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.
photosensitivity. [-senâ²sitivâ²itÄ]. 1 sensitivity of a cell to light. 2 any abnormal response to exposure to light, specifically, a skin reaction requiring the presence of a sensitizing agent and exposure to sunlight or its equivalent.Photosensitivity includes photoallergic and phototoxic reactions and is common in systemic lupus erythematosus.he skin is a carefully designed interface between our bodies and the outside world. It is infection-proof when intact, nearly waterproof, and filled with protective mechanisms. Sunlight threatens the health of the skin. Normal skin is highly variable in its ability to resist sun damage.