PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

The chlorinators shall be arranged in a separate moisture proof chlorine room. The
chlorine room shall be accommodated in connection with chlorine drum storage on
the ground of chemical house. The Contractor shall provide an air tight glazed
partition or windows in the chlorinator room to enable the staff to inspect the rates
without entering the room. Adequate externally switched vapour and chemical
proof lighting shall be provided and detailed by the contractor on the drawing.
Apart from the chlorinators no other equipment shall be accommodated in the
chlorine room. Door ways to the room shall be shown as outward opening and
preferably to the building exterior. The contractor shall include suitable pressure
reducing valves to limit the pressure delivered to 2 bars.
21.9 The standards required for the pipes and fitting shall be:
Pipe work for chlorine gas shall be mild steel seamless to B.S. 3602 C.D.'S. or
H.F.S. or electrical resistance welded pipe to BS 3602.
Pipe couplings shall be with British standard H Flanges (front and back welded)
using ring joints tagged made to 1/16 thickness compressed/asbestos fiber CAF BS
2815 grade B.
Valves shall be of the globe type with forged steel bodies monel metal spindles and
valve heads with malleable cast iron valve seats. Gland packing shall be of Teflon.
Pressure gauges shall be of the silver diaphragm type.
The Contractor shall draw his water supplies from the back wash tank and shall not
provide any facility for feeding the chlorinators from any other source.
Dosing lines shall be provided for post chlorination point for the proposed systems.
21.10 Clear water channel from the filter house.
The Contractor shall provide following safety equipment in the works as a
minimum:
Two Nos. canister type respirators with full face coverage of a make suitable for
chlorine gaseous atmosphere.
Four spare canisters for the respirators.
DTS : Detailed Tender Specification. Page 247