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In most regions, including the European Union, Australia, New Zealand, Japan, South Korea and China, exit signs have green lettering. (In this color scheme, red is used to show prohibited activities.) In most European countries pictograms are used in place of the word "exit". European sign directive 92/58/EEC of 24 June 1992 indicates that the signs should be green in colour indicating a safe place of exit. BS EN 1838:1999, BS 5266-7:1999 also governs the emergency lighting applications.
In United States and Canada exit signs can have either red or green lettering, but usually red. This is due to states or cities enacting building codes which specify the sign color. For example, in Maryland and Los Angeles, green is required. New York, New Jersey, and Chicago require that exit signs have red text.
The Canadian National Building codes requires "red letters on a contrasting background or white letters on a red background, at least 114 mm high with 19 mm stroke spelling EXIT or SORTIE when the sign is internally illuminated".[8]
Green fluorescent signs can be seen better in dark conditions than other colors, as the human rod cell is more sensitive to these wavelengths.[9][10]
Newly installed exit signs in Australia are green with white "running man" figure. (AS2293) Canada's 2010 National Building Code, released in November 2010, also calls for a switch from the North American red EXIT/SORTIE signs to the international ISO 'green running man' signs, but in airports in Canada the signs must have French and English (CAN/ULC-S572). It is expected to be adopted into the codes of each province within a few months.[11]