SGM-SF_2017with 12/20 Revisions

Non-ASD Methods 48 ANSI/AARST SGM-SF 2017 (with 1220 revisions) Soil Gas Mitigation Standards for Existing Homes 12.6.2 Passive venting Vents to outside air that are not associated with economizer setback systems shall be non-closeable when installed to increase the natural ventilation of a crawlspace, soil or interior spaces for mitigation purposes. Note—See Section 12.13.3 12.7 Controls for Variable Activation Note—Controls often serve comfort and energy conservation needs by variably cycling the system(s) activation or capacity based upon occupancy patterns and seasonal effects on building systems. 12.7.1 System(s) activation Controls for mechanical equipment shall be configured and verified to activate systems and achieve mitigation goals whenever each portion of the building is occupied . 12.7.2 Labeling required (controls) Control settings and fan monitors shall be labeled and annotated in accordance with Section 8.4.3 c . 12.8 HVAC Repairs or Modifications 12.8.1 Incidental repairs When an incidental failure or condition of a component is suspected of causing radon entry and it can be repaired in a permanent fashion, diagnostic radon tests after completing incidental repairs are an allowed consideration. Should retests indicate mitigation has resulted from an incidental repair: A “Long-Term OM&M Plan” in accordance with Section 13.7.2 is required. Note—The inspection regimen stipulated in Table 13.7 should include observance of items or similar components that appear prone to routine failure and any related systems that are volatile to alteration over time. 12.8.2 Modifications to HVAC systems and controls The intended non- ASD methodology for mitigation shall be identified within this Section 12 (Non- ASD methods) and any resulting actions shall be in compliance with applicable provision(s) of this Section 12 . Regardless if the choice of mitigation method was influenced by desires to address other indoor air quality concerns, an OM&M Plan in accordance with Section 13.7.2 is required when augmenting HVAC systems or controls to include all applicable provisions for each method applied. Informative advisories a) Modifications should comply with appropriate ventilation standards. 10 b) It is also strongly recommended to ensure that the design capabilities of the system are more than is minimally required so that any degradation to the system’s functionality over time can be accommodated as needed. 12.9 Building Materials Note—Where it has been determined that building materials are a primary source of elevated radon concentrations, see Section 12.5 ( Indoor Air Dilution ) as a consideration, if applicable. Other considerations currently beyond the scope of this document include encapsulation, isolation or removal of building materials. 12.10 Water 12.10.1 Radon from water Note—Where it can be determined that radon from a water supply is a primary source of elevated radon concentrations in air, aeration and charcoal filtration are common methods employed to achieve radon reductions. Such methods are currently beyond the scope of this document. 12.11 Source Removal Informative advisories —Methods for removal of hazardous source material are currently beyond the scope of this document, to include: a) excavation for removal of contaminated earth; b) biological or chemical methods that seek to neutralize toxicity of contaminated earth; and 10 For further information, see ANSI/ASHRAE Standard 62.1 “Ventilation for Acceptable Indoor Air Quality” for buildings that are more than three stories tall or ANSI/ASHRAE Standard 62.2 “Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings”