Annexure - B

3.If the magnitudes and response times of two or more shots are equal, a steeper slope of rise (shorter elapsed time between onset of signal and signal peak) will indicate which is the leak (or more significant leak if there is more than one) as steepness of slope relates to how quickly the gas was drawn into the leak.

4.If differences are still indiscernible, observing the clear-out times (elapsed time from signal peak to return to background) for each indication can be helpful. A faster clear-out for indications of equal magnitude would imply that the signal with the faster clear-out was nearer the leak.

TEST LOG

The Test Engineer will maintain a Test Log for documenting any pertinent information concerning each test run. The information entered in the Test Log will become a part of the record of the test and a copy will be included as an attachment of the test report.

ACCESSIBILITY

Those areas where access is difficult may need some form of permanent access installed.

Annexure - C

PREREQUISITES

Ensure that the test crew has two (2) sets of walkie talkies for communication in good condition, i.e., one for use and other one as standby. It is very important that the person doing the spraying be in continuous contact with the person at the leak detector.

In leak detection there are two goals: (1) Locating the leak and (2) estimating its relative severity. The latter is accomplished by comparison with the peak response of the test shot.

Annexure - D

CONTROL ROOM / UNIT DATA

8.Equipment on Stand by (under vacuum):

Annexure - E

LIST OF INSTRUMENTS & ACCESSORIES REQUIRED FOR AIR-IN-LEAK TEST

1.Leak Detector Instrument

2.Vacuum pump (about ½ H P )

3.Air Gun

4.Helium gas commercial quality (2 cylinders each of 7 cu. m at N. T. P.)

5.Dual pressure oxygen regulator

6.Copper Tubing for Helium spray (1 meter long & 5- 6 mm dia)

7.Tygon Tubing (15 meter long thick tube suitable to air-gun)

8.Glass Flasks (medium size for moisture collection)

9.Silica Gel (500 gm.)

10.Glass Fittings for Flask

11.SS Vessel (2-3 litre capacity)

12.Sealing Compound

Annexure - F