The distance from the butt of one shingle to the butt of the shingle above it, or the amount of a shingle that is seen.

The act of permitting light to fall upon a photosensitive material.

The state of being open to some action or influence that may affect detrimentally, as cold, disease, or wetness.

The general surroundings of a site, with special reference to its openness to winds and sunshine.

1. The total quantity of radiation at a given point, measured in air.

2. The cumulative amount of radiation exposure to which nuclear fuel has been subjected in a nuclear reactor; usually expressed in terms of the thermal energy produced by the reactor per ton of fuel initially present, as megawatt days per ton.

See <<light exposure>>, <<radiant exposure>>