CC-1000_2018

Soil Gas Control Systems ANSI/AARST CC-1000 2018 in New Construction of Buildings 10 5.7.4 Perforated pipe—Inlet obstructions 5.7.4.1 Perforated pipe: Perforated pipe shall be oriented or augmented to provide unobstructed inlet openings to soil gas while also providing water drainage from the bottom portion of the piping. The calculation for openings to soil gas in perforated pipe as specified in Section 5.7.1 shall not include openings that are effectively closed by adjoining surfaces of soil gas retarders, concrete or packed soil. Drainage of these air ducts shall include no less than 1/2-inch (1.3 cm) diameter opening or equivalent with multiple openings located near the bottom of piping for every 10 feet of duct pipe length. 5.7.4.2 Pipe perforations: Pipe perforations shall not be large enough to allow gravel to enter and obstruct the duct. Where perforated pipe is placed in a layer of sand or small stone, materials or methods shall be employed to not allow sand or small stone to enter perforations and thereby obstruct the duct. 5.7.5 Geotextile mats and woven fabric products 5.7.5.1 Duct opening: The void space within the mat that represents air duct piping shall comply with Section 5.6 including retention of cross-sectional dimensions for main trunk, secondary trunk or branch ducting and transitions. Soil gas inlet surfaces or openings shall comply with Section 5.7 . 5.7.5.2 Woven products: Woven geotextile products such as those intended to retain integrity for the size of the void space that represents an air duct shall not be used as a standalone inlet , duct or gas permeable layer . 5.8 Transition connection to exhaust vent piping 5.8.1 General Rigid, non-perforated piping in accordance with specifications stipulated in Section 8.7 (Piping materials) shall be configured to transition from soil gas inlets or inlet trunk networks within soil gas collection plenum(s) to above the concrete slab or soil gas retarder membrane that represents the top of the plenum . 5.8.2 Transition air volume and pressure loss The portion of non-perforated piping or materials configured to connect between soil gas inlets or inlet trunk networks to above the concrete slab or soil gas retarder membrane shall be: a) sized no less than the exhaust vent pipe (e.g., main trunk, secondary trunk or branch pipe) above the concrete slab or soil gas retarder membrane and retain flow capacity in accordance with Section 5.6 ; and b) included in calculations for maximum pipe length as stipulated in Section 8.6 , “Exhaust vent pipe equivalent length and pressure loss.” 5.8.3 Future connection to exhaust piping Exhaust vent piping that transitions from the gas permeable layer to above a slab or membrane shall extend no less than 2 feet (60 cm) above the slab or membrane and shall be temporarily capped or closed during construction to prevent debris from entering. The portion of pipe that will reside above the slab or membrane shall be marked or labeled with the words “ radon vent,” “ soil gas vent” or similar wording. 5.8.4 Sump inlets not permitted Inlet openings in the form of duct or exhaust piping are not permitted on sump lids. 5.8.5 Collection wells or pits Pits that are designed to transition or join multiple trunks or branches shall be permitted to minimize pressure loss where multiple ducts are joined. 5.9 Test ports Test ports required in Section 7 shall b e installed prior to closure of membranes over soil and casting of slabs when drilling through a cured slab will present hazards or could compromise other building systems such as: a) post-tension slabs with steel tendons; b) radiant heat systems with heat conveyance components located within or under a slab); and c) spray-applied vapor barriers and geomembranes intended to form a homogenous closure for chemical containment. 5.10 Prior to concrete slabs or soil gas retarders 5.10.1 Secure the ducting All subslab or submembrane fittings shall be mechanically fastened, taped or secured in a manner to help avoid dislocation that can occur during installation of aggregate, soil gas retarders and concrete. 5.10.2 Inspect the open plenum An inspection shall be conducted prior to placement of concrete or soil gas retarders over a gas permeable layer to verify that all inlets and ducting are secured and that gas permeable layer materials and closed surroundings are compliant with this standard. The inspection shall include items listed in Exhibit A-1 . A Figure 5.8.5a Example Well/Pit: Open to Soil Gas Figure 5.8.5b Example Well/Pit: Enclosed