The Ultimate Odour Control Thread

haze010

Well-Known Member
Thank you for offering to help and indeed I do have a question regarding air exchange.
In the documentation you posted, they speak of ACH, air changes per hour.

I learned we need to change the air for plants every 5 minutes, so I need 12 ACH.
Is this correct or do you do otherwise?

Also, when calculating the fan's performance, how do you factor in the resistance of the carbon filter?
Again, I had picked up a rule of thumb of 30%.

So I'm just building a little veg closet, 0.50 x 1 x 0.96m (that's 1.6 x 3.3 x 3.1 ft) in dimension.
So my volume is 0.48m³, times 12 changes per hour = 5.76m³/hr
Adding in the filter's resistance ( x1.3) takes me to 7.5m³/hr or 264cuft/hr or 4.4CFM ?!?
Does that sound right or am I juglling numbers in lalaland? :bigjoint:
Cheers!
Well if you read thru that documentation it does explain it all, you can read it if you want but ill basically summerize it. There is no real legal standard on how many ACH is required for a Hazmat remediation for something considered toxic like aesbestos. The basic minimum standard is 6ach but more isnt a bad thing. Now ill explain how we generally run it in a toxic situation.

When doing a remediation of a large very contaminated structure for something like aesbestos (toxic airborne particulate) there are air testing machines at the chamber entrances that constantly monitor it to ensure that negative air pressure is maintained to a certain level so that there is zero possibility of any particulate escaping other than thru the filtered negative air machine. We are also required to periodically take air samples within the areas of the structure that workers are present. Most of the time my job isnt responding to emergency situations, its doing air sampling on more basic remediations to ensure safety of workers and public around that area. So for us, there is no golden rule of so many ACH that works for any and all situations, the minimum standard tho is 6 per hour and thats in a very low level of contamination.

The more contaminated the area the more PPM (parts per million) will show up in air sampling and we then need to adjust to have more cfm by either adding in more neg air machines or if they are on lower settings to turn them to a higher speed.

So if youre running 12 an hour, thats a good thing and you should be okay. If youre running a space thats very cramped with a very smelly plant, it means if i took an air sample the PPM would be very high and you'd need higher than that bare minimum of 6 ACH and possibly near that 12ach but id suspect not quite that high. Now if you were running a 4x4 with 2 very smelly plants you likely wouldnt even need 6 ACH as there would be less of a PPM concentration in the air. You should be more than okay with 12ach but the ultimate confirmation is going to be your own nose because im pretty sure you dont have the equipment to air sample. If i was running a cramped grow id aim for that 10-12 ach range but be running a multiple speed fan and try lowering it until i found a balance of high enough to elminate smell but as slow as possible to use less power, less noise, more longevity of carbon ect. I would guess youre 12 ach should cover even the most crowded spaces, but there are so many factors that can affect it. Even something like high humidity can lower the efficience of carbon and have that ACH reuired be higher.

Your numbers sound good to me but ultimately it comes down to what air sampling says and adjust accordingly. For a grow op and smell the air sampling device is your nose. As far as the cfm ratings for fan and filter you 25-30 would be pretty bang on for a HEPA situation, with a carbon only situation you can get away with less of a difference because carbon has less air resistance than a HEPA would.

Super condensed response, 12 should be more than enough but you should know if its enough just by if you can smell your plants.
 
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haze010

Well-Known Member
Ps. some of my stuff will be full of spelling errors and sometimes words mixed up and garballed grammatically, i have dislexia so written communication from me sometimes comes out garbelled but i think i make it mostly understandable. If that doesnt clarify your question feel free to ask again and i can try to reword it differently.

Due to my dislexia me and math are bitter enemies, i always get someone else to check any numbers i ever run and in a workplace situation i have a program in a small tablet ive attached to my own air sampler where i just punch in the numbers and it spits out the answer, so please dont ask me to verify your math. You do absolutely have the concept down and im sure using any form of tech u can confirm your runnning the numbers correctly.

For those that do not quite understand what dyslexia is its actually very common and very under-diagnosed. For the curious glance over this document and i can 100% guarentee you willl recognize these exact traits in someone you know or went to school with, some estimate it affects as much as 10% of ppl in some varying degree of severity.

https://www.dyslexia.com/about-dyslexia/signs-of-dyslexia/test-for-dyslexia-37-signs/
 
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Alrighty, I am back with an update. Currently growing 3 plants. Durban Poison, Pineapple Express and Kosher Kush. They are all 12/12 from seed.

Durban Poison - March 3 sprout. Currently in flowering. It is forming up nugs. Little to no smell.

