IS 6711:1972 is the Indian Standard (BIS) for maintenance of wood poles for overhead power and telecommunication lines. This standard provides guidelines for the maintenance of wood poles used in overhead power and telecommunication lines. It covers the causes of deterioration, procedures for systematic inspection, and methods for remedial and preventive treatments to ensure structural integrity and extend service life.
Code of practice for maintenance of wood poles for overhead power and telecommunication lines
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Ground-line Inspection Excavation Depth | About 450 mm below ground level. | 18 to 24 inches (approx. 457 to 610 mm) below ground level. | RUS Bulletin 1724E-156 |
| Inspection Boring Auger Diameter | Not exceeding 20 mm. | Typically 3/8 to 1/2 inch (9.5 to 12.7 mm) to minimize damage. | AWPA M19-21 |
| Bore Hole Plugging | Plug with creosoted wooden dowels. | Plug with tight-fitting, preservative-treated plastic or wooden plugs/dowels. | AWPA M19-21 |
| Remedial Ground-line Preservative | Coal tar creosote or a 5% solution of pentachlorophenol. | Copper naphthenate, DCOI, or sodium fluoride/borate based pastes and rods. | AWPA M19-21 |
| Rejection Criteria (Rule of Thumb) | Strength calculation based on remaining sound wood moment of resistance. | Pole may require remedial action or replacement if sound wood shell thickness is less than 2 inches (50 mm). | RUS Bulletin 1724E-156 |
| Initial Major Inspection Cycle | Not explicitly defined; 'annual patrol' from start. | Typically 10-15 years after installation for the first detailed inspection. | ENA TS 43-10 |