Areas with flammable, combustible, or ignitable materials are illuminated by hazardous location lighting fixtures. They're also known as hazloc lights since they contain arcs and sparks so that the fixtures don't catch fire or explode. They have NEC and OSHA class and division ratings for usage in locations where specified risks exist in normal or abnormal situations. Group ratings are also assigned to Class I and II fixtures, indicating whether they should be used in areas containing specified types of gas, vapor, or dust. Round fixtures offer a small footprint and a classic jelly jar appearance. Linear fixtures have a long body that allows light to spread out across a large region. From high ceilings, square fixtures provide high-output light. Signal and warning lights demarcate restricted areas or notify individuals of potential dangers nearby. During power outages, emergency and exit lights illuminate to guide people out of buildings. Existing hazloc fixtures are converted to LED, which lowers running costs and improves light quality.