Exposure to fine particulate matter (PM2.5) has been identified as a significant public health issue. PM2.5 of outdoor origin accounts for around 50% of indoor PM2.5. Reductions in exposure to PM2.5 of both outdoor and indoor origin can be made in new and existing residential buildings. The practicality of reducing indoor exposures to PM2.5 of outdoor origin by applying airtightness in combination with filtered outdoor air to slightly pressurize new and existing residential buildings is discussed. Potential reductions of exposure to cooking related PM2.5 by applying the information to the design and installation of range hoods is also discussed.

We will summarize the content of a Residential IAQ Guide ASHRAE is developing, scheduled for release in 2017. It will serve as guidance for achieving good IAQ through source control, ventilation and air cleaning. Principles are based on research findings “boiled down” to actionable and concrete form.

The presentation addresses all who influence the residential environment: architects, engineers, homebuilders, construction contractors; quality control professionals (commissioning); organizations; homeowners, residents and operators. This new publication supplements Indoor Air Quality Guide: Best Practices for Design, Construction and Commissioning, published in 2009, which was targeted primarily a non-residential audience.

Time-resolved concentrations of nitrogen dioxide (NO₂) and particles were measured during and after scripted use of natural gas cooking burners in 9 California residences. Cooktop, oven, and broiler burners were operated to simulate food preparation. In most homes, the highest NO₂ concentrations in the kitchen exceeded the US EPA’s standard of 100 ppb. Highest 1h concentrations of NO, NO2, and particles in a distant location were often 50% or less of those in the kitchen. Use of venting range hoods substantially reduced concentrations in all 5 homes in which they were tested, though effectiveness varied greatly.

In this presentation, we give an overview of ventilation in new New Zealand houses. At least 10% of New Zealand houses have a positive pressure mechanical ventilation system installed, generally pulling air from the roofspace cavity into the living spaces. We will discuss an in depth measurement and modelling study of two newer houses of timber frame construction with brick cladding and a corrugated iron roof that had positive pressure mechanical ventilation systems installed. The implications of moisture transfer from roofspaces into living spaces and of moisture condensation in houses with positive pressure mechanical ventilation systems will be discussed.

The Healthy Efficient New Gas Homes (HENGH) study is gathering field data from new California homes that use natural gas and are built to 2008 Title 24 standards. Mechanical ventilation is required, so that the reduction in air infiltration and duct leakage needed to save energy will not result in negative health impacts due to decreased dilution of indoor pollutants with outdoor air. This presentation describes results from two research efforts leading to the field study: (1) an online survey with questions about ventilation and IAQ, and (2) a pilot test in two new homes that have mechanical ventilation.

Balancing IAQ and energy savings in exhaust systems have a direct relationship in multifamily high rise buildings. Since there has been little attention on the quality construction of exhaust systems, retrofitting them for current compliance in today's environment can not be done without a baseline of field conditions . This program focuses on the real world challenges, issues and approaches to a key component of multi-family buildings often overlooked.

The Population Impact Assessment Modeling Framework (PIAMF) was developed to quantify the energy and health impacts of changes to the U.S. housing stock. PIAMF calculates one or more environmental and energy performance parameters for each home in a sample of 50,000 homes representing the U.S. housing stock. This presentation gives an overview on applications of PIAMF to develop guidance for cost-effective, energy-efficient methods to reduce indoor exposure to PM2.5. Previous applications have assessed the energy impacts of range hood use, building tightening for the U.S. housing stock, and the exposure impacts of natural gas cooking in Southern California.

We evaluated nine combinations of ventilation and air cleaning systems for pollutant removal and energy use. Systems included supply, exhaust, and balanced ventilation; filtration on ventilation supply and on recirculating FAU; filters with varying MERV ratings; and three VOC air cleaning technologies. All were installed in an unoccupied 2006 house located 250m downwind of I80 in Sacramento, and evaluated for effectiveness at reducing outdoor particles in summer and fall/winter, ozone and VOCs in summer, and indoor particles generated from cooking. Energy use of the systems was estimated for year-round operation in varied California climates.

