Hazard Marking Requirements

DOE-HDBK-1092-98

Other markings for power requirements are:

1. Voltage.

2. Maximum rated current in amperes.

3. Wattage.

4. Frequency (computer only).

5. Other ratings as specified in the NEC.

(See ANSI/ISA-S82.01-1988 Section 5.3.4 and NEC Section 110-21)

9.8.2 HAZARD MARKING REQUIREMENTS

All enclosures containing exposed energized circuits over 600 volts nominal should be marked

"Danger High Voltage Keep Out" with a label that is permanent. These areas shall be accessible to

authorized personnel only. The label shall be placed in a noticeable location on the access panel to

the enclosure. Mark all other hazards that are associated with the equipment.

9.8.3 OTHER REQUIREMENTS

All equipment markings shall be of sufficient durability to withstand the environment involved and

should be large enough to read.

To obtain the correct chassis load requirements for marking and labeling, monitor individual chassis

while under load. Many chassis have components that are not energized except under certain

conditions.

A normal current draw may be a few amperes, but when the chassis is sourcing current to a load, the

current draw may be much higher. Individual loads, internal and external, may be tabulated and

added to determine the chassis current labeling requirements.

For rack cabinets with power distribution units, the outside of the rack cabinet should be labeled with

the input parameters of the power distribution system installed within it.

For rack cabinets without power distribution units the outside of the rack cabinet should be labeled

with the total current on the combined systems installed within it.

9.9 WORKING CLEARANCES

Clear working space and headroom shall meet the NEC requirements (see Figs. 9-4 and 9-5). The

clear working space and passageways to this space should not be used for storage. At least one 24

inch wide (minimum) passageway should be provided for travel to and from the clear working space.

While maintenance, repair or calibration are being performed, personnel should identify clear

working spaces via suitable means such as "Danger" or "Caution" barrier tape, or barricades to keep

other personnel from entering the clear working spaces. (See Section 2.9.)

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