Note that the sign at the right is illuminated... this is not a requirement if there is enough ambient lighting along the exit route in the dental office. However, the size of the lettering is strictly regulated by OSHA. Our guidance to the dental office is to research and implement all applicable standards to ensure the optimum compliance with OSHA.
The link for the signage size standard is:
http://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=19456
For additional information on this topic or any compliance questions please call Dynamic Dental Safety at (888) 669-8846 ext. 701