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LEED v4
Healthcare
Indoor Environmental Quality
Minimum indoor air quality performance

LEED CREDIT

Healthcare-v4 EQp1: Minimum indoor air quality performance Required

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Requirements

Meet the following requirements for both ventilation and monitoring.

Ventilation
Mechanically Ventilated Spaces
For mechanically ventilated spaces (and for mixed-mode systems when the mechanical ventilation is activated), determine the minimum outdoor air intake flow for mechanical ventilations systems using the ventilation rates in ASHRAE Standard 170–2008, Section 7; the requirements of the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2); or a local equivalent, whichever is most stringent [Canada ACP]. For any area not covered in 170 or the FGI guidelines, follow ASHRAE 62.1 or a local equivalent, whichever is more stringent and meet the minimum requirements of ASHRAE Standard 170–2008, Sections 6–8, Ventilation of Health Care Facilities (with errata) or a USGBC-approved equivalent standard for projects outside the U.S.
Naturally Ventilated Spaces
For naturally ventilated spaces (and for mixed-mode systems when the mechanical ventilation is inactivated), determine the minimum outdoor air opening and space configuration requirements using the natural ventilation procedure of ASHRAE Standard 62.1–2010 (with errata) or a local equivalent, whichever is more stringent. Confirm that natural ventilation is an effective strategy for the project by following the flow diagram in Figure 2.8 of the Chartered Institution of Building Services Engineers (CIBSE) Applications Manual AM10, March 2005, Natural Ventilation in Nondomestic Buildings. [Latin America ACP: Engineered Natural Ventilation Systems]
Monitoring
Mechanically Ventilated Spaces
For mechanically ventilated spaces (and for mixed-mode systems when the mechanical ventilation is activated), provide a direct outdoor airflow measurement device capable of measuring the minimum outdoor air intake flow. This device must measure the minimum outdoor air intake flow with an accuracy of +/–10% of the design minimum outdoor airflow rate defined by the ventilation requirements above. An alarm must alert staff whenever the outdoor airflow value varies by 15% or more from the outdoor airflow setpoint.
Naturally Ventilated Spaces
For naturally ventilated spaces (and for mixed-mode systems when the mechanical ventilation is inactivated), comply with at least one of the following strategies.
  • Provide a direct exhaust airflow measurement device capable of measuring 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.
  • 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 by using the methods in ASHRAE 62.1–2010, Appendix C.

Alternative Compliance Paths (ACPs)

Canada ACP
Projects in Canada may consider CAN/CSA-Z317.2-10 - Special requirements for heating, ventilation, and air-conditioning (HVAC) systems in health care facilities as an equivalent to ASHRAE Standard 170–2008, Section 7 and the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2).
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). 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

A building has fan-assisted ventilation and no mechanical cooling system. Does this qualify as natural ventilation?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What options are available to mechanically ventilated projects outside the U.S. to meet this prerequisite?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

See all forum discussions about this credit »

Addenda

4/10/2020Updated: 11/12/2020
Regional ACP
Description of change:
Projects in Japan may use JIS filter standard as alternative to ASHRAE 52.2 MERV requirements, as follows:
E(4) 25%, as defined by JIS B 9908:2011 as alternative to MERV 6
E(4) 60%, as defined by JIS B 9908:2011, as alternative to MERV 8
ePM2.5 36%, as defined by JIS B 9908: 2018, as alternative to MERV 11
ePM1 49%, as defiend by JIS B 9908:2018 as alternative to MERV 13
Campus Applicable
No
Internationally Applicable:
Yes
4/5/2016Updated: 1/8/2020
Regional ACP
Description of change:
Under Naturally Ventilated Spaces in the rating system, add the following language: "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)."
Campus Applicable
No
Internationally Applicable:
Yes
7/1/2014Updated: 3/29/2018
Regional ACP
Description of change:
Add the following as a Canada ACP:

"Projects in Canada may consider CAN/CSA-Z317.2-10 - Special requirements for heating, ventilation, and air-conditioning (HVAC) systems in health care facilities as an equivalent to ASHRAE Standard 170–2008, Section 7 and the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2)."
Campus Applicable
No
Internationally Applicable:
Yes
4/1/2015Updated: 4/1/2015
Reference Guide Correction
Description of change:
As of October 2014, a new calculator is available for the Minimum Indoor Air Quality Performance prerequisite. This correction includes the new calculator in the guidance for multiple-zone systems.

