RMS-LB 2018 with 12/20 Revisions

ASD (revised 12/20) 21 ANSI/AARST RMS-LB 2018 (with 1220 revisions) Radon Mitigation Standards for Schools and Large Buildings b) block any necessary access to any areas requiring maintenance or inspection such as mechanical equipment or a crawl space . Exception: Flexible coupling disconnects or equivalent methods prescribed in Section 6.2.6 are permitted where allowed by code to provide access by temporary removal and airtight replacement of ASD pipe sections. 6.2.10 Protect ducts from the elements (insulation) Duct piping shall be provided with thermal insulation in accordance with the following two requirements: a) Where it is likely on a regular basis (e.g., annually or every few years) that freezing temperatures will result in ice buildup within duct piping that would adversely affect system performance, duct piping shall be provided with thermal insulation that is protected from the elements. Under this condition the insulation R-value shall be not less than 4. Note—For more extreme climates, greater R-values may be appropriate; and b) Where it is likely that condensation on exterior surfaces of duct piping would damage building materials, duct piping shall be provided with thermal insulation. Under this condition, the insulation shall have an external vapor barrier and shall have an R-value of not less than 1.8. 6.2.11 Observe codes 10 Informative advisory —Codes that impact choices for pipe routing include but are not limited to: a) Codes intended to maintain the integrity of a building’s structural members. These codes place limits on the extent and location for sawing, notching and boring holes in a building’s structural support members. In example, codes normally prohibit: 1. notches in solid wood joists, rafters and beams within the middle 1/3 rd of its span and notches greater than 1/6 th of its width, and 2. holes that are closer than 2 inches to the top or bottom of solid wood members; b) Fire codes intended to inhibit the spread of fire and smoke. In example, national codes normally prohibit flammable materials such as plastic pipe from: 1. touching or being too close to heat sources to include flues and chimneys, 2. compromising fire/smoke barriers between floors (e.g., metal barriers in flue chases), and 3. penetrating a fire-rated assembly unless specific procedures are taken, such as installing fire collars to control the spread of fire and smoke (e.g., a garage wall or ceiling if constructed as a fire-rated component and at penetrations into upper floor dwellings ); and c) Codes and local utility company restrictions regarding proximity of piping and electrical components that could: 1. inhibit access for inspection and repairs, and 2. be ignition sources for flammable materials (such as an electrical switch that is located near natural gas meters and liquid propane or gasoline holding tanks). Note—The Companion Guidance provided with ANSI/AARST SGM-SF provides examples of code text. 10 As point of reference, see the International Residential Code (IRC) as published by the International Code Council.