OHS Code Explanation Guide

Published Date: July 01, 2009
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Part 40 Utility Workers – Electrical

Explanation of Rules Referenced from the ECUC, Second Edition

Rule 4-190 Work methods

This rule presents the techniques that a qualified utility employee must follow when using barehand techniques. Specifically, the worker must

(a) use rated insulating devices when approaching energized parts,
(b) maintain the limit of approach distances specified in Table 4-2, column 4 and Table 4-4, columns 4 and 5,
(c) measure the actual limit of approach distances rather than simply estimate them,
(d) use shielding and bonding methods and equipment – these will be described in the employer’s operating procedures as required by rule 4-188(e), and
(e) not reach across insulators that have not been jumpered – this is intended to keep the qualified utility employee at the same potential as his or her immediate work area.

Table 4-2 Limit of Approach Distances in Millimetres for Qualified Utility Employees (See Rules 4-136 & 4-148)

Voltage Levels

Qualified Utility
Employees

Nominal voltage to
ground
 
kV

Nominal voltage
phase
to phase
kV

Maximum operating
voltage phase to
phase
kV

Limit of approach
to exposed
energized
parts mm

Column 1

Column 2

Column 3

Column 4(1)

0.6 (DC only)

 

 

500

2.4

4.16

4.58

500

8.0

13.8

15.18

550

14.4

25

27.5

650

19.9

34.5

37.95

750

 

69, 72

79.2

1050

 

138, 144

158.4

1350

 

230, 260

285

1850

 

500

550

3150

Note:
(1) Limit of approach distances in Column 4 have been calculated using IEEE minimum tool distances plus 450 mm safety factor, rounded to the nearest 50 mm.

Table 4-4 Limit of Approach Distances in Millimetres for Qualified Utility Employees Performing Live Line Work Using Barehand Techniques (See Rule 4-148)

Voltage Levels

Qualified utility employees

Nominal voltage
to ground
 

 
kV

Nominal voltage
phase to phase
 
 
 
kV

Maximum
operating
voltage phase
to phase

kV

Limit of approach for work
performed from a rated insulated
device or from an energized phase
conductor

Energized body
parts to
exposed
structure
surfaces or
grounded parts

Mm

Energized body
parts to exposed
adjacent phases
 
 
 
 
mm

Column 1

Column 2

Column 3

Column 4(1)

Column 5(2)

2.4

4.16

4.58

(3)

(3)

8

13.8

15.18

(3)

(3)

14.4

25

27.5

(3)

(3)

19.9

34.5

37.95

(3)

(3)

 

69, 72

79.2

610