Legislation over EXIT signs got moving in 1911, when a fire at a Manhattan garment manufacturer resulted in 146 deaths. As journalist Julia Turner recounts in an article for Slate an insurance industry group called the National Fire Protection Association began to push for laws to "[get] people out of buildings intact." The NFPA set about diligently testing different EXIT sign configurations for effectiveness in emergencies, and the familiar, red sign is what found its way through the scientific process.
Today, the NFPA revises its Life Safety Code every three years. As an insurance industry group, it doesn’t have any regulatory power itself, but its long and rigorous experience in fire safety means its recommendations carry extra weight with states and localities, which routinely adopt its rules.
So there’s a reason why the ubiquitous EXIT sign looks the way it does. According to the US Occupational Safety and Health Administration’s Standard 1910.37(b) sections 1-7, exits in public places have to be clearly marked with “plainly legible letters not less than six inches high, with the principal strokes of the letters in the word “Exit” not less than three-fourths of an inch wide."
OSHA thinks exit signs are so important that not only do they have to be posted, they always have to be visible. OSHA dictates that exit signs "must be illuminated to a surface value of at least five foot-candles by a reliable light source." Some EXIT signs are photoluminescent and glow in the dark, but these still have to have a luminescence surface value of at least .06 footlamberts. (The footlambert is named after Johan Lambert, a Swiss astronomer, and one footlambert is the equivalent of a candle's brightness in a one-foot space.)
Many EXIT signs remain plugged in during the day, with backup batteries that charge continuously in case of electrical fault. Others give off a pale green glow using a combination of the harmless radioactive element tritium and phosphor gasses.
Entrance signs serve a different but equally important function. From direction signs that point the way to the emergency room to signs that direct traffic (think DELIVERIES), an entrance sign has done its job when we know exactly where to go without giving it a second thought. Filtering foot traffic into discrete groups makes it easier for visitors to get around, but also helps provides goals – a key wayfinding guideline. Employee entrance signs, student entrance signs and do not enter signs all provide passersby with information they need to feel secure in their environment.
For people with disabilities, entrance signs are essential – wheelchair-bound visitors need to know where to go to avoid major inconvenience. The Americans with Disabilities Act requires public and commercial buildings that aren’t totally handicapped accessible to mark accessible entrances with signage so that visitors with mobility limitations can find their way to their destination.
These signs must include the international accessibility symbol – the universally recognized wheelchair – and must also follow sizing and color guidelines set out by the ADA. (For example, there must be a 70% contrast between lettering or pictograms and their backgrounds to aid the visually impaired.) Reputable sign companies are aware of the ADA’s guidelines and make their signs with them in mind.
Knowing which way is in can save a life.
The high contrast between the accessibility pictogram and the background isn’t just a design choice – it’s meant to make the sign more readily visible to users.
Regulations are subject to change, so do some research to be sure that your facilities are in compliance with local and federal regulations and standards.