Heath Consultants Optical Methane Detector (OM) - Manual (Page 44)

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of the designated streets, particularly where a single main
exists, with long services running to the opposite side in
a wall-to-wall pavement area. Experience shows that
many curb line service leak indications are detected when
a mobile unit surveys both sides of the street.
E. Tests of Available Openings
Available openings, as described by the American Soci-
ety of Mechanical Engineers (ASME), are openings large
enough to allow a man to enter (i.e., sewer and telephone
manholes, catch basins, vaults, etc.)
F. Report Requirements
Several report forms may be required. The report forms
for a particular survey will be specified on the survey
orders or by the supervisor.
See the Heath Field Manual for specific instructions for
each form specified. All areas surveyed shall be desig-
nated by one (1) of the following:
1. Daily Color-coding Map
2. Daily Service Line Listing
3. Daily Street Listing
IV. Classification of Indicated Leakage Areas
(See also Leak Classification section of Heath Field
Manual)
Each location where combustible vapors are detected
and centered will be classified, in the judgement of the
consultant, as a 1(C), 2(B) or 3(A) leak location. (Leak
grades based on A.S.M.E. standards.)
1. Grade 1(C) - A leak that represents an existing or
probable hazard to persons or property, and requires
immediate repair or continuous action until the
conditions are no longer hazardous.
A
PPENDIX
A