Blue Signal indicates?

• A. A blue flag indicating workers.
• B. A block signal that indicates occupancy.
• C. A bulletin order.
• D. A clearly distinguishable blue flag, blue light or blue tag by day, or a blue light or blue tag by night. When displayed, it signifies that workers are on, under or between equipment.

Answer: (D)

In NORAC, a blue signal is a protection for workers on or around equipment. It is shown by a clearly distinguishable blue flag, blue light, or blue tag by day, or a blue light or blue tag by night. When you see it displayed, it means workers are on, under, or between equipment, so movements in that area must be protected and proceed only under the appropriate safeguards.

The other ideas don’t fit because a blue signal isn’t just a flag indicating workers in general, and it isn’t a block occupancy indication or a bulletin order. The blue signal specifically covers how it’s displayed and what it protects—workers on or around equipment.