United States Air and