Emergency Shutdown

DOE-HDBK-1092-98

All cord-connected equipment should have one of the following as a disconnecting device:

1. A switch or circuit breaker,

2. Plug that can be disconnected without the use of a tool, or

3. A separable plug, without a locking device, to mate with a socket-outlet in the building.

Where equipment is connected to the source of supply by flexible cords having either an attachment

or appliance plug, the attachment or appliance plug receptacle may serve as the disconnect (ANSI/

ISA - S82.01 - 1988 - Section 13.10.1 and NEC Section 422-22).

Where a switch is not part of a motor, motor circuit or controller, the disconnecting means should

be within 50 feet and in sight of the operator and marked as the disconnection device for the

equipment.

Where a disconnecting means is not part of the equipment, the disconnecting means should be near

the equipment, within easy reach of the operator during normal operation of the equipment, and

marked as the disconnection device for the equipment.

If a disconnecting device is part of the equipment, locate it as close as practical to the input power

source.

9.7.2 EMERGENCY SHUTDOWN

The emergency shutdown switch should be within arm's reach of the operator, be easily identifiable,

deenergize all power to all equipment associated with the system, be separate from the routine on/

off switch, and be located to protect the employee from moving parts. However, the emergency

shutdown switch should not disconnect auxiliary circuits necessary for safety (such as cooling).

9.7.3 SPECIAL CONSIDERATIONS

The disconnecting means should interrupt the source voltage for thyristor controlled equipment. Do

not rely on disconnecting the control voltage.

9.8 MARKING AND LABELING REQUIREMENTS

9.8.1 GENERAL MARKING REQUIREMENTS

For all chassis and rack cabinets (electrical, computer, power distribution, etc.), the manufacturer's

name, trademark, or other descriptive marking of the organization responsible for the product should

be identified.

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