Hi Zuleika0401,
Welcome to the
Mattress Forum!

... and
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I am sorry about all the issues you are having with the fiberglass particles released through washing the cover of your second-hand mattress. It looks like the fiberglass is coming from your Fire Retardant barrier which was broken down when you machine washed your cover The cover seems to be defective since you shouldn't be seeing glass particles migrating out of the fire barrier. Something like this can indeed can be very disruptive and major emotional stress, not to mention ... the financial stress. I hope you can do some less costly damage control to remove the fiberglass particles that spread throughout your home. At this stage it may be a little extreme replace the appliances in your home, I'd certainly try to use any means to thoroughly clean up the appliances and surroundings, replace the filter in your drier, use a vacuum filter with a HEPA filter and perhaps add a mattress bed bug cover with a waterproof membrane that would keep "insulate" you from the fiberglass particles that may still be in your mattress after the cleaning it.
The “fiberglass” content in the label shows 58% of the inner FR mattresses cover. Both outer and inner covers are made in China. It is great that you contacted “the company”, which I assume is Future Foam, and it is good they offered to replace the mattress and offered some cash. To their credit, they are willing to meet you in the middle as it is very unusual to replace or refund products for second-hand buyers. I have to say I am surprised they offered this.
As an aside, this is a typical example of some unintended consequences ... the USA is passing Fire Retardent laws to “keep people safer” but some of the chemicals companies use to “pass” these regulations are not so good. Figure it out!
Unfortunately, we don't have many posts on the site about cleaning fiberglass throughout the home, but there are some solutions in this
thread here
that you may find helpful. Of course, this is not fiberglass wool or industrial fiberglass but you may also want to read this article from
NYCHealth here
To clean fiberglass dust and debris from surfaces, use wet mops and cloths, or a vacuum cleaner equipped with a HEPA filter. Do not dry sweep or perform other activities that may stir up dust.
Did you see any skin irritation? ... this is the most commonly described problem from fiberglass allergies. Have you had issues with fiberglass allergy in the past? Did Future Foam say if they are no longer using fiberglass in a new mattress replacement they offered to send?
I look forward to any updates or solutions that worked for you to clean the fiberglass dust .. also let us know what you decided to do about your current mattress. I appreciate you sharing this on our forum and raising consumers awareness on checking the law tags.
Phoenix