NASA first developed viscoelastic foam to help astronauts handle the high g-forces of take-off. The Swedish company, Tempur-Pedic, first developed viscoelastic for home use in mattresses, according to Dr. Rick Swartzburg, D.C. The Tempur-Pedic North American launch occurred in 1992 with great success. Now many different companies produce viscoelastic foam bedding.
Foam beds feel much different than spring mattresses. While spring mattresses bounce, foam beds do not. They contour to the body and provide excellent motion isolation. Also, rotating a viscoelastic foam bed isn't as necessary as flipping a spring bed. Typical foam beds last about 20 years.
The Indentation Load Deflection (ILD) rating tells us the firmness of a viscoelastic foam mattress. A 25 percent ILD rating tells us how many pounds it takes to compress a 4 inch mattress 25 percent. The higher the weight, the firmer the mattress, says Dr. Rick Swartzburg, D.C.
Most viscoelastic foam mattresses put off an odor for the first week or so. If made in the United States, this doesn't contain any harmful gasses like formaldehyde, says Swartzburg. New foam simply smells. To get rid of the odor, a bowl of vinegar by the bed helps. Also, keep your windows open day and night for a couple of nights to air it out.
Foam made outside of the United States often flattens much quicker than the foam made in the United States, says Swartzburg. Except for Tempur-Pedic, a Swedish company, buyers should beware of any bed made overseas. The cheaper cost may give you less bed life. Also, some companies claim "USA made" because they assemble the layers in the U.S. Make sure the USA actually produces the foam as well.