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LEED v4
Schools – New Construction
Indoor Environmental Quality

Indoor air quality assessment

LEED CREDIT

Schools-NC-v4 EQc4: Indoor air quality assessment 1-2 points

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Requirements

Select one of the following two options, to be implemented after construction ends and the building has been completely cleaned. All interior finishes, such as millwork, doors, paint, carpet, acoustic tiles, and movable furnishings (e.g., workstations, partitions), must be installed, and major VOC punch list items must be finished. The options cannot be combined.

Option 1. Flush-out (1 point)
Path 1. Before occupancy
Install new filtration media and perform a building flush-out by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot (4 267 140 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%.

OR

Path 2. During occupancy
If occupancy is desired before the flush-out is completed, the space may be occupied only after delivery of a minimum of 3,500 cubic feet of outdoor air per square foot (1 066 260 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic foot per minute (cfm) per square foot of outdoor air (1.5 liters per second per square meter of outdoor air) or the design minimum outdoor air rate determined in EQ Prerequisite Minimum Indoor Air Quality Performance, whichever is greater. During each day of the flush-out period, ventilation must begin at least three hours before occupancy and continue during occupancy. These conditions must be maintained until a total of 14,000 cubic feet per square foot of outdoor air (4 267 140 liters of outdoor air per square meter) has been delivered to the space.

OR

Option 2. Air testing (2 points)
After construction ends and before occupancy, but under ventilation conditions typical for occupancy, conduct baseline IAQ testing using protocols consistent with the methods listed in Table 1 for all occupied spaces. Use current versions of ASTM standard methods, EPA compendium methods, or ISO methods, as indicated. Laboratories that conduct the tests for chemical analysis of formaldehyde and volatile organic compounds must be accredited under ISO/IEC 17025 for the test methods they use. Retail projects may conduct the testing within 14 days of occupancy. Demonstrate that contaminants do not exceed the concentration levels listed in Table 1.
Table 1. Maximum concentration levels, by contaminant and testing method
click the link to view full table Conduct all measurements before occupancy but during normal occupied hours, with the building ventilation system started at the normal daily start time and operated at the minimum outdoor airflow rate for the occupied mode throughout the test. For each sampling point where the concentration exceeds the limit, take corrective action and retest for the noncompliant contaminants at the same sampling points. Repeat until all requirements are met. See all forum discussions about this credit »

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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 »

Addenda

7/2/2018 – Updated: 8/10/2018
Reference Guide Correction
Description of change:
Replace the text under Step 1. Determine Air-Testing Location with the following:

"Determine where in the building IAQ testing will be performed.

First, perform an initial analysis to identify potential locations to test in the building. Consider locations that are most representative of the building space, and where occupants will normally spend their time.
• Identify at least one location per ventilation system. Include locations that represent the worst-case zones where the highest concentrations of contaminants of concern are likely to occur.
• Identify at least one location per floor of the building.
• Identify at least one location per space type. In most cases, only regularly occupied spaces need to be included. Additionally, for each space type identified, if the air is not well mixed or contaminants are not expected to be uniform throughout the space include more than one location in the space for testing.

Next, determine whether a sampling protocol can be used to reduce the number of testing locations identified in the initial analysis. A sampling protocol is particularly useful if the project has many floors or a large number of ventilation systems.
• Identify and group spaces (or floors) that are very similar in their construction, finishes, configuration, size, and HVAC systems.
• Randomly select one out of every seven very similar spaces to include in the testing. In addition, for buildings with a large number of identical spaces (more than 21 spaces in a sample group), test a minimum of three spaces in the sample group."


Under Step 2. Perform Test, add the following to the first paragraph, after the second sentence:
"If a test fails and a sampling protocol was used, conduct re-testing to assess whether the failure is unique or the rest of the spaces are likely to have similar failings."
Campus Applicable
No
Internationally Applicable:
No
7/1/2014 – Updated: 7/9/2018
Rating System Correction
Description of change:
Modify the SI unit conversions:
Path 1, change 4 267 140 liters per second of outdoor air per square meter' to '4 267 140 liters of outdoor air per square meter'.
Path 2, change '1 066 260 liters per second of outdoor air per square meter' to '1 066 260 liters of outdoor air per square meter'.
Path 2, change ‘1.5 liters of outside air per second per square meter’ to ‘1.5 liters per second per square meter of outdoor air’.
Path 2, change ‘4 270 cubic meters of outdoor air per square meter’ to ‘4 267 140 liters of outdoor air per square meter’.

