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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To promote occupants’ comfort, well-being, and productivity by improving indoor air quality.
Requirements
Comply with 3 strategies for 1 point or 6 strategies for 2 points
Strategy 1. Entryway Systems
Install permanent entryway systems at least 10 feet (3 meters) long in the primary direction of travel to capture dirt and particulates entering the building at regularly used exterior entrances. Acceptable entryway systems include permanently installed grates, grilles, slotted systems that allow for cleaning underneath, rollout mats, and any other materials manufactured as entryway systems with equivalent or better performance. Maintain all on a weekly basis.Strategy 2. Interior Cross-Contamination Prevention
Sufficiently exhaust each space where hazardous gases or chemicals may be present or used (e.g., garages, housekeeping and laundry areas, copying and printing rooms), using the exhaust rates determined in EQ Prerequisite Minimum Indoor Air Quality Performance or a minimum of 0.50 cfm per square foot (2.54 l/s per square meter), to create negative pressure with respect to adjacent spaces when the doors to the room are closed. For each of these spaces, provide self-closing doors and deck-to-deck partitions or a hard-lid ceiling.Strategy 3. Filtration of Outdoor Air
Each ventilation system that supplies outdoor air to occupied spaces must have particle filters or air-cleaning devices that meet one of the following filtration media requirements:- minimum efficiency reporting value (MERV) of 13 or higher, in accordance with ASHRAE Standard 52.2–2017; or
- Equivalent filtration media class of ePM1 50% or higher, as defined by ISO 16890-2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance.
Strategy 4. Filtration of Recirculated Air
Each ventilation system that supplies recirculated air to occupied spaces must have particle filters or air-cleaning devices that meet one of the following filtration media requirements:- minimum efficiency reporting value (MERV) of 13 or higher, in accordance with ASHRAE Standard 52.2–2017; or
- Equivalent filtration media class of ePM1 50% or higher, as defined by ISO 16890-2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance.
Strategy 5. Increased Ventilation 15%
Increase breathing zone outdoor air ventilation rates to 95% of all occupied spaces by at least 15% above the minimum rates as determined in EQ Prerequisite Minimum Indoor Air Quality Performance.Strategy 6. Increased Ventilation 30%
Increase breathing zone outdoor air ventilation rates to 95% of all occupied spaces by at least 30% above the minimum rates as determined in EQ Prerequisite Minimum Indoor Air Quality Performance.Strategy 7. Operable Windows
75% of the regularly occupied spaces have operable windows that provide access to outdoor air. The windows must meet the opening size and location requirements of ASHRAE 62.1-2016 with addendum l, section 6.4.1.2.Strategy 8. Engineered Natural Ventilation
Achieve Option 2. ASHRAE Engineered natural ventilation system compliance path under EQ prerequisite. Minimum Indoor Air Quality Performance.Strategy 9. Carbon Dioxide Monitoring
Monitor CO2 concentrations within all densely occupied spaces. CO2 monitors must be between 3 and 6 feet (900 and 1 800 millimeters) above the floor. 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 methods in ASHRAE 62.1–2016, Appendix D.Strategy 10. Additional Source Control and Monitoring
For spaces where air contaminants are likely, evaluate potential sources of additional air contaminants besides CO2. Develop and implement a materials-handling plan to reduce the likelihood of contaminant release. Install monitoring systems with sensors designed to detect the specific contaminants. An alarm must indicate any unusual or unsafe conditions.IAQ-HIGH">East Asia ACP: Filtration Media
Projects in East Asia may use filtration media classified as high efficiency (高中效过滤器) or higher as defined by Chinese standard GB/T 14295-2008 (空气过滤器). See all forum discussions about this credit »What does it cost?
Cost estimates for this credit
On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.
Our tab contains overall cost guidance, notes on what “soft costs” to expect, and a strategy-by-strategy breakdown of what to consider and what it might cost, in percentage premiums, actual costs, or both.
This information is also available in a full PDF download in The Cost of LEED v4 report.
Learn more about The Cost of LEED v4 »Frequently asked questions
See all forum discussions about this credit »Addenda
"The credit has been restructured to a list of 10 strategies. New strategies are included for (1) filtration of recirculated air, (2) increased ventilation at 15% above prerequisite levels, and (3) operable windows.
Referenced standards for Strategy 4. Filtration of recirculated air and Strategy 9. Carbon dioxide monitoring have been updated to recent versions as follows: :
ASHRAE 52.2-2010 ASHRAE 52.2-2017
EN 779-2002 ISO 16890-2016 ASHRAE 62.1-2010 ASHRAE 62.1-2016
The strategies for natural ventilation and mixed mode ventilation have been updated to align with EQ prerequisite Minimum indoor air quality performance to encouraging natural ventilation design beyond prescriptive values as defined in ASHRAE 62.1-2016 addendum L as naturally ventilated engineered systems.
The strategy for Exterior Contamination Prevention has been removed from this credit but may be pursued as an innovation credit.
"
Under Step-by-Step Guidance, replace with following text:
"Step 1. Select strategies
Determine which strategies the project will pursue.
Step 2. If pursuing Strategy 1 Entryway Systems
Refer to LEED v4 reference guide, Option 1. Enhanced IAQ Strategies, Entryway systems
Step 3. If pursuing Strategy 2. Interior Cross-Contamination Prevention
Refer to LEED v4 reference guide, Option 1. Interior Cross-Contamination Prevention and use ASHRAE 62.1-2016, Table 5.5.1 that lists minimum separation distances for air intakes.
Step 4. If Pursuing Strategy 3. Filtration of Outdoor Air
Follow LEED v4 guidance for specifying outdoor air filtration media meeting credit requirements for minimum efficiency reporting value (MERV) ratings per ASHRAE standard or equivalent filtration media class of ePM1 50% or higher per ISO 16890- 2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance instead of EN 779-2002- Class F7 filters or higher.
Step 5. If Pursuing Strategy 4. Filtration of Recirculated Air
Identify all HVAC equipment that supplies recirculated air to occupied spaces and specify filtration media that meet the credit requirements for minimum efficiency reporting value (MERV) ratings or equivalent filtration media class.
Step 6. If Pursuing Strategy 5. Increased Ventilation 15 Percent
Follow the EQ Prerequisite Minimum Indoor Air Quality Performance prerequisite’s steps for mechanical ventilation systems to determine the amount of outdoor air that must be supplied by each ventilation system. To meet the credit requirements, the system must deliver 15% more outdoor air to 95 percent of the occupied spaces at all times the space is occupied. For multiple-zone recirculating systems, this will likely increase the required outdoor air intake for the system by more than 15%.
Step 7. If Pursuing Strategy 6. Increased Ventilation 30 Percent
Follow the EQ Prerequisite Minimum Indoor Air Quality Performance prerequisite’s steps for mechanical ventilation systems to determine the amount of outdoor air that must be supplied by each ventilation system. To meet the credit requirements, the system must deliver 30% more outdoor air to 95 percent of the occupied spaces at all times the space is occupied. For multiple-zone recirculating systems, this will likely increase the required outdoor air intake for the system by more than 30%.
Step 8. If Pursuing Strategy 7. Operable Windows
Identify all regularly occupied spaces and collect the following information for each space:
Location of openings (on one side, two opposite sides, or two adjacent sides),
Size of the opening (openable area).
Review section 6.4.1.2 in ASHRAE 62.1-2015 addendum l for window size and location requirements and compare the results with the design. Revise if necessary, to ensure that all regularly occupied spaces meet the requirements.
Step 9. If pursuing Strategy 8. Engineered Natural Ventilation
This strategy is met if the project complies with natural ventilation Option 2 under the EQ Prerequisite Minimum Indoor Air Quality Performance.
Step 10. If Pursuing Carbon Dioxide Monitoring
Refer to LEED v4 reference guide, Option 2. Additional Enhanced IAQ Strategies, Carbon Dioxide CO2) monitoring section . UseASHRAE 62.1-2016, Appendix C for determining CO2 concentration set-points.
Densely occupied spaces are defined as: an area with design occupant density of 25 people or more per 1,000 square feet (93 square meters).