Pineapple - First two leaves died, in veg. Smells CRAZY already. Shit scares me.

Kosher - same as Pineapple, also smells CRAZY.

But!!! Lets come to the topic of Ozone. I can tell you, without Ozone, the whole room smells of them. As soon as I turn on my 200mg/h Ozone, the smell is gone in under 1 minute. My room is small but not so small. I keep the ozone on for 10 to 20 minutes max every hour. Room smells fresh and clean everytime I enter.

When I put my nose up to the growbox, I do smell the CRAZY smell. So it is safe to say that ozone doesn't enter into the box so much. Fine by me. I need to room to smell clean, not the box.

As soon as I open the box, I am bombarded by the smell, which dies in 20 secconds with Ozone.

Seems to me like this will work fine. Fingers crossed. I do have a 600mg machine cleaning my water and for emergencies further down flowering if needed.
I know ozone generators are dangerous for humans, are they also dangerous to cannabis plants?
 

vamoz

Member
I know ozone generators are dangerous for humans, are they also dangerous to cannabis plants?
In high dosage, it is dangerous for both. Now, if you use it in low settings and you know what you are doing, it might actually be beneficial for both. My allergies are much better and I am sleeping in the room where the ozone machine is. I have two of them. I one them is 200mg/h and the other one is 400mg/h. I find the 200 enough for most of the day. I only need to run the 400mg 1 or 2 times. All of my 3 plants are flowering in a tiny ass room so there is a lot of smells in that room. Ozone helps me kill it.
 
Thanks for the info! I think I might try using one for the smell of my girls. I just need to do a bit more research before committing lol
 

haze010

Well-Known Member
Thanks for the info! I think I might try using one for the smell of my girls. I just need to do a bit more research before committing lol
Why anyone would ever go down the road of ozone generating is beyond me. Carbon filtering is the way to go, i wont beat a dead horse but read the link i put in to professonal industrial level air scrubbing. There is no reason ever use something that warns you to vacate the area before using, and then use it in your home when there is 100% safe, less expensive, and much more effective option.

If you arent using carbon filtering you're doing it wrong.

https://learn.allergyandair.com/ozone-generators/

https://learn.allergyandair.com/activated-carbon-filters/
 
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vamoz

Member
Why anyone would ever go down the road of ozone generating is beyond me. Carbon filtering is the way to go, i wont beat a dead horse but read the link i put in to professonal industrial level air scrubbing. There is no reason ever use something that warns you to vacate the area before using, and then use it in your home when there is 100% safe, less expensive, and much more effective option.

If you arent using carbon filtering you're doing it wrong.

https://learn.allergyandair.com/ozone-generators/

https://learn.allergyandair.com/activated-carbon-filters/
I give you a couple of reasons... Stealthgrow with people living with you, less noise, less electric usage, lower cost, lasts longer. Of course carbon is better but when you need to do it stealth... it changes things. About the health issues, those warnings are for stupid retards so they don't hurt themselves. You can find ozone generators in humidifiers made for babies. It is all about how you use it, how much you use it and for how long... If you know these things, it is only beneficial.
 

haze010

Well-Known Member
I give you a couple of reasons... Stealthgrow with people living with you, less noise, less electric usage, lower cost, lasts longer. Of course carbon is better but when you need to do it stealth... it changes things. About the health issues, those warnings are for stupid retards so they don't hurt themselves. You can find ozone generators in humidifiers made for babies. It is all about how you use it, how much you use it and for how long... If you know these things, it is only beneficial.
Most stealth cab growers use carbon. Its no louder than a fan which you should already be running anyway, and can easily be silent with a bit of accoustic foam. The effectiveness of carbon boils down to proven science. If you think carbon filtering is expensive then you're pricing a custom made can filter they market specifically for growing use and markup 5000%. You can buy well over a years supply of carbon for a 4x2 space for under $40 and then make a can filter with crap you already have lying around your house.

Theres no reason to ever use ozone generation. Dont listen to the snakeoil salesmen.
 

vamoz

Member
Most stealth cab growers use carbon. Its no louder than a fan which you should already be running anyway, and can easily be silent with a bit of accoustic foam. The effectiveness of carbon boils down to proven science. If you think carbon filtering is expensive then you're pricing a custom made can filter they market specifically for growing use and markup 5000%. You can buy well over a years supply of carbon for a 4x2 space for under $40 and then make a can filter with crap you already have lying around your house.

Theres no reason to ever use ozone generation. Dont listen to the snakeoil salesmen.
Lol at "snakeoil salesmen".

