The “notice to employees” provides relevant safety information for radiation workers and must be posted in a sufficient number of areas near radiation-use areas
X-ray caution signs are required to be posted on any entry door leading to a room containing a permanent radiation-producing machine. Only authorized personnel are permitted to enter areas containing these caution signs.
Caution radioactive materials signs must be posted on any entry door where radioactive materials are used or stored. Only authorized personnel are permitted to enter areas containing these caution signs.
Only standard radiation symbols are permitted to be displayed, using the color magenta, purple or black on yellow background (NRC 10 CFR part 20.1901)