Behind the intent, in third paragraph, add SI for airflow rate so reads ‘0.7 cubic feet per minute per square foot (3.55 liters per second per square meter)’

Behind the intent image/calculation change ‘4 294 080 lps’ to ‘4 294 080 l’

Equation 1, change ‘14,000 cfm’ to ‘14,000 ft3/ft2’ and ‘4 267 140 lps’ to ‘4 267 140 l/m2’
Equation 2, change ‘3,500 cfm of outdoor air’ to ‘3,500 ft3/ft2’ and ‘1 066 260 lps’ to 1 066 260 l/m2’
Equation 3, change ’10,500 cfm’ to ’10,500 ft3/ft2’ and 3 200 880 lps’ to ‘3 200 880 l/m2’
Equation ,4 change ‘14,000 cfm’ to ‘14,000 ft3/ft2’ and ‘4 267 140 lps’ to ‘4 267 140 l/m2’

Table 2, change column header to Total Outdoor Air Required (ft3/ft2)
Table 3, change column header to Total Outdoor Air Required (l/m2)
Table 4, change column header to ‘Total outdoor air required before occupancy (cfm/ft2)' and column header to ‘Total outdoor air required to complete flush-out (ft3/ft2),
and modify volume of air required to complete flush out (ft3) if applicable.
Table 5, change column header from ‘Total outdoor air required before occupancy (l/m2)' and column header to ‘Total outdoor air required to complete flush-out (l/m2).

**updated July 8 2017 to fix SI unit conversion for path 2 ('4 267 140 liters of outdoor air per square meter').

**updated July 2, 2018:
"Under Further explanation, examples, Tables 2, 3, 4, & 5 change column header from "net office area" to "gross floor area"

Campus Applicable
Yes
Internationally Applicable:
Yes
7/1/2014 – Updated: 7/9/2018
Reference Guide Correction
Description of change:
Modify the SI unit conversions:
Path 1, change 4 267 140 liters per second of outdoor air per square meter' to '4 267 140 liters of outdoor air per square meter'.
Path 2, change '1 066 260 liters per second of outdoor air per square meter' to '1 066 260 liters of outdoor air per square meter'.
Path 2, change ‘1.5 liters of outside air per second per square meter’ to ‘1.5 liters per second per square meter of outdoor air’.
Path 2, change ‘4 270 cubic meters of outdoor air per square meter’ to ‘4 267 140 liters of outdoor air per square meter’.

Behind the intent, in third paragraph, add SI for airflow rate so reads ‘0.7 cubic feet per minute per square foot (3.55 liters per second per square meter)’

Behind the intent image/calculation change ‘4 294 080 lps’ to ‘4 294 080 l’

Equation 1, change ‘14,000 cfm’ to ‘14,000 ft3/ft2’ and ‘4 267 140 lps’ to ‘4 267 140 l/m2’
Equation 2, change ‘3,500 cfm of outdoor air’ to ‘3,500 ft3/ft2’ and ‘1 066 260 lps’ to 1 066 260 l/m2’
Equation 3, change ’10,500 cfm’ to ’10,500 ft3/ft2’ and 3 200 880 lps’ to ‘3 200 880 l/m2’
Equation ,4 change ‘14,000 cfm’ to ‘14,000 ft3/ft2’ and ‘4 267 140 lps’ to ‘4 267 140 l/m2’

Table 2, change column header to Total Outdoor Air Required (ft3/ft2)
Table 3, change column header to Total Outdoor Air Required (l/m2)
Table 4, change column header to ‘Total outdoor air required before occupancy (cfm/ft2)' and column header to ‘Total outdoor air required to complete flush-out (ft3/ft2),
and modify volume of air required to complete flush out (ft3) if applicable.
Table 5, change column header from ‘Total outdoor air required before occupancy (l/m2)' and column header to ‘Total outdoor air required to complete flush-out (l/m2).