These are only my points of views you don't have to be so harsh about it. Where I am from I can buy 3 ozone generators for the price of a good carbon scrubber with fan.(let alone the upkeep) I bet the shitty cheap fans will make a lot of noise so now we have to up the price. I live with 3 people, most of them come in and out of my room. Using carbon scrubber will mean that I have to cut a big hole in my dresser. My dresser has gaps in it where air can go in and out, which will make it a bit harder to hold the negative air pressure for the scrubber. It took me ages to deal with the light leak without cutting off air inside the dresser.

Now you talked about fans and how they make noise. People I live with know that I have allergies, so I did justify the noise coming from my ozone generator when it is running with minimal noise. (not audible outside my room anyway but when they are in my room, they know what is making "that" noise.) At the end of the day, I would use it even after my harvest, it did actually help me health wise. I am not using those "whythefuck" 5g/h machines either. Now those will hurt you bad if you don't know what you are doing.

I am merely a noobie grower. This is what I think... You can take it or not. P.S. I ain't sending any links for purchase either. I am not selling anything.
 

haze010

Well-Known Member
Lol at "snakeoil salesmen".

These are only my points of views you don't have to be so harsh about it. Where I am from I can buy 3 ozone generators for the price of a good carbon scrubber with fan.(let alone the upkeep) I bet the shitty cheap fans will make a lot of noise so now we have to up the price. I live with 3 people, most of them come in and out of my room. Using carbon scrubber will mean that I have to cut a big hole in my dresser. My dresser has gaps in it where air can go in and out, which will make it a bit harder to hold the negative air pressure for the scrubber. It took me ages to deal with the light leak without cutting off air inside the dresser.

Now you talked about fans and how they make noise. People I live with know that I have allergies, so I did justify the noise coming from my ozone generator when it is running with minimal noise. (not audible outside my room anyway but when they are in my room, they know what is making "that" noise.) At the end of the day, I would use it even after my harvest, it did actually help me health wise. I am not using those "whythefuck" 5g/h machines either. Now those will hurt you bad if you don't know what you are doing.

I am merely a noobie grower. This is what I think... You can take it or not. P.S. I ain't sending any links for purchase either. I am not selling anything.
The snakeoil salesmen i meant ppl selling can filters for $200 that has $25 worth of bulk carbon and some rolled aluminum and the ppl who convinced you to go ozone. In my mind your the guy the snakeoil salesmen convinced.

Im just trying to give people advice from an air quality professional. I wasnt calling you a snakeoil salesman, i was calling the ppl selling expensive can filters that. You can make the exact same thing they sell for pennies on the dollar. As far as alergies ect, theres a reason hospitals and labs use hepa + carbon. Throughout this thread ive provided plenty of links that teach the science of what i am saying....

Feel free if you want to read them but i back my opinion with 2 decades of professional air quality experience and the science to proove it to ppl who dont want to listen. If ozone works for you, thats awesome. I will never recommend it tho.
 
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If I'm not using a grow tent will I have a problem with negative/positive air pressure in my grow room when using a carbon filter or scrubber? There are small gaps around the door to my room would they effect air pressure?
 

haze010

Well-Known Member
If I'm not using a grow tent will I have a problem with negative/positive air pressure in my grow room when using a carbon filter or scrubber? There are small gaps around the door to my room would they effect air pressure?
Well youre confusing two completely different things when you say air scrubber and negative air. They are two different setups and both can be very effective. A negative air setup is a mostly sealed area, like a tent, where contaminated air is sucked thru filtering and the cleaned air is exhasted outside that tent. This is whats used in toxic hazmat setups. Its called negative air because the air being sucked out is at a pressure higher than the mostly sealed tent will let in, it means the only way air can escape is thru the filter. It doesnt require a tent but the more air leaks you have the stronger your fan is going to have to run. Just a closed closet door is enough of airtight if your fan is good enough.

An air scrubber is just like negative air but it has no exhaust it just recirculates the clean air to the room. Generally an air scrubber will need a stronger fan and more cfm but it means the room itself will have almost zero odor. In a 100% sealed grow space of a contained room using CO2 they would use an air scrubber setup.

Either willl work great if they are setup properly and have sufficient cfm thru the filtration.
 

calliandra

Well-Known Member
Well if you read thru that documentation it does explain it all, you can read it if you want but ill basically summerize it. There is no real legal standard on how many ACH is required for a Hazmat remediation for something considered toxic like aesbestos. The basic minimum standard is 6ach but more isnt a bad thing. Now ill explain how we generally run it in a toxic situation.