Step 11. If Pursuing Additional Source Control and Monitoring
Refer to LEED v4 reference guide, Option 2. Additional Enhanced IAQ Strategies, Additional Source Control and Monitoring"
Under Further Explanation add new section for Required Documentation and Exemplary Performance:
Required Documentation
Strategy 4. Mechanical schedules highlighting MERV or filtration media class for all units that supply return air
Strategy 6. Increased ventilation: confirmation (calculations are documented under EQ Prerequisite Minimum Indoor Air Quality Performance)
Strategy 7. Diagrams or description of location of operable windows and opening size calculations
Strategy 8. Natural ventilation confirmation (calculations are documented under EQ Prerequisite Minimum Indoor Air Quality Performance)
Exemplary Performance
Comply with 8 strategies
Add the following section at the top of the requirements language: "Comply with 3 strategies for 1 point or 6 strategies for 2 points
Replace text for Option 1 A with "Strategy 1"
Replace text for Option 1 B with "Strategy 2"
Replace text for Option 1 "C. Filtration" with "Strategy 3. Filtration of Outdoor Air"
Add new strategy " Strategy 4. Filtration of Recirculated Air
Each ventilation system that supplies recirculated air to occupied spaces must have particle filters or air-cleaning devices that meet one of the following filtration media requirements:
• minimum efficiency reporting value (MERV) of 13 or higher, in accordance with ASHRAE Standard 52.2–2017; or
• Equivalent filtration media class of ePM1 50% or higher, as defined by ISO 16890-2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance.
Replace all air filtration media after completion of construction and before occupancy.
Data Centers only
The above filtration media requirements are required only for ventilation systems serving regularly occupied spaces. "
Delete Option 1 strategy D and Option 1 strategy E.
Delete Option 2, strategy A
Add new strategy " Strategy 5. Increased Ventilation 15 Percent
Increase breathing zone outdoor air ventilation rates to 95% of all occupied spaces by at least 15% above the minimum rates as determined in EQ Prerequisite Minimum Indoor Air Quality Performance."
Replace text for Option 2 "B. Increased Ventilation" with "Strategy 6, Increased Ventilation 30 Percent" and add "to 95%" so the text reads: Increase breathing zone outdoor air ventilation rates to 95% of all occupied spaces by at least 30% above the minimum rates as determined in EQ Prerequisite Minimum Indoor Air Quality Performance.
Add two new strategies:
"Strategy 7. Operable Windows
75% of the regularly occupied spaces have operable windows that provide access to outdoor air. The windows must meet the opening size and location requirements of ASHRAE 62.1-2016 with addendum l, section 6.4.1.2.
Strategy 8. Engineered Natural Ventilation
Achieve Option 2. ASHRAE Engineered natural ventilation system compliance path under EQ prerequisite. Minimum Indoor Air Quality Performance."
Replace text for Option 2 "C" with "Strategy 9"
Replace text for Option 2 "D" with "Strategy 10"
Delete Option 2 "E"
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Intent
To promote occupants’ comfort, well-being, and productivity by improving indoor air quality.
Requirements
Comply with 3 strategies for 1 point or 6 strategies for 2 points
Strategy 1. Entryway Systems
Install permanent entryway systems at least 10 feet (3 meters) long in the primary direction of travel to capture dirt and particulates entering the building at regularly used exterior entrances. Acceptable entryway systems include permanently installed grates, grilles, slotted systems that allow for cleaning underneath, rollout mats, and any other materials manufactured as entryway systems with equivalent or better performance. Maintain all on a weekly basis.Strategy 2. Interior Cross-Contamination Prevention
Sufficiently exhaust each space where hazardous gases or chemicals may be present or used (e.g., garages, housekeeping and laundry areas, copying and printing rooms), using the exhaust rates determined in EQ Prerequisite Minimum Indoor Air Quality Performance or a minimum of 0.50 cfm per square foot (2.54 l/s per square meter), to create negative pressure with respect to adjacent spaces when the doors to the room are closed. For each of these spaces, provide self-closing doors and deck-to-deck partitions or a hard-lid ceiling.Strategy 3. Filtration of Outdoor Air
Each ventilation system that supplies outdoor air to occupied spaces must have particle filters or air-cleaning devices that meet one of the following filtration media requirements:- minimum efficiency reporting value (MERV) of 13 or higher, in accordance with ASHRAE Standard 52.2–2017; or
- Equivalent filtration media class of ePM1 50% or higher, as defined by ISO 16890-2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance.
Strategy 4. Filtration of Recirculated Air
Each ventilation system that supplies recirculated air to occupied spaces must have particle filters or air-cleaning devices that meet one of the following filtration media requirements:- minimum efficiency reporting value (MERV) of 13 or higher, in accordance with ASHRAE Standard 52.2–2017; or
- Equivalent filtration media class of ePM1 50% or higher, as defined by ISO 16890-2016, Particulate Air Filters for General Ventilation, Determination of the Filtration Performance.