The City of Chicago has specific codes regarding emergency egress sign-age (what products may be used and where these products must be placed). These codes are covered in section 13-160 of the Chicago Municipal Code.
The City of Chicago has the following requirements for exit signs:
- Signs must be rectangular 20 gauge sheet metal box with a glass or plastic face
- Signs must be red lettering on white
- The letters and arrows of exit signs and exit sign/emergency light combos are MANDATED to be red.
- Directional Arrows are beneath the sign lettering and are the same width as the lettering
- All Exits Signs need to be internally illuminated with at least a 10 watt "electric lamp"
The Chicago Municipal Code is available online here: http://www.amlegal.com/codes/client/chicago_il/.