Executive Order 13423 Technical Guidance - Protect Indoor Air Quality During Construction
General Principles and Commitments
Follow the recommended approach of the Sheet Metal and Air Conditioning Contractor's National Association Indoor Air Quality Guidelines for Occupied Buildings under Construction, 1995. After construction and prior to occupancy, conduct a minimum 72-hour flush-out with maximum outdoor air consistent with achieving relative humidity no greater than 60 percent. After occupancy, continue flush-out as necessary to minimize exposure to contaminants from new building materials.
Technical Guidance
Introduction
The construction process generates a host of particulate and gaseous pollutants that can contaminate building elements and ultimately affect the IEQ of the finished building. This is the result of both construction activities and the use of products that may emit significant levels of contaminants. In addition, many building elements may become wet from rain or snow, thus increasing the potential for mold contamination. Construction IEQ procedures need to be developed to minimize contamination from these sources, and to prepare the building for safe occupancy.
Follow the recommended Design Approaches of the Sheet Metal and Air Conditioning National Contractors Association (SMACNA) IAQ Guideline for Occupied Buildings under Construction, 1995, Chapter 3, and develop and implement an Indoor Environmental Quality Management Plan for the construction and pre-occupancy phases of the building in accordance with the Sheet Metal and Air Conditioning National Contractors Association (SMACNA) IAQ Criteria for Occupied Buildings under Construction, 1995, Chapter 4.
The Federal Green Construction Guide for Specifiers provides model guide spec language to assist agencies in meeting these requirements.
Additional Considerations
Protect stored on-site or installed absorptive materials from rain, snow, and other water sources.
If air handlers must be used during construction, filtration media with a Minimum Efficiency Reporting Value (MERV) of 8 must be used at each return air grill, as determined by the current ASHRAE 52.2.
Seal all ducts and plenums that service the work zone but are not used during construction with plastic to prevent contamination of the HVAC system.
Sequence the application of building materials so that the emissions from materials that may be significant sources of contaminants are significantly depleted before products with the capacity to absorb or trap contaminants are introduced to the building.
After construction ends and prior to occupancy, conduct a minimum two-week building flush-out at 100% outside air (or maximum outdoor air while achieving a relative humidity not greater than 60%), for 24 hours a day;
OR
After construction ends and prior to occupancy, conduct a minimum three-day building flush-out at 100% outside air (or maximum outdoor air while achieving a relative humidity not greater than 60%). After the flush-out, replace the filtration media, and continue maximum outdoor air (may be during occupancy) for a subsequent period of not less than 30 days using 100% outdoor air, or, if occupants are present, maximum percent outdoor air consistent with achieving thermal comfort and humidity control.
After the flush-out, replace all filtration media prior to occupancy and after any flush-out period after occupancy.
Major Resources
WBDG
Design Objectives
Sustainable—Enhance Indoor Environmental Quality
Model Contract and Specification Language
- Multiple Guide Spec Sections in Federal Green Construction Guide for Specifiers
Publications
- Good Practice Guidelines for Maintaining Acceptable Indoor Environmental Quality During Construction and Renovation Projects, National Institute for Occupational Safety and Health, November 2005.
