Issue link: https://hi.iaq.net/i/655416
28 Energy Savings Plus Health | INDOOR AIR QUALITY GUIDELINES FOR MULTIFAMILY BUILDING UPGRADES PRIORITY ISSUE 6.0 BELOWGROUND CONTAMINANTS (EXCEPT RADON) ASSESSMENT PROTOCOLS (AP) MINIMUM ACTIONS (MA) EXPANDED ACTIONS (EA) AP 6.1 Evaluate Potential Sources and Odors Perform a walkthrough inspection and visually evaluate potential sources and check for gasoline, sewer gas, or fuel oil odors. Pay particular attention to ground-contact spaces, mechanical rooms, and areas with drain, waste and vent piping. AP 6.2 Evaluate the Sewer Vent System Visually evaluate the integrity of the sewer vent system (e.g., ensure drain traps have water in them, inspect drain lines for breaks or leaks, check for apparent blockages), particularly if there is sewer gas odor in the building (e.g., during the initial assessment or a fan depressurization test). AP 6.3 Take Proper Actions if the Odor Source Cannot be Identified If an odor is detected but its source cannot be identified, and the building is in a known area of contamination, notify local or state authorities and/or pursue additional assess- ments before continuing project work. AP 6.4 Conduct Further Assessment if Contamination is Suspected If soil or groundwater contamination is suspected on or near the building site (e.g., former industrial site), volatile contaminants or breakdown products may pose an IAQ risk through soil gas intrusion. In such cases, EPA recommends further assessment before air sealing. Consult your state or tribal voluntary Brownfields cleanup program or environmental regulatory agency for information on the risks of vapor intrusion in your area. ASTM E2600 describes a tiered approach for screening properties for vapor intrusion and Table X5.1 of the standard provides a list of state vapor-intrusion guidance websites. Note: A records search of the property and surrounding areas may provide information regarding past uses and spill reports. MA 6.1 Repair Unattached Sewer Vent System Components Repair or replace failed or unattached sewer vent system components before proceeding with building upgrade projects. MA 6.2 Address Drain Traps Prone to Drying Out If the assessments reveal sewer gas odors from drain traps that are dry because of infrequent use, develop a maintenance plan to periodically add water to the traps to maintain a seal against sewer gases. Consider installing inline drain trap seals on floor drains prone to drying out. Note: Because of their continuous usage, drain traps in sinks, toilets and drinking fountains seldom are a problem. Usually it is a floor drain in an obscure location, such as a mechanical room or a maintenance closet. Dry drain traps in mechanical rooms are especially problematic because mechanical rooms often contain heating, cooling and ventilation systems that can quickly spread the gases and odors to other parts of the building. Unitary equipment (e.g., heat pumps) can have dry drain traps, which often results in the undesirable odors being limited to one room. MA 6.3 Mitigate Soil Gas Vapor Intrusion If soil gas vapor intrusion is confirmed during the assessments, mitigate in compliance with state or local standards. Table X5.1 of ASTM E2600 provides a list of state vapor intrusion guidance websites. If there are no state or local standards for your area, follow the EPA guidance referenced below for vapor intrusion evaluation and mitigation. Note: The causes or sources of contaminants must be identified and corrected before air sealing or other building upgrade actions are performed to ensure the problem is not exacerbated. EA 6.1 Install Floor Drain Seals to Untrapped Floor Drains If there are untrapped floor drains, install inline floor drain seals to provide protection against sewer gases. EA 6.2 Install Automatic Drain Trap Primers Install automatic drain trap primers, available from several major manufacturers, in drain traps that are susceptible to drying out to ensure that a small amount of water is periodically delivered to the trap. EA 6.3 Take Proper Measures for Brownfields Sites During New Construction or Building Expansion Projects located on Brownfields sites (as classified by a federal, state or local government agency) involving new construction or expansion of a ground- level foundation should include features to prevent migration of soil-gas contaminants into occupied spaces, as described in the ASHRAE Indoor Air Quality Guide, Strategy 3.4. References for Priority Issue 6.0 Belowground Contaminants (Except Radon): ASHRAE: Indoor Air Quality Guide, Strategy 3.4 ASTM: E2600-15 Standard Guide for Vapor Encroachment Screening on Property Involved in Real Estate Transactions EPA: Building Air Quality Action Plan, Step 2: Develop an IAQ Profile of Your Building, Part 2: Conduct a Walkthrough EPA: Engineering Issue. Indoor Vapor Intrusion Mitigation Approaches EPA: IAQ Design Tools for Schools. Preventing the Entry of Pollutants from Outside the Building. Drain Traps EPA: Technical Guide for Assessing and Mitigating the Vapor Intrusion Pathway from Subsurface Vapor Sources to Indoor Air EPA: Vapor Intrusion