Is communication equipment distinguished both visually and audibly?
Similar communication equipment should be marked to avoid confusion concerning "which is which". High priority telephones should be distinguished audibly and visually from other telephones. This should be based on a communication specification - which prioritizes communication equipment.
Comments/Recommendations
RSOK S-001, point 9.1, p. 18, NUREG0700, point 10.2.2-7, p. 399.
DC: Intercom, telephone and radio communication equipment should be easily distinguishable.