1. In Step-by-Step Guidance, Mechanically Ventilated Spaces (and Mixed-Mode Spaces When a Mechanical Ventilation is Active), [BD+C page 611, Step 2; ID+C page 311, Step 2; BO+M page 399, Step 4]
Replace the first sentence in last the bullet with the following: "For multiple-zone systems, use the calculator provided by USGBC or ASHRAE’s 62MZCalc Spreadsheet."

2. In Further Explanation, Calculations for Multiple-Zone Recirculating Systems [BD+C page 617; ID+C page 316; BO+M page 402]
Replace the first paragraph with the following: "Because of the complexity of the calculations for multiple-zone recirculating systems, project teams must use the calculator provided by USGBC, ASHRAE's 62MZCalc spreadsheet, or energy modeling software to perform the ventilation rate procedure calculations and determine the amount of outdoor air required at the system level."

3. In Further Explanation, Calculations for Multiple-Zone Recirculating Systems, System Ventilation Efficiency [BD+C page 617; ID+C page 317; BO+M page 402]
Replace the second and third paragraphs with the following: "The critical zone is the zone with the highest proportion of required outdoor air to provided supply air. Critical zones are often densely occupied spaces, such as conference rooms. If using the calculator provided by USGBC or ASHRAE’s 62MZCalc spreadsheet, when all zones are entered, the critical zone for the system is determined automatically.

For large projects, it may not be feasible to enter each individual zone. In these cases, the mechanical engineer can determine the outdoor air required for the system simply by identifying the potentially critical zone(s). For a detailed discussion of identifying critical zones, see ASHRAE Standard 62.1–2010, Appendix A–A3.1, Selecting Zones for Calculation, and ASHRAE 62.1–2010 User’s Manual, Example 6-L."
Campus Applicable
No
Internationally Applicable:
No
10/1/2014Updated: 2/14/2015
Form Update
Description of change:
New calculator for projects performing the ASHRAE 62.1 ventilation rate procedure calculations required for EQ Prerequisite Minimum Indoor Air Quality Performance. This optional calculator can be used for LEED 2009 and LEED v4 projects and is an alternative to the ASHRAE 62.1 62MZCalc and previous 100% outdoor air and single zone calculators.
Campus Applicable
No
Internationally Applicable:
No
7/8/2017
LEED Interpretation
Inquiry:

We are a residential project with 610 residential units, each of which is independently ventilated with a constant volume ventilation system consisting of an Energy Recovery Ventilator (ERV) that delivers 100% outdoor air. Providing outdoor air intake flow monitors for each system is excessive in this case because for smaller systems, there are no standard manufacturer monitoring device options and it is likely that the occupants of the space would readily recognize system failure. For these reasons, the project team would like to inquire if we are required to meet the monitoring requirements of this prerequisite. If so, are there alternative compliance paths available for residential projects and/or for projects with smaller ventilation systems?

Ruling:

Outdoor air intake flow monitors are not required for small systems (systems with an outdoor air intake flow of not more than 1000 cfm (472 L/s)) if the system is balanced per ASHRAE 62.1-2010, section 7.2.2 and the maintenance plan for EA prerequisite Fundamental commissioning and verification meets the requirements of ASHRAE 62.1-2010, sections 8.4.1.2 and 8.4.1.6 and includes preventative maintenance measures for the system (for example: clean, lubricate, repair, replace, or adjust components as needed).

Campus Applicable
No
Internationally Applicable:
No
7/1/2015
LEED Interpretation
Inquiry:

May we use a more current version of ASHRAE 62.1 and ASHRAE 55?

Ruling:

Yes, for ASHRAE 62.1, LEED v4.1 projects may use ASHRAE 62.1-2019 or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2016 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Enhanced Indoor Air Quality Strategies. The same standard must be used for both credits.

LEED v4 projects may use ASHRAE 62.1-2013, ASHRAE 62.1-2016, ASHRAE 62.1-2019, or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2010 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Enhanced Indoor Air Quality Strategies. The same standard must be used for both credits.

LEED 2009 projects may use ASHRAE 62.1-2010, ASHRAE 62.1-2013, or ASHRAE 62.1-2016, ASHRAE 62.1-2019, or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2007 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Increased Ventilation. The same standard must be used for both credits.

