 1708cfm not hooked to anything.
hooked to a filter rated @ .75 that fan is actually pulling 1530cfm when hooked tpo the filter.
X amount of feet of ducting also factors in,
even the type of ducting, like the smooth walled type gives less resistance as opposed to the flex duct.

somewhere i had a chart that showed how much length, what type and size of ducting and how many bends would create X amount of resistance so you can size a fan to it.

 

[high life 45]

thanx!

A filter is a good option.

Throw that chart up here if you can.

 

[high life 45]

This looks to be the best option.....
http://www.foreverflowering.net/breathable-wall-main

 

[forkup]

Nice find, kinda expensive but I can think of a lot of uses for it.