For every controlled area that contains radiation-emitting equipment or sources, signage must be displayed and illuminated at all entrances to protect persons from accidental exposure.
Conventionally, warning signs come in the form of boxes positioned on the walls next to the entrance, containing bulbs that illuminate the signage. This of course causes concern about spacial visibility and ledges for dust particles to collect and infection to spread. To combat these problems, Raybloc pioneered the first Flush Mounted Warning Light.