For ASHRAE 55, LEED v4.1 projects may use ASHRAE 55-2020 in lieu of ASHRAE 55-2017 for EQ Credit Thermal Comfort. 

LEED v4 projects may use ASHRAE 55-2013 in lieu of ASHRAE 55-2010 for EQ Credit Thermal Comfort. 

LEED 2009 projects may use ASHRAE 55-2010 or ASHRAE 55-2013 in lieu of ASHRAE 55-2004 for EQ Credit Thermal Comfort- Design.

**Updated 7/10/2020 to include ASHRAE 62.1-2016 and ASHRAE 62.1-2019 as applicable standards.**

**Updated 7/25/2023 to update to include LEED v4.1 and ASHRAE 2022/2020 standards**

Campus Applicable
No
Internationally Applicable:
No
4/9/2019
LEED Interpretation
Inquiry:

We are trying to meet the ventilation requirements for mechanically ventilated spaces via ASHRAE 62.1.-2010. It is common for buildings in our region to employ ceiling mounted VRF systems or fan coil units at perimeter zones, however, it is highly uncommon to install filters on VRF interior units or small size AC units, so a majority of manufacturers do not provide interior equipment that allows the installation of filters equivalent to MERV 6.

It is unrealistic to require MERV 6 filters for all small air flow systems due to maintenance issues for these smaller systems. Is there an alternate path available for projects with smaller ventilation systems to comply with the particulate matter filtration requirements for this prerequisite?

Ruling:

Yes, for the EQ prerequisite Minimum indoor air quality performance, small indoor fan coils such as VRF fan coils can be exempted from the ASHRAE 62.1-2010 Section 5.8 or ASHRAE 62.1-2007 Section 5.9 particulate matter removal requirements subject to the following constraints:

1. The fan coil may not introduce outside air directly from the outdoors. The fan coil must either be a 100% recirculating system, or have outside air delivered from a Dedicated Outside air system that filters the outside air.
2. The fan coil cooling capacity must not exceed 30,000 Btuh (9 kW)

Campus Applicable
No
Internationally Applicable:
Yes
10/1/2012
LEED Interpretation
Inquiry:

We are meeting the IEQp1: Minimum Indoor Air Quality Performance with Option 2, CEN standards EN 15251:2007 and EN 13779:2007. The CEN standards provide minimum outdoor air requirements for most spaces but refer to local codes for certain specialty spaces such as parking garages. To meet the intent of the prerequisite, we propose using our local code requirements for garages, which is Teil 5 Garagen (“Section 5 – Parking Garages”) of the Verordnung über Bau und Betrieb von Sonderbauten - Nordrhein-Westfalen (“Local Law of North Rhine-Westphalia for the Construction and Operation of Specialty Buildings”), dated 17 November 2009 (SBauVO). To meet this local code, our design will use demand control ventilation with carbon monoxide (CO) detectors to limit the CO concentration. Is this approach acceptable?

Ruling:

**Update 10/01/2014: Ruling has been revised
Yes, garage demand control ventilation is an acceptable ventilation approach for parking garages. This approach is acceptable for projects pursuing Option 2 (EN 15251 and EN 13779) of EQ Prerequisite Minimum Indoor Air Quality Performance as well as the hazardous exhaust requirements in EQ Credit Indoor Chemical and Pollutant Source Control. The demand control ventilation strategy must meet the following requirements:

  • • Consider the number of cars expected to be operating in the garage at any given time and the length of time a car remains in operation in the parking garage.
  • • Consider the emission rates associated with the car exhaust for the average car.
  • • Detect the primary contaminant(s) of concern in the parking garage (for example: carbon monoxide, particulates, VOCs, NO2, etc.).
  • • Modulate airflow such that contaminant levels are maintained below a specified contaminant concentration limit and corresponding exposure period. All concentration limits must be based on local code or some other cognizant authority. If the contaminant is carbon monoxide, a concentration limit of 35 ppm time-weighted average (8 hours) and levels not to exceed 50 ppm at any time is recommended.
Campus Applicable
No
Internationally Applicable:
Yes
See all forum discussions about this credit »

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© Copyright U.S. Green Building Council, Inc. All rights reserved.

Requirements

Meet the following requirements for both ventilation and monitoring.

