Disinfection of Pipelines - Disinfection of Pipelines and Storage Facilities Field Guide - page 32

or 5.5 m), the connection pipe is disinfected and bacteriological
samples tested as previously described. The pipe should be con-
nected to the distribution system after obtaining satisfactory test
results. The ends of the predisinfected connection pipe should be
covered during the testing and before the connection is complete.
Note: The bacteriological test is the final step in a sanitary installation
process that includes inspection, use of proper materials and protection of
pipes during installation, cleaning and flushing, and employing adequate
disinfection procedures.
Documentation
Accurate records should be kept to document the installation
conditions and test results (including water quality testing). The
records should identify persons that conducted tests and that
released the pipeline for service. The as-built plans should be
completed identifying the types and locations of valve boxes,
hydrants, and other appurtenances. The valve opening direction
and any flow test results for hydrants should be recorded.
Pipeline Chlorination Method Specifics
Specific procedures for implementing each of the three pipe-
line chlorination methods are described in the following section.
The procedures include tables and calculators for determining
the necessary information to efficiently and accurately chlorinate
pipelines.
Tablet Method
Calcium hypochlorite tablets (or granules) are placed in the
water main as it is being installed. The main is then filled with
potable water. This procedure cannot be used on solvent-welded
plastic or on screwed-joint steel pipe. Fire or explosion may result
from the reaction of calcium hypochlorite and joint compounds.
This method also cannot be used if the main must be flushed
before it is disinfected, because this process would remove the
calcium hypochlorite from the main.