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How Long for Mattress VOCs to Offgas?

mattress vocs; mattress; unboxing

In a previous blog post, I established that Casper and Tuft & Needle foam mattress VOCs were very high in the packaging and that they should be opened outdoors.  For good measure, I tested yet another manufacturer’s product… Nest Bedding’s Love Bed.  I got the same results as with the other manufacturers:

What do all these videos prove?  They demonstrate that foam mattresses shipped straight to your home should be opened outdoors and allowed to air out.  But that begs the question, “For how long should they air out?”

To test that question, I did a “backyard” experiment after testing the Nest Bedding mattress.  I pressed my VOC measuring device (ppbRAE 3000 photoionization detector) right up against the mattress.  The video below shows what happened over the next 24 hours:

So as you can see in the video above, it’s important to not only open your mattress outdoors, but let it air out also.  The vast majority of VOC emission occurs in the first hour, and drops considerably after a day.   The mattress will continue to off gas at a much lower rate for an unknown amount of time, which is true of all furniture, finishes and building materials.

For a frame of reference, I let my foam mattresses air out for 2 days before bringing them indoors.  Once inside, I kept the windows open in the bedroom for a week as weather allowed.  If you are chemically sensitive, consider letting your foam mattress air out for even longer (or skip foam altogether).

These backyard experiments have lots of limitations. Nevertheless, they demonstrate that independent tests should be carried out in the mattress industry. I hope this message doesn’t fall on deaf ears. Share this blog post and pass on the message!

Ian Cull

Ian Cull is a nationally recognized expert in the field of indoor air quality. He is the Chief Science Officer of Indoor Science, a company he started in 2004. He speaks around the world on air quality topics and is a training provider of the Indoor Air Quality Association. Mr. Cull is a Licensed Professional Engineer (PE) and Certified Industrial Hygienist (CIH). His degree is in Environmental Engineering from the University of Illinois - Urbana Champaign. Mr. Cull has developed 50 air quality related courses for the IAQA University and is the author of the book, “Fundamentals of Mold Remediation”. In his words… “Besides being passionate about indoor air quality, I enjoy cycling, music, the Chicago Bulls, and having fun with my three kids.”

44 thoughts on “How Long for Mattress VOCs to Offgas?

    Hi I am in Australia and four weeks ago I received an ICare mattress in a box. The chemical smell is so strong that we have been able to smell it from the kitchen. Everyone that comes into the house can smell it. I have only got 1 1/3 lung and I am on oxygen. Could this be bad for my health. The smell is starting to fade a little. What would be your advice.

    I’m not a doctor so I cannot provide you with any medical advice. We advise people to open the mattress outdoors and let it air out for a day, ideally in the sun.

    Hi Ian,
    I just got a Polyutherane foam backrest that smells strongly of chemicals. I left it outside for about 12 hours before I had to bring it in due to rain. It doesn’t really smell of the chemical anymore – does that mean the off-gassing is mostly done? I’m trying to figure out how I can tell when it is safe to use. Thanks!

    The perceivable odor is only a crude method of evaluating the off-gassing. However, without fancy instruments or lab work, it’s the best you have. You can pay close attention to any symptoms you experience when sleeping with it for the first time. If there is no smell and no symptoms, you have a much lower risk.

    So, I did not know any of this, and We put our “Bed in a Box” mattress directly on the bed and slept on it that night. I cannot sleep very well on this mattress and we have had it for about 4 years. Would this mattress be DONE of gassing into my room? or, should I still put it outside for a while? Just wondering why I can’t sleep. I have autoimmune disease, and am thinking that this mattress is NOT helping me!

    After 4 years, it would be off-gassing very little. There would be very little benefit to airing it out now.

    It’s freezing cold in Minnesota and have our new brentwoood cypress foam mattress outside to off gas. Will it off gas in freezing cold temperatures? How do I most effectively off gas in freezing temperatures. Also, this bed is oeko-Tex, greenguard certified and certi-our, does that really mean less VOC concerns? Where if I still detect an odor it’s non toxic?

    When it is cold outside, that greatly diminishes the rate of off-gassing. Maybe, in that case, I would open it up outside and let it air out in the cold for a few hours. After that, maybe I would finish the airing out indoors in a room with the door shut and the window slightly open. Or even better, you could keep it in a bathroom with the exhaust fan running (if it fits). Industry certifications mean less VOC concerns, but I would always recommend opening foam mattresses outside.