Ventilation
Mechanically Ventilated Spaces
For mechanically ventilated spaces (and for mixed-mode systems when the mechanical ventilation is activated), determine the minimum outdoor air intake flow for mechanical ventilations systems using the ventilation rates in ASHRAE Standard 170–2008, Section 7; the requirements of the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2); or a local equivalent, whichever is most stringent [Canada ACP]. For any area not covered in 170 or the FGI guidelines, follow ASHRAE 62.1 or a local equivalent, whichever is more stringent and meet the minimum requirements of ASHRAE Standard 170–2008, Sections 6–8, Ventilation of Health Care Facilities (with errata) or a USGBC-approved equivalent standard for projects outside the U.S.
Naturally Ventilated Spaces
For naturally ventilated spaces (and for mixed-mode systems when the mechanical ventilation is inactivated), determine the minimum outdoor air opening and space configuration requirements using the natural ventilation procedure of ASHRAE Standard 62.1–2010 (with errata) or a local equivalent, whichever is more stringent. Confirm that natural ventilation is an effective strategy for the project by following the flow diagram in Figure 2.8 of the Chartered Institution of Building Services Engineers (CIBSE) Applications Manual AM10, March 2005, Natural Ventilation in Nondomestic Buildings. [Latin America ACP: Engineered Natural Ventilation Systems]
Monitoring
Mechanically Ventilated Spaces
For mechanically ventilated spaces (and for mixed-mode systems when the mechanical ventilation is activated), provide a direct outdoor airflow measurement device capable of measuring the minimum outdoor air intake flow. This device must measure the minimum outdoor air intake flow with an accuracy of +/–10% of the design minimum outdoor airflow rate defined by the ventilation requirements above. An alarm must alert staff whenever the outdoor airflow value varies by 15% or more from the outdoor airflow setpoint.
Naturally Ventilated Spaces
For naturally ventilated spaces (and for mixed-mode systems when the mechanical ventilation is inactivated), comply with at least one of the following strategies.
  • Provide a direct exhaust airflow measurement device capable of measuring 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.
  • 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 by using the methods in ASHRAE 62.1–2010, Appendix C.

Alternative Compliance Paths (ACPs)

Canada ACP
Projects in Canada may consider CAN/CSA-Z317.2-10 - Special requirements for heating, ventilation, and air-conditioning (HVAC) systems in health care facilities as an equivalent to ASHRAE Standard 170–2008, Section 7 and the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2).
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).

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 »

In the end, LEED is all about documentation. LEEDuser’s Documentation Toolkit, for premium members only, saves you time and helps you avoid mistakes with:

  • Calculators to help assess credit compliance.
  • Tracking spreadsheets for materials purchases.
  • Spreadsheets and forms to give to subs and other team members.
  • Guidance documents on arcane LEED issues.
  • Sample templates to help guide your narratives and LEED Online submissions.
  • Examples of actual submissions from certified LEED projects.

A building has fan-assisted ventilation and no mechanical cooling system. Does this qualify as natural ventilation?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

What options are available to mechanically ventilated projects outside the U.S. to meet this prerequisite?

The answer to this question is available to LEEDuser premium members. Start a free trial »

(If you're already a premium member, log in here.)

4/10/2020Updated: 11/12/2020
Regional ACP
Description of change:
Projects in Japan may use JIS filter standard as alternative to ASHRAE 52.2 MERV requirements, as follows:
E(4) 25%, as defined by JIS B 9908:2011 as alternative to MERV 6
E(4) 60%, as defined by JIS B 9908:2011, as alternative to MERV 8
ePM2.5 36%, as defined by JIS B 9908: 2018, as alternative to MERV 11
ePM1 49%, as defiend by JIS B 9908:2018 as alternative to MERV 13
Campus Applicable
No
Internationally Applicable:
Yes
4/5/2016Updated: 1/8/2020
Regional ACP
Description of change:
Under Naturally Ventilated Spaces in the rating system, add the following language: "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)."
Campus Applicable
No
Internationally Applicable:
Yes
7/1/2014Updated: 3/29/2018
Regional ACP
Description of change:
Add the following as a Canada ACP:

"Projects in Canada may consider CAN/CSA-Z317.2-10 - Special requirements for heating, ventilation, and air-conditioning (HVAC) systems in health care facilities as an equivalent to ASHRAE Standard 170–2008, Section 7 and the 2010 FGI Guidelines for Design and Construction of Health Care Facilities (Table 2.1–2)."
Campus Applicable
No
Internationally Applicable:
Yes
4/1/2015Updated: 4/1/2015
Reference Guide Correction
Description of change:
As of October 2014, a new calculator is available for the Minimum Indoor Air Quality Performance prerequisite. This correction includes the new calculator in the guidance for multiple-zone systems.