By all estimates, the enormous problems and massive financial impact associated with leaky ventilation and ductwork have been tolerated for one primary reason - there has been no viable solution to the problem. In 2008, innovative new technologies were used to complete the first comprehensive ventilation retrofit for improving both energy and indoor air quality performance. Since the completion of this retrofit project, thousands of similar multifamily apartments with central ventilation have been retrofitted for higher energy performance and improved indoor air quality.

We investigated the indoor air quality of a low-energy, high-performance deployable structure for use by the U.S. Army on contingency bases overseas.  Results of measurements of volatile organic compounds, carbon dioxide, particulate matter, and air exchange rate under varying conditions are reported and compared to health-based criteria.  In addition, source emission rates of target pollutants are reported, as well as a minimum ventilation rate to maintain acceptable air quality.  Finally, we propose a pre-occupancy protocol for minimizing later VOC exposure.

While most discussions of high performance buildings include site impacts, water use, energy, materials and indoor environmental quality, energy often receives more attention than these other attributes. Given that buildings exist primarily for the occupants, indoor air quality (IAQ) within these buildings obviously merits serious consideration. ASHRAE/IES/USGBC Standard 189.1, Design of High-Performance Green Buildings, is the only consensus standard for high performance buildings, but questions exist as to whether or not it is consistent with high performance IAQ. This paper discusses high performance IAQ and how Standard 189.1 as well as other programs might move to higher performance IAQ.

In this study, the low-cost particle sensors were exposed to the indoor air and the results were compared with the advanced particulate counting technology, an optical particle counter (OPC), a scanning mobility particle sizer (SMPS) and an aerodynamic particle sizer (APS). Since the sensors work with light scattering, it was found that their outputs were affected with the ambient lights levels causing uncertainties in the measured results. Our research also indicates that the sensors are sensitive to 1μm size particles or greater, and their outputs are very sensitive to air circulation which make it difficult to compare with different technologies.

The wood floorings are perceived as natural and healthy materials. They are, however, a potential source of indoor VOC’s, which may worse the IAQ and human health. A new generation of biocompatible wood floorings has been tested for the VOC’s emissions and related health impact, together with floorings without evident low-emission attitude. The emissions have been measured using SPME GS-MS technique. The health impact has been classified using chemical and medical databases. Biocompatible floorings emissions resulted in naturally occurring terpenes, showing no evident treat to human health. Other flooring’s emissions are compared with an analysis of potential hazards.

With the increase in Legionella outbreaks in the past year, the industry has placed greater attention on the maintenance of building water systems, even establishing minimum legionellosis risk management requirements through ASHRAE Standard 188-2015. Director of Liquid Solutions at Goodway Technologies Ray Field, BChE. will speak to how Legionella develops, is transmitted, and how it can be managed through a five-step preventative maintenance program. He will explain how proper maintenance not only reduces the risk of a Legionella outbreak, but leads to better indoor air quality, lower operational costs and longer industrial equipment life.

There are no consensus criteria or standard evaluation procedures for this parameter. General principles for the establishment of building dampness criteria are discussed and a comprehensive dampness protocol is proposed. Assessment is based on review of site history, visual inspection and moisture measurements.

ASHRAE Standards addressing VOC mixtures were developed with considerable scientific uncertainty. The IAQ Procedure is being used to lower ventilation rates based on assumptions that Contaminants of Concern (COC) can be used as surrogates for overall IAQ and that concentration limits suggested by “Cognizant Authorities” can be used to determine if IAQ is acceptable. Standard 189.1 specifies a list of 32 VOCs for pre-occupancy sampling, with high performance credits awarded when measured concentrations are below State of California target values. This review examines assumptions underlying Standards 62.1 and 189.1 in view of recent studies and field experience. The authors propose that ASHRAE organize a Multi-Disciplinary Task Group to review issues associated with VOC mixtures and make recommendations to update current standards.

The National Institute for Occupational Safety and Health (NIOSH) Health Hazard Evaluation (HHE) program completed evaluations of water damage and mold contamination at three schools. We looked at employee symptoms, workplace conditions, and the effects of remediation on the work environment. We evaluated the ventilation system renovations and the effect these changes had on fungal contamination. We used supplemental evaluation tools such as measuring allergens present in dust to aid in our understanding of damp environments and potential health effects. We identified areas in need of improvement at each facility and research areas to pursue in future investigations.