    I have a question. I’m in need of a topper as my arthritis gets worse it hurts a lot. I have access to a memory foam topper that is over 10 years old now and only used by one person. Do you think it’s done all of its’ offgassing? I do have MCS fairly bad. Does foam ever stop offgassing? Thanks for any reply. Edy

    It should be done with the vast majority of its off-gassing. Any off-gassing at 10 years is minimal.

    Hi Ian, thank you for this. I spent many hours researching and trying to find an affordable mattress that is made of organic or at least natural materials that won’t off-gas. I chose a Saatva mattress that has yet to arrive. However, I’m kicking myself because I bought an adjustable bed frame from another company because it was less expensive, and I never thought about the possibility it would have polyurethane in the frame. I looked at the tag when it arrived and felt like crying…made in China and it has polyurethane in it. I made my husband put it outside, where it has been for about 24 hours (and will remain for a few days). I went back to read the product description on the website that I bought it from, and it says “upholstered grey linen like fabric” and “meets 16 CFR Part 1633 Federal flammability (open flame) standards.” If you were me, would you return it, or do you think the amount of polyurethane it has in it, in addition to being left outside for a few days would be safe to have in my home. Thank you for any input you have about this.

    Much depends on your level of individual sensitivity. For most people, airing it out for a day outside is sufficient. However, if you react to it even after airing it out, I would suggest returning it.

    The problem with foam is that it not only off-gases VOCs, but often it has flame-retardants which are a whole other problem.


    My husband bought a Nest foam mattress and it’s smells musty to me like it was wet and now smells like mold. We had it in the garage in the original wrapper for 4 days. We were out of town when it was delivered and our neighbor put it in the garage for us. I live in Arizona so there was no rain here so it never got wet or anything like that. I can’t even lay on the bed as of this day even with a mattress pad, fitted and flat sheets and a quilt because the smell is so over powering. Is this normal? I was telling my husband he should send it back for a new one because this is just not right to me. I get that there is supposed to be some off gassing odor but it’s been at least 6 weeks and I can’t even go in the bedroom without getting a headache 10 minutes later. What do you think?

    I would not use a mattress that was giving off a strong odor weeks later and was giving me headaches. I suggest you talk to the manufacturer for a replacement or refund.

    Thank you for this great information! I have a foam mattress and am considering replacing it with something non-toxic. Is it true that 100% latex mattresses—as long as they do not contain adhesives—do not off gas VOCs?


    I don’t believe anything until I test it and unfortunately, I haven’t had the chance to test a 100% latex mattress yet.

    1. How can I document off-gassing on my memory foam mattress. I need to prove to the furniture company that I am having problems with my mattress after 4 months in my home?

    2. Are you aware of particular off-gassing problems on memory foam mattresses sold by Bob’s Furniture?


    1. You’ll need to hire a company to use a handheld instrument like the one I used in the video or you would need to do a laboratory-based test. You would need to do multiple areas/tests as they may claim elevated VOCs were coming from things other than the mattress. So you would need a reading/test right at the mattress, and others away from the mattress.
    2. I’m not familiar with those particular issues.


    Hi Ian, thanks for the article. this is something that I’ve been looking into. I wanted to ask…. Is it true that off gassing will continue on for the life of product or is there no curing that happens and VOCs are no longer released? what about the product going through biodegrading? as it breaks down will it release gasses? Would this apply to paints too?

    The rate of off-gassing decreases over time. You do get to a point where there is very little off-gassing occurring (so low that it would be difficult to measure). On a different note, nothing in this world stays the same and everything degrades. But the natural degradation generally is not a release of gases, but rather particles. This would apply to paints too.

    Am I correct in assuming that just because my mattress has an odor, doesn’t mean that odor is indicative of VOCs?

    My Casper definitely has a smell–not an offensive smell, but certainly a distinct smell–after about 48 hours.

    Many, but not all, odors are a VOC. Not every VOC has the same degree of health risk. Did you air the mattress outside as we recommend?

    I didn’t have that luxury, but I did air it out inside.
    I left it about two days with a fan blowing on it.
    I still noticed a smell, so I unzipped the cover and allowed it to air for another two days with the foam exposed directly to the air.

    I’m about two weeks out now, and it still has a bit of an odor. Not too strong, though.

