Spaces About Electrical Equipment – Working Spaces

Philippine Electrical Code

One of the most taken for granted provision of the Philippine Electrical Code is Section 1.10.2.1 Spaces About Electrical Equipment. It may have been that Electrical Design Engineers and Electrical Inspectors are not aware of the provision, do not understand the provision or just taking the provision for granted. Whatever the reasons will be, it is a clear violation of the Philippine Electrical Code.

Table 1.10.2.1(a)(1) of the Philippine Electrical Code provides the acceptable working space clearances depending on the electrical installation.

Table 1.10.2.1(a)(1) Working Spaces
Nominal Voltage to Ground Minimum Clear Distance (mm)
Condition 1 Condition 2 Condition 3
0–150 900 900 900
151–600 900 1000 1200

Note: Where the conditions are as follows:
Condition 1 — Exposed live parts on one side of the working space and no live or grounded parts on the other side of the working space, or exposed live parts on both sides of the working space that are effectively guarded by insulating materials.
Condition 2 — Exposed live parts on one side of the working space and grounded parts on the other side of the working space. Concrete, brick, or tile walls shall be
considered as grounded.
Condition 3 — Exposed live parts on both sides of the working space.

Sketches below illustrates the installation conditions stated in Table 1.10.2.1(a)(1):

Working Space Condition 1
Working Space Condition 2
Working Space Condition 2
Working Space Condition 3
Working Space Condition 3

References:

  1. Philippine Electrical Code 2009
  2. NFPA Handbook 2011