A flush valve is a mechanism used to flush a toilet or urinal. The valve and associated hardware are located within the toilet tank or in the body of the urinal. Most toilets have a lever or push button activator, which is used to operate the flush valve.
Photosensitivity (or sun sensitivity) is inflammation of the skin induced by the combination of sunlight and certain medications or substances.This causes redness (erythema) of the skin and may look similar to sunburn.hotosensitivity (or sun sensitivity) is inflammation of the skin induced by the combination of sunlight and certain medications or substances.
1 This is the most common type of sun-sensitivity drug reaction. 2  It can occur when skin is exposed to the sun after certain medications are injected, taken orally, or applied to the skin.3  The drug absorbs the UV light, then releases it into the skin, causing cell death. Photoallergy. 2  In this case, problems occur when skin is exposed to the sun after certain medicines or compounds are applied to the skin's surface. 3  The ultraviolet (UV) light of the sun causes a structural change in the drug.