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A mattress protector, mattress topper, mattress pad, or underpad is an item of removable bedding that sits on top of or encases a mattress to provide protection to the mattress. Some mattress protectors also provide protection to the individual sleeping on the mattress from allergens and irritants such as dust mites, bed bugs, mould, and dead skin (like dandruff).
Protecting the mattress
The simplest form of a mattress protector is a lightly quilted fitted sheet. It provides minimal protection against liquids and little or no protection from dust mite allergens. As well as conventional natural fabrics new forms of synthetic protector or topper have appeared over the years including memory foam and spacer fabrics. These are more expensive than conventional protectors but add the advantages of pressure relief and in the case of the later, the ability to be washed.
Waterproof mattress protectors keep the mattress clean by securing it from absorbing body excretions (such as sweat) or other liquids resulting from spills. These can take the form of flat rubberized flannel pads (commonly used under a bedsheet for infants) or special breathable fitted covers. The plastic pads are hot to sleep on and change the feel of the mattress. A urethane laminate on cotton that has good wicking properties is an alternative to a rubberized flannel pad. A protector with a thin laminate that is not pulled too tightly across the bed will not change the feel of the bed. Also, the laminate is still breathable which means that it won't trap body heat.
Because most mattress warranties are voided if the mattress inherits a stain, most sleepers use mattress pads to prevent from voiding a warranty on their mattress.
Protecting the health of the sleeper
For protection against bed bugs, the mattress and box spring must both be fully enclosed with no possible openings. Zippered cases are commonly used for this purpose. This prevents new bed bugs from getting into the mattress and box spring, and traps any bed bugs that are already inside. Mattress protectors must be left on for at least a full year to make sure that the trapped bed bugs and their eggs die. If the cover is taken off early, the bed bug infestation may relapse.
Waterproof mattress protectors also reduce allergy symptoms by reducing the ability of mould to grow in a mattress. Mattress protectors which can be easily disinfected are commonly used in children's nurseries and health care facilities. A 2002 Norwegian study has found that foam mattresses are 4 to 8 times more likely to host dust mite faeces than spring mattresses.
For more information about mattress protectors, please click on the following link: http://en.wikipedia.org/wiki/Mattress_protector