1. In Step-by-Step Guidance, Mechanically Ventilated Spaces (and Mixed-Mode Spaces When a Mechanical Ventilation is Active), [BD+C page 611, Step 2; ID+C page 311, Step 2; BO+M page 399, Step 4]
Replace the first sentence in last the bullet with the following: "For multiple-zone systems, use the calculator provided by USGBC or ASHRAE’s 62MZCalc Spreadsheet."

2. In Further Explanation, Calculations for Multiple-Zone Recirculating Systems [BD+C page 617; ID+C page 316; BO+M page 402]
Replace the first paragraph with the following: "Because of the complexity of the calculations for multiple-zone recirculating systems, project teams must use the calculator provided by USGBC, ASHRAE's 62MZCalc spreadsheet, or energy modeling software to perform the ventilation rate procedure calculations and determine the amount of outdoor air required at the system level."

3. In Further Explanation, Calculations for Multiple-Zone Recirculating Systems, System Ventilation Efficiency [BD+C page 617; ID+C page 317; BO+M page 402]
Replace the second and third paragraphs with the following: "The critical zone is the zone with the highest proportion of required outdoor air to provided supply air. Critical zones are often densely occupied spaces, such as conference rooms. If using the calculator provided by USGBC or ASHRAE’s 62MZCalc spreadsheet, when all zones are entered, the critical zone for the system is determined automatically.

For large projects, it may not be feasible to enter each individual zone. In these cases, the mechanical engineer can determine the outdoor air required for the system simply by identifying the potentially critical zone(s). For a detailed discussion of identifying critical zones, see ASHRAE Standard 62.1–2010, Appendix A–A3.1, Selecting Zones for Calculation, and ASHRAE 62.1–2010 User’s Manual, Example 6-L."
Campus Applicable
No
Internationally Applicable:
No
10/1/2014Updated: 2/14/2015
Form Update
Description of change:
New calculator for projects performing the ASHRAE 62.1 ventilation rate procedure calculations required for EQ Prerequisite Minimum Indoor Air Quality Performance. This optional calculator can be used for LEED 2009 and LEED v4 projects and is an alternative to the ASHRAE 62.1 62MZCalc and previous 100% outdoor air and single zone calculators.
Campus Applicable
No
Internationally Applicable:
No
7/8/2017
LEED Interpretation
Inquiry:

We are a residential project with 610 residential units, each of which is independently ventilated with a constant volume ventilation system consisting of an Energy Recovery Ventilator (ERV) that delivers 100% outdoor air. Providing outdoor air intake flow monitors for each system is excessive in this case because for smaller systems, there are no standard manufacturer monitoring device options and it is likely that the occupants of the space would readily recognize system failure. For these reasons, the project team would like to inquire if we are required to meet the monitoring requirements of this prerequisite. If so, are there alternative compliance paths available for residential projects and/or for projects with smaller ventilation systems?

Ruling:

Outdoor air intake flow monitors are not required for small systems (systems with an outdoor air intake flow of not more than 1000 cfm (472 L/s)) if the system is balanced per ASHRAE 62.1-2010, section 7.2.2 and the maintenance plan for EA prerequisite Fundamental commissioning and verification meets the requirements of ASHRAE 62.1-2010, sections 8.4.1.2 and 8.4.1.6 and includes preventative maintenance measures for the system (for example: clean, lubricate, repair, replace, or adjust components as needed).

Campus Applicable
No
Internationally Applicable:
No
7/1/2015
LEED Interpretation
Inquiry:

May we use a more current version of ASHRAE 62.1 and ASHRAE 55?

Ruling:

Yes, for ASHRAE 62.1, LEED v4.1 projects may use ASHRAE 62.1-2019 or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2016 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Enhanced Indoor Air Quality Strategies. The same standard must be used for both credits.

LEED v4 projects may use ASHRAE 62.1-2013, ASHRAE 62.1-2016, ASHRAE 62.1-2019, or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2010 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Enhanced Indoor Air Quality Strategies. The same standard must be used for both credits.

