Abrasion -

A product not adequately protected from scratches or punctures may ultimately reduce protection of internal components, damage performance, or inhibit functionality or reliability by inadvertent exposure to external elements.

Examples of Abrasion caused product failures:

• Scratches in painted metal cause corrosion and subsequent exposure of internal components to fluids and particulate matter.
• Printed circuit board traces, covered by a protective layer, are positioned below a large hard disk drive housing; the housing touches the protective layer; months of subtle, yet continuous vibrations of the drive housing wear through the layer and short to the traces.
• Eyeglasses and cameras without a 'scratch resistance' coating on the lenses become useless after months in a windy, desert environment. Not only do blowing dust particles degrade the lenses, but also so does cleaning the lenses, which are coated with very fine grit.
• A sealed battery was being charged at a very rapid pace and was generating normal internal pressure and heat from the charging process. The battery was near a topside vent in the product and was punctured when a sharp object was dropped through the vent. The battery burst and leaked.