number and size of cables and as approved by the Engineer shall be provided:
- Straight run without bend : Max. spacing 30 metres
- Run with one 90o bend : Max. spacing 20 metres
- Run with two 90o bend : Max. spacing 15 metres
?? Adaptable Boxes
Adaptable boxes shall also be made of 16 SWG sheet steel and painted and finished to the same quality as the Lighting distribution boards. The adaptable box shall preferably be fixed adjacent to the DB and have suitable dimensions to match the installation with DB. However, in any case, the depth of adaptable box shall be according to number and size of cables and conduits shall not be less than the following:

- Conduits upto 25 mm dia : Min. depth = 50 mm
- Conduits upto 38 mm dia : Min. depth = 65 mm
- Conduits upto 50 mm dia : Min. depth = 90 mm
- Conduits more than 50 mm dia : Min. depth = 2 x dia

32.4.3 Galvanized Iron (G.I.) Pipes and Accessories
The G.I. pipes shall be made of mild steel, galvanized inside and outside by hot-dip galvanizing process. The pipes shall be free from stain, burrs or any other defect. The accessories for G.I. Pipes such as sockets, bends, etc. shall be also galvanized inside and outside and of same quality and specifications as the pipes.

These pipes shall be installed for crossing of cables above nallas and culverts and at entry into building. The pipes and accessories shall be provided with one thick coat of bituminous paint on the outer surface prior to installation. All pipes shall be secured in position by means of galvanized clamps, supports, etc.

G.I. pipes as manufactured Karachi Pipe Mills Ltd., or approved equivalent shall be provided.

32.4.4 PVC Pipes and Accessories
The PVC pipe shall be rigid. All pipes shall be minimum Class ‘D’ (working pressure – 12 bar), unless otherwise stated on Drawings or Bill of Quantities. The buried PVC pipe should be able to withstand the external load acting upon it by continuous