To contribute to the comfort and well-being of all building occupants by establishing minimum standards for indoor air quality (IAQ).
Mechanically Ventilated Spaces
For mechanically ventilated spaces, meet the requirements of ASHRAE Standard 62.1–2016, Sections 4, 5, 6.2, 6.5, and 7, or a local equivalent, whichever is more stringent.
Provide outdoor air monitors for all mechanical ventilation systems with outdoor air intake flow greater than 1000 cfm (472 L/s). The monitoring device must be capable of measuring the minimum outdoor air intake flow and be capable of measuring the design minimum outdoor air intake flow with an accuracy of +/–10%. An alarm must indicate when the outdoor airflow value varies by 15% or more from the setpoint.
Alternatively, for constant-volume systems that do not employ demand control ventilation, provide an indicator capable of confirming the intake damper is open to the position needed to maintain the design minimum outdoor airflow as determined during the system startup and balancing.
Naturally Ventilated Spaces
For naturally ventilated spaces , meet one of the following ventilation requirements.
Option 1. ASHRAE prescriptive natural ventilation compliance path Meet the requirements of ASHRAE 62.1-2016 with addendum l, Sections 4, 6.4.1, 6.4.3, 6.4.4, and 6.5.
Option 2. ASHRAE Engineered natural ventilation system compliance path Meet the requirements of ASHRAE 62.1-2016 with addendum l, Sections 4, 6.4.2, 6.4.3, 6.4.4 and 6.5.
Option 3. Historic building using ASHRAE prescriptive natural ventilation path This option is available to projects located in a building registered as a local or national historic building.
Meet the requirements of ASHRAE 62.1-2016 with addendum l, Sections 4, 220.127.116.11-18.104.22.168, 6.4.3, 6.4.4, and 6.5.
Comply with at least one of the following monitoring strategies.
- Provide a direct exhaust airflow measurement device capable of measuring the exhaust airflow. This device must measure the exhaust airflow with an accuracy of +/–10% of the design minimum exhaust airflow rate. An alarm must indicate when airflow values vary by 15% or more from the exhaust airflow setpoint. This strategy is not allowed for projects using Natural Ventilation Option 3. Historic building.
- Provide automatic indication devices on all natural ventilation openings intended to meet the minimum opening requirements. An alarm must indicate when any one of the openings is closed during occupied hours.
- Monitor carbon dioxide (CO2) concentrations within each thermal zone. CO2 monitors must be between 3 and 6 feet (900 and 1 800 millimeters) above the floor and within the thermal zone. CO2 monitors must have an audible or visual indicator or alert the building automation system if the sensed CO2 concentration exceeds the setpoint by more than 10%. Calculate appropriate CO2 setpoints using the methods in ASHRAE 62.1–2016, Appendix D.
The indoor air quality procedure defined in ASHRAE Standard 62.1–2016, Section 6.3 may not be used to comply with this prerequisite.
Mechanical ventilation systems must be capable of meeting projected ventilation levels and monitoring based on the requirements of anticipated future tenants.
In addition to the requirements above, if the project building contains residential units, each dwelling unit must meet all of the following requirements:
- Design and install a dwelling-unit mechanical ventilation system that complies with ASHRAE 62.2-2016, Sections 4, 6.7, and 6.8, or a local equivalent, whichever is more stringent. Supply and balanced mechanical ventilation systems must be designed and constructed to provide ventilation air directly from the outdoors. Mechanical ventilation systems are not required when the project meets the exception to Section 4.1.1 of ASHRAE 62.2-2016.
- Design and install local mechanical exhaust systems in each kitchen and bathroom (including half-baths) that comply with ASHRAE 62.2-2016, Sections 5 and 7 or local equivalent, whichever is more stringent. Exhaust air to the outdoors. Do not route exhaust ducts to terminate in attics or interstitial spaces. Recirculating range hoods or recirculating over-the-range microwaves do not satisfy the kitchen exhaust requirements. For exhaust hood systems capable of exhausting in excess of 400 cubic feet per minute (188 liters per second), provide makeup air at a rate approximately equal to the exhaust air rate. Makeup air systems must have a means of closure and be automatically controlled to start and operate simultaneously with the exhaust system. Use ENERGY STAR–labeled bathroom exhaust fans in all bathrooms (including half-baths) or performance equivalent for projects outside the U.S. A heat recovery ventilator (HRV) or energy recovery ventilator (ERV) may be used to exhaust single or multiple bathrooms if it has an efficacy level meeting the ENERGY STAR Technical Specifications for Residential Heat-Recovery Ventilators and Energy-Recovery Ventilators (H/ERVs) Version 2.0 as certified by the Home Ventilating Institute (HVI).
- Unvented combustion appliances (ovens and ranges excluded) are not allowed.
- Carbon monoxide (CO) monitor must be installed on each floor of each dwelling unit, hard-wired with a battery backup. CO monitors are required in all types of units, regardless of the type of equipment installed in the unit.
- Any indoor fireplaces and woodstoves must have solid glass enclosures or doors that seal when closed.
- Any indoor fireplaces and woodstoves that are not closed combustion or power-vented must pass a backdraft potential test to ensure that depressurization of the combustion appliance zone is less than 5 Pa.
- Space- and water-heating equipment that involves combustion must be designed and installed with closed combustion (i.e., sealed supply air and exhaust ducting) or with power-vented exhaust, or located in a detached utility building or open-air facility.
Meet the requirements of ASHRAE Standard 170-2017, Sections 6-10, and meet the requirements above for monitoring for mechanical ventilation systems.
Europe ACP: Naturally Ventilated Spaces
Projects in Europe may use the following approach:
- Design the spaces for natural ventilation. Consider typical site-specific local weather conditions, site location and terrain, outdoor environmental impacts (noise, car or industrial emissions, etc.), and the comfort and well-being of the occupants.
- Perform a design study for the building owner and building users comparing the advantages and disadvantages of the natural ventilation concept with a mechanical ventilation concept.
- Comply with the following minimum ventilation areas per person:
Table 1. Minimum ventilation area
The provided areas are the sum of supply an exhaust areas for an applicable room depth up to 10m. For the calculations use the number of people in the ventilation zone during use. To calculate ventilation area, if the window is covered with louvers, insect screens, or otherwise obstructed, the openable area must be based on the free unobstructed area through the opening.
Additionally, comply with the monitoring requirements outlined in the credit.
Submittal Documentation for Europe ACP:
Provide a narrative demonstrating the natural ventilation concept can contribute to the comfort and well-being of the occupants. Include the following information:
0,35 m² / person
1,05 m² / 10 m² room area
0,2 m² / person
0,6 m² / 10 m² room area
- Design studies which compare the natural ventilation concept with a mechanical ventilation concept along with a description of the advantages and disadvantages for the building owner and building user.
- Description of the principal natural ventilation concept (single-sided or cross-ventilation). If the design proposes a mix of the two, provide plans and/or sections with highlighted areas for each of the natural ventilation modes.
- Description of the proposed façade openings (type of windows, louvers, etc.) and their opening mechanisms
Latin America ACP: Engineered Natural Ventilation Systems
Projects in Latin America may follow the Verification Protocol for Engineered Natural Ventilation Systems in Equatorial Climates and receive a design review and approval from the Colombian Professional Association of Air-conditioning, Ventilation and Refrigeration (ACAIRE).