**updated July 8 2017 to fix SI unit conversion for path 2 ('4 267 140 liters of outdoor air per square meter').

**updated July 2, 2018:
"Under Further explanation, examples, Tables 2, 3, 4, & 5 change column header from "net office area" to "gross floor area"

Campus Applicable
Yes
Internationally Applicable:
Yes
10/1/2015 – Updated: 6/29/2017
Rating System Correction
Description of change:
Revise Table 1 as follows:

1. Remove TO-15 from "ASTM and U.S. EPA methods" column
2. Add the full list of target chemicals, except formaldehyde, from CDPH Standard Method v1.1 in place of the single row (Target chemicals listed in CDPH Standard Method v1.1, Table 4.1, except formaldehyde) and revise the Maximum concentrations from CDPH Standard Method v1.1 2010, Allowable Concentrations, Table 4-1 with the Cal/EPA OEHHA full CREL in effect on June 2014.
3. reformat table for clarity
Campus Applicable
No
Internationally Applicable:
Yes
1/27/2017 – Updated: 1/27/2017
Reference Guide Correction
Description of change:
Step 3, revise last bullet to "Complete testing and balancing of the HVAC system before testing."
Step 4, revise first sentence to "Thoroughly clean the building, including the ductwork, before testing or beginning a flush-out." revise second bullet to "Consider using low-emitting cleaning products...", and revise third bullet to "consider using vacuum cleaners with HEPA..."
Campus Applicable
No
Internationally Applicable:
No
10/1/2015 – Updated: 12/16/2015
Reference Guide Correction
Description of change:
In Step 2, replace the last bullet with the following: Testing must be performed by an appropriately accredited professional, using the approved test methods. The accredited professional should determine the sampling time based on the test method, maximum allowable concentration, and expert judgment.

In Changes from LEED 2009, add a final bullet: There is no longer a 4-hour sampling time requirement in Option 2.
Campus Applicable
No
Internationally Applicable:
No
7/1/2014 – Updated: 2/14/2015
Form Update
Description of change:
Under Option 1, Path 2, removed checkbox, "New filtration media were installed before the flush-out began."
Campus Applicable
Yes
Internationally Applicable:
Yes
7/1/2015
LEED Interpretation
Inquiry:

For Option 2, Air Testing, can ISO 16000-4 be used to test for formaldehyde?

Ruling:

Yes, ISO 16000-4 is an acceptable test method for formaldehyde.

Campus Applicable
No
Internationally Applicable:
No
See all forum discussions about this credit »

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Requirements

Select one of the following two options, to be implemented after construction ends and the building has been completely cleaned. All interior finishes, such as millwork, doors, paint, carpet, acoustic tiles, and movable furnishings (e.g., workstations, partitions), must be installed, and major VOC punch list items must be finished. The options cannot be combined.

Option 1. Flush-out (1 point)
Path 1. Before occupancy
Install new filtration media and perform a building flush-out by supplying a total air volume of 14,000 cubic feet of outdoor air per square foot (4 267 140 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%.

OR

Path 2. During occupancy
If occupancy is desired before the flush-out is completed, the space may be occupied only after delivery of a minimum of 3,500 cubic feet of outdoor air per square foot (1 066 260 liters of outdoor air per square meter) of gross floor area while maintaining an internal temperature of at least 60°F (15°C) and no higher than 80°F (27°C) and relative humidity no higher than 60%. Once the space is occupied, it must be ventilated at a minimum rate of 0.30 cubic foot per minute (cfm) per square foot of outdoor air (1.5 liters per second per square meter of outdoor air) or the design minimum outdoor air rate determined in EQ Prerequisite Minimum Indoor Air Quality Performance, whichever is greater. During each day of the flush-out period, ventilation must begin at least three hours before occupancy and continue during occupancy. These conditions must be maintained until a total of 14,000 cubic feet per square foot of outdoor air (4 267 140 liters of outdoor air per square meter) has been delivered to the space.

OR

Option 2. Air testing (2 points)
After construction ends and before occupancy, but under ventilation conditions typical for occupancy, conduct baseline IAQ testing using protocols consistent with the methods listed in Table 1 for all occupied spaces. Use current versions of ASTM standard methods, EPA compendium methods, or ISO methods, as indicated. Laboratories that conduct the tests for chemical analysis of formaldehyde and volatile organic compounds must be accredited under ISO/IEC 17025 for the test methods they use. Retail projects may conduct the testing within 14 days of occupancy. Demonstrate that contaminants do not exceed the concentration levels listed in Table 1.
Table 1. Maximum concentration levels, by contaminant and testing method
click the link to view full table Conduct all measurements before occupancy but during normal occupied hours, with the building ventilation system started at the normal daily start time and operated at the minimum outdoor airflow rate for the occupied mode throughout the test. For each sampling point where the concentration exceeds the limit, take corrective action and retest for the noncompliant contaminants at the same sampling points. Repeat until all requirements are met.

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.

LEEDuser expert

headshot

gaspar cabrera

See all LEEDuser forum discussions about this credit » Subscribe to new discussions about Schools-NC-v4 EQc4 View the LEED v4.1 version of this credit