MIL-HDBK-1025/10
Table 11B
Qualified Worker Minimum Working Distances
1
2
3
4
5
6
Nominal System
Flash Protection
Limited Approach
Prohibited
1
Minimum Working Distance
Voltage Range.
Boundary
Boundary
Approach
2
and Clear Hot Stick Distance
Boundary
From
Includes
Phase to Phase
Exposed
Exposed Fixed
Includes Standard Inadvertent
Reduced
Voltage
Movable
Circuit Part
Movement Adder
Inadvertent
Conductor
Movement
Adder
Phase To
Phase To
3
4
Phase
Ground
50 V to 300 V
3ft 0in
10ft
0in
3ft 6in
Avoid Contact
301 V to 750 V
3ft 0in
10ft
0in
3ft 6in
1ft 0in
1ft 0in
0ft
1in
751 V to 2 kV
4ft 0in
10ft
0in
4ft 0in
2ft 3in
2ft 2in
0ft
3in
2.001 kV to 15 kV
16ft 0in
10ft
0in
5ft 0in
2ft 3in
2ft 2in
0ft
7in
15.001 kV to 36 kV
19ft 0in
10ft
0in
6ft 0in
2ft 10in
2ft 7in
0ft
10in
36.001 kV to 48.3 kV
21ft 0in
10ft
0in
8ft 0in
2ft 10in
2ft 10in
1ft
5in
1- Distance between energized parts and grounded objects without insulation, isolation,
or guards.
2- Between worker's hand and working end of stick.
3- Work on three-phase delta systems, and on more than one phase of three-phase wye
systems.
4- Work on single-phase systems, and work on one phase only of three-phase wye
systems.
Table 12
Unqualified Worker Minimum Approach Distances
Voltage to ground
Distance
50 kV or below
3 m (10 ft)
5.1.2 Work Methods in Relation to Worker's Safety. All work will be done
de-energized unless energized line work has been specifically authorized.
5.1.2.1 De-energized Electrical Line Work. Follow the lockout/tagout/tryout
procedures. Remember electric lines are considered energized even though de-energized
and isolated if they have not been provided with proper protective grounding.
5.1.2.2 Energized Electrical Line Work. Work on energized lines and
equipment only when authorized by the Public Works Officer or other designated
authority (per local organization) based on the need to support a critical mission, to
prevent injury to persons, or to protect property. Insulating means should be provided to
isolate workers from a source of potential difference. When authorized, perform
energized line work. Barehand liveline work is prohibited.
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