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

The Contractor's attention is invited to current India Design Codes of Practices and
the Manual of Water Supply and Treatment, 1999 or its latest edition prepared by
the expert committee and published by the Ministry of the works and Housing, New
Delhi, India.
The Commissioning and testing of the plant and trial run of plant under actual
working conditions for continuous 6 months is included in completion period. If
there is any lapse in trial run due to any reason, trial run periods shall be extended to
compensate the lapse to make up. The trial run period shall include atleast
2 continuous months during the monsoon season. In case the monsoon season
conditions are not met with the turbidity in the water for the required maximum
shall be stimulated by adding bentonite clay or to other such compound. The
completion test shall be taken over for the design flow. All consumables except
untreated water during Trial Run period of 6 months shall be arranged and supplied
by the contractor at his own cost. The maintenance defect liability period of
12 months defined elsewhere on the Tender documents shall commence form the
date of issuance of final Acceptance Certificate after successful completion of
commissioning, test and trial run period.
Two Nos. automatic gas leakage detector shall be provided. One each in
chlorinating rooms and in chlorine store.
The Contractor shall provide forced ventilation equipment in the chlorine store and
chlorination room which shall be manually controlled by external switches outside
the rooms at each doorways. The ventilation systems to be provided shall have the
following capacity of air changes per hour upon operation of any one switch for the
store and chlorine rooms and shall extract air at ground level outside the building.
For continuous operation : 3-4 air changes
For Emergency operation : 20 air changes
The contractor shall provide all the purpose made ducts and outlets required. The
ventilation blowers shall be inward blowing at high level for bringing fresh air
exhaust fan with at low level. The machines shall be suitable for use in a damp
chlorinous atmosphere.
Each of the gas metering chlorinators of requirements and types set out in the tender
document shall have the following facilities:
a. Manual adjustment of dose rate
b. Substantially linear scale
c. Internal gas inlet pressure reducing valve
d. Safety vent to be piped to external atmosphere,
e. Pressure and vacuum relief valve.
DTS : Detailed Tender Specification. Page 246