LEED 2009 projects may use ASHRAE 62.1-2010, ASHRAE 62.1-2013, or ASHRAE 62.1-2016, ASHRAE 62.1-2019, or ASHRAE 62.1-2020 in lieu of ASHRAE 62.1-2007 for EQ Prerequisite Minimum Indoor Air Quality Performance and EQ Credit Increased Ventilation. The same standard must be used for both credits.

For ASHRAE 55, LEED v4.1 projects may use ASHRAE 55-2020 in lieu of ASHRAE 55-2017 for EQ Credit Thermal Comfort. 

LEED v4 projects may use ASHRAE 55-2013 in lieu of ASHRAE 55-2010 for EQ Credit Thermal Comfort. 

LEED 2009 projects may use ASHRAE 55-2010 or ASHRAE 55-2013 in lieu of ASHRAE 55-2004 for EQ Credit Thermal Comfort- Design.

**Updated 7/10/2020 to include ASHRAE 62.1-2016 and ASHRAE 62.1-2019 as applicable standards.**

**Updated 7/25/2023 to update to include LEED v4.1 and ASHRAE 2022/2020 standards**

Campus Applicable
No
Internationally Applicable:
No
4/9/2019
LEED Interpretation
Inquiry:

We are trying to meet the ventilation requirements for mechanically ventilated spaces via ASHRAE 62.1.-2010. It is common for buildings in our region to employ ceiling mounted VRF systems or fan coil units at perimeter zones, however, it is highly uncommon to install filters on VRF interior units or small size AC units, so a majority of manufacturers do not provide interior equipment that allows the installation of filters equivalent to MERV 6.

It is unrealistic to require MERV 6 filters for all small air flow systems due to maintenance issues for these smaller systems. Is there an alternate path available for projects with smaller ventilation systems to comply with the particulate matter filtration requirements for this prerequisite?

Ruling:

Yes, for the EQ prerequisite Minimum indoor air quality performance, small indoor fan coils such as VRF fan coils can be exempted from the ASHRAE 62.1-2010 Section 5.8 or ASHRAE 62.1-2007 Section 5.9 particulate matter removal requirements subject to the following constraints:

1. The fan coil may not introduce outside air directly from the outdoors. The fan coil must either be a 100% recirculating system, or have outside air delivered from a Dedicated Outside air system that filters the outside air.
2. The fan coil cooling capacity must not exceed 30,000 Btuh (9 kW)

Campus Applicable
No
Internationally Applicable:
Yes
10/1/2012
LEED Interpretation
Inquiry:

We are meeting the IEQp1: Minimum Indoor Air Quality Performance with Option 2, CEN standards EN 15251:2007 and EN 13779:2007. The CEN standards provide minimum outdoor air requirements for most spaces but refer to local codes for certain specialty spaces such as parking garages. To meet the intent of the prerequisite, we propose using our local code requirements for garages, which is Teil 5 Garagen (“Section 5 – Parking Garages”) of the Verordnung über Bau und Betrieb von Sonderbauten - Nordrhein-Westfalen (“Local Law of North Rhine-Westphalia for the Construction and Operation of Specialty Buildings”), dated 17 November 2009 (SBauVO). To meet this local code, our design will use demand control ventilation with carbon monoxide (CO) detectors to limit the CO concentration. Is this approach acceptable?

Ruling:

**Update 10/01/2014: Ruling has been revised
Yes, garage demand control ventilation is an acceptable ventilation approach for parking garages. This approach is acceptable for projects pursuing Option 2 (EN 15251 and EN 13779) of EQ Prerequisite Minimum Indoor Air Quality Performance as well as the hazardous exhaust requirements in EQ Credit Indoor Chemical and Pollutant Source Control. The demand control ventilation strategy must meet the following requirements:

  • • Consider the number of cars expected to be operating in the garage at any given time and the length of time a car remains in operation in the parking garage.
  • • Consider the emission rates associated with the car exhaust for the average car.
  • • Detect the primary contaminant(s) of concern in the parking garage (for example: carbon monoxide, particulates, VOCs, NO2, etc.).
  • • Modulate airflow such that contaminant levels are maintained below a specified contaminant concentration limit and corresponding exposure period. All concentration limits must be based on local code or some other cognizant authority. If the contaminant is carbon monoxide, a concentration limit of 35 ppm time-weighted average (8 hours) and levels not to exceed 50 ppm at any time is recommended.
Campus Applicable
No
Internationally Applicable:
Yes

LEEDuser expert

Ben Stanley

WSP - Built Ecology
Senior Sustainability Manager

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