    Thank you so much for publishing your findings. As a young family buying a new mattress this is priceless information.

    Hello Mr. Cull,

    Thank you for such important information.
    I was wondering if you have any info on offgassing of air bed mattresses or do you even recommend them at all.
    Most are made of PVC, but I also worry about pthalates, etc. How long do these chemicals offgas? Is it safe to sleep on an airbed?
    I was also wondering if you have done any other related research and found what kind of bed is the safest to sleep on.

    Thanks again, Elaine

    Unfortunately, I haven’t tested any air mattresses for VOC off-gassing. The compounds you mentioned (PVC, phthalates) are typically non-volatile (not readily found as a vapor in the air), but can be found in the dust.
    I haven’t tested other beds for VOC off-gassing, but I would assume that innerspring mattresses are much lower than foam. Others have concerns over innerspring mattresses due to electromagnetic fields.
    For someone with chemical sensitivities, I would suggest trial and error until you find one that works.

    Thank you so much for your post. I purchased a linenspa memoryfoam mattress on Amazon which smelled absolutely aweful when we first opened it. I left it outside for about a month. I can no longer smell an odor, but still worry about the gasses that I can not detect. I have not been able to find any studies r/t how long the gasses might be present. Do you know of any brands that have lower levels of VOC’s besided completely organic mattresses which are outrageously expensive?

    I haven’t tested any others, but I am interested in evaluating a completely organic one. IMHO I think a month of off-gassing is more than sufficient.

    This is a fantastic article! I work in the pediatric rehabilitation field as an Occupational Therapist and am occasionally involved in assisting clients ordering custom mold seating for their wheelchairs. Some of these wheelchairs return from the factory with such a toxic order that off gassing outside for days still doesn’t help. I would like to ask you about local testing services.

    Hi Ian,
    I just found this link, I have a Serta Briggs Double Mattress, have left it outdoors for 4 days and 1 night and still smell the off gas. I am disgusted by this revelation and wonder why more people do not know about this. Thank you for your help in verifying this. I don’t know what to do, and hope the Sleep Country where I bought the mattress takes it back.

    “Open your mattress outdoors and let it air outside for two days” is not very useful advice for the trillions of urban earthlings who don’t have so much as a balcony, (and often no more than one room). How about some practical advice?

    I would suggest doing what you can. Open it up outside and let it air out for an hour if that’s all the time you can spare. That would be better than nothing.

    Opening the mattress outside and leaving it there overnight isn’t something most people can do, especially if you live in an apartment. But it was interesting to see how much gas the mattress lets out. I just bought a Tuft and Needle. It had a slight smell and I’ll have to let it air out inside.

    @Jim, I haven’t. The items I have tested are those I personally purchased for my own use.

    Great post – so glad to have found this. I just bought a Casper mattress, and the smell was really potent. I locked it in a room with an open window and a couple of fans running to try to mitigate before we sleep on it. Yours is the one truly substantive piece on this topic.

    If you don’t have an outdoors — what protocol should i do for airing out the mattress indoors?

    Seriously, all that crap is going into the air where we breathe it anyway. why not just get a healthier version to begin with. I never slept as good as I did once I got an organic cotton mattress with wool. Pure bliss.

    Wow. I have been researching the CertiPUR-US certification and its associated group (the PFA), and I am completely disgusted. You can go to the PFA’s website and download the PDF of benefits for membership to the PFA, and they brag about succeeding in ” efforts to resist a move to have the Department of Transportation classify flexible polyurethane foam as a hazardous material” as well as altering air quality standards and promoting the interests of MANUFACTURERS…not customers or their safety. I am just…so disgusted with all of these companies, and the FAKE, total BS “certifications” that are purely for Public Relations purposes and NOT for safety at all. Thanks for your information, I really appreciate it.

    Finally, someone who’s providing quantitate information on mattress safety. Thank you very much Ian!

    There’s a lot of conflicting information about how dangerous foam mattresses are due to VOCs and latex being far better. I read in a few places that Nest Bedding was non-toxic; it would appear that’s not quite true.

    I’ve very curious to know how the mattresses you have ( Casper,Tuft & Needle and Nest Bedding) compare in VOC emissions now that they’ve been in your house for quite some time. I’d also be interested to see if results are different if measured from the top of the mattress instead of the side (my kids often sleep with they nose right against the top).