CC-1000_2018

Soil Gas Control Systems ANSI/AARST CC-1000 2018 in New Construction of Buildings 13 Section 6.3.2 . Informative note — Alternative products include spray-applied vapor barriers and geomembranes intended to form a homogenous closure for chemical containment. 6.4.2 Over crawl space earthen floors The soil gas retarder membrane shall meet ASTM E1745 Class A, B or C and be installed in accordance with Sections 6.3 , 6.4.3 and 6.4.4 . For crawl spaces or portions of a crawl space that are expected to be regularly accessed for maintenance, storage or other purposes, thicker materials or protection of the membrane can be appropriate, and the soil gas retarder shall be fastened to the walls in a durable manner. 6.4.3 Seams The seams between adjacent membrane sheets shall be overlapped not less than 12 inches (30 cm) and shall be sealed by one of the following methods: a) A tape recommended by the membrane manufacturer; or b) Caulk compliant to ASTM C920 class 25 o r greater; or c) An equivalent method. 6.4.4 Repairs Tears or punctures in the membrane shall be sealed by one or more of the following methods: a) A tape recommended by the membrane manufacturer; or b) An additional sheet of the membrane material that covers and overlaps the tear or puncture not less than nominally 12 inches (30 cm) on all sides and that is sealed with a caulk complying with ASTM C920 class 25 or greater; or c) An equivalent method. 6.5 Inspect for closure prior to indoor finishings Prior to completion of indoor finishings, an inspection shall be conducted to verify compliance with this standard and ensure a continuous sealed barrier has been constructed between soil gas and airspaces within the building. The inspection shall include the items listed in Exhibit A-2 . A record of the inspection(s) shall be retained in accordance with Section 12 . Notice : This provision is strongly recommended but not mandatory unless: a) it is required for exercising design options for larger soil gas collection plenums in accordance with Sections 4.3.2 and 4.3.3 ; o r b) it is specifically referenced in contract or local ordinance. See Annex A-1 . SECTION 7: PRESSURE FIELD EXTENSION EVALUATION 7.1 General After slabs have been cast or soil gas retarders in crawl spaces have been installed, an evaluation of newly constructed soil gas collection plenums shall be conducted to verify that no changes are needed for the design of exhaust vent pipe assemblies that will soon be constructed. The evaluation shall include connecting a fan to the primary trunk of the exhaust vent pipe and measuring the resulting vacuum within the gas permeable layer(s) at strategic locations. 7.2 Test port locations Strategic locations of test ports shall include all of the following locations: a) Test port locations remotely distant from the exhaust vent pipe transition to below the slab or soil gas retarder that are sufficient in number to: i) evaluate effectiveness of soil gas transport across the major expanse of the slab or membrane; and ii) evaluate consistency of soil gas transport across soil gas collection plenums that are joined to a shared exhaust vent pipe. b) Not less than one test port for each outer quadrant area of the building while also achieving one test port for each soil gas vent system and each soil gas collection plenum joined to a single soil gas vent system; and c) For larger expanses allowed in Section 4.3.2 and 4.3.3 , not less than one test port for each outer quadrant area of soil gas collection plenums that are 8,000 sq. ft. (744 m 2 ) or larger while also achieving one test port for each additional 8,000 sq. ft. (744 m 2 ) area; Exception: Where there are no openings or utility penetrations through the slab or soil gas retarder, test ports are not required for plenum areas that are less than 64 square feet (6 m 2 ), or collectively represent less than 10% of any 4,500 square foot (418 m 2 ) area. 7.2.1 Preinstalled test port locations Where test ports are installed prior to casting slabs as required in Section 5.9 , additional test port locations shall include: a) ground contact rooms designed to be under significant negative pressure (e.g., industrial use kitchens, clean-rooms or similar); and b) additional locations, as required, for measuring concentrations of hazardous soil gas or vapors.