When doing a remediation of a large very contaminated structure for something like aesbestos (toxic airborne particulate) there are air testing machines at the chamber entrances that constantly monitor it to ensure that negative air pressure is maintained to a certain level so that there is zero possibility of any particulate escaping other than thru the filtered negative air machine. We are also required to periodically take air samples within the areas of the structure that workers are present. Most of the time my job isnt responding to emergency situations, its doing air sampling on more basic remediations to ensure safety of workers and public around that area. So for us, there is no golden rule of so many ACH that works for any and all situations, the minimum standard tho is 6 per hour and thats in a very low level of contamination.

The more contaminated the area the more PPM (parts per million) will show up in air sampling and we then need to adjust to have more cfm by either adding in more neg air machines or if they are on lower settings to turn them to a higher speed.

So if youre running 12 an hour, thats a good thing and you should be okay. If youre running a space thats very cramped with a very smelly plant, it means if i took an air sample the PPM would be very high and you'd need higher than that bare minimum of 6 ACH and possibly near that 12ach but id suspect not quite that high. Now if you were running a 4x4 with 2 very smelly plants you likely wouldnt even need 6 ACH as there would be less of a PPM concentration in the air. You should be more than okay with 12ach but the ultimate confirmation is going to be your own nose because im pretty sure you dont have the equipment to air sample. If i was running a cramped grow id aim for that 10-12 ach range but be running a multiple speed fan and try lowering it until i found a balance of high enough to elminate smell but as slow as possible to use less power, less noise, more longevity of carbon ect. I would guess youre 12 ach should cover even the most crowded spaces, but there are so many factors that can affect it. Even something like high humidity can lower the efficience of carbon and have that ACH reuired be higher.

Your numbers sound good to me but ultimately it comes down to what air sampling says and adjust accordingly. For a grow op and smell the air sampling device is your nose. As far as the cfm ratings for fan and filter you 25-30 would be pretty bang on for a HEPA situation, with a carbon only situation you can get away with less of a difference because carbon has less air resistance than a HEPA would.

Super condensed response, 12 should be more than enough but you should know if its enough just by if you can smell your plants.
Thank you so much for your detailed response, it gives me a bit more of a feel for "how much"!
And what an interesting profession too! :D
I think I really want to be able to adust the ACH, and yes you guessed right I will be monitoring nasally haha
Good to know my way of calculating it leads to somewhat usable numbers for orientation, but also good to have a bit of leeway, just in case. Now, to source a fan haha
Cheers! :bigjoint:
 

haze010

Well-Known Member
Thank you so much for your detailed response, it gives me a bit more of a feel for "how much"!
And what an interesting profession too! :D
I think I really want to be able to adust the ACH, and yes you guessed right I will be monitoring nasally haha
Good to know my way of calculating it leads to somewhat usable numbers for orientation, but also good to have a bit of leeway, just in case. Now, to source a fan haha
Cheers! :bigjoint:
Yup happy to help, ive recieved so much help on things i didnt know shit about, this is the one thing im confident i can offer great advice on.
 

Javadog

Well-Known Member
Vamoz you deserve to fight the effect of allergies. A former boss had to live
with a pollen shield mask on most of the time. But let me suggest that you
also consider a negative ion generator. They have the same awesome air
cleaning effect (particle clump up and fall) but not the O3 concerns.
 

vamoz

Member
Vamoz you deserve to fight the effect of allergies. A former boss had to live
with a pollen shield mask on most of the time. But let me suggest that you
also consider a negative ion generator. They have the same awesome air
cleaning effect (particle clump up and fall) but not the O3 concerns.
Hey Java, thank you for this... I do also have a device which has negative ion generator as well as hepa filter. It's life... without these I get constant sneezes back to back until I feel dizzy. Also suffy nose that stops me from having a proper day and etc.

I am much better these days so thats good. Its everything, the things we eat, do, location...

But like I said. Its life, people deal with much worse stuff.
 

Javadog

Well-Known Member
I am the lucky one in my family, the brother got the allergies.

(then again, I had to do all the Weed Whipping ;0)

Oxygen-3 == O3 is not necessary for indoor rigs, but I imagine that an ozone
creating filter on an outlet duct is another safe route.
 

gr865

Well-Known Member
Hell I am allergic to cannabis, everytime I open the tent I sneeze and get stuffed up.
My GF laughs when I open the smoke jar and start sniffeling.
 

calliandra

Well-Known Member
So I'm thinking of making a carbon filter, and have this grain hull biochar here.
Not sure whether I could use it though, given it's got a good portion of very fine material in there?
2017-06-02 07.54.42.jpg

What do you guys think?
Should I just see whether a fine pantyhose can contain it?
I've also seen a build that uses extractor hood filters as a cover for the carbon...
Wouldn't want biochar dust floating around in the air haha
Cheers!
 
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