3.6 INSTALLATION CONTRACTOR QC TESTING
A. The Installation Contractor shall non-destructively test the full length of all
seams to ensure watertight, homogeneous seams. Test methods shall consist of
vacuum box testing, air-pressure testing of double-fusion seams, or other
methods approved by the manufacturer and the CQA Consultant. The test shall
be performed as work progresses, rather than at the completion of all field
seaming.
B. Vacuum box testing shall be performed on extrusion welds using a vacuum box
with a rigid housing, transparent viewing window, a soft rubber gasket on the
bottom edge, and a valve assembly with a vacuum gauge. The vacuum box must
be approved by the CQA Consultant prior to use. The CQA Consultant has the
right to reject any vacuum box that he feels may not provide accurate results.
C. Vacuum box testing shall be performed by applying a soap-and-water solution
to the seam and placing the box over the seam so a leak-tight seal is obtained,
applying a vacuum of 5 psi to the box. The seam shall be examined through the
viewing window for at least 10 seconds by the CQA Consultant for the presence
of soap bubbles. If soap bubbles are detected in the viewing window, the
location will be marked and repaired in accordance with these Specifications.
Vacuum testing shall be performed in accordance with ASTM D5641.
D. Air pressure testing shall be performed on double-fusion seams having an air
channel between the seams. Both ends of the seam shall be heat-sealed and a
hollow needle with a pressure gauge and valve attached shall be inserted into
the air channel. A pump shall be attached to the needle and an air pressure of
25 psi shall be applied to the air channel. The valve shall be closed and the
pressure shall be observed for a minimum of 5 minutes. If the pressure drops
more than 2 psi or doesn’t stabilize, then the defective area shall be located,
marked, and repaired in accordance with these Specifications. After completing
the air pressure test, the needle shall be removed and the hole shall be sealed
and tested with the vacuum box. The CQA Consultant shall witness the entire
test, including the release of pressure or vacuum, to monitor for a defective
pressure or vacuum gauge. Air pressure testing shall be performed in
accordance with ASTM D5820.
E. Destructive testing of seam samples is not required.
3.7. FINALINSPECTION
A. A final inspection shall be performed by the Installation Contractor, the CQA
Consultant, ENGINEER, and OWNER prior to the Installer’s crew demobilizing
from the site. All identified problem areas shall be repaired by the Installation
Contractor and accepted by the CQA Consultant prior to the installation crew
demobilizing from the site.
File No. 3066.21 Geomembrane 02550 - 9 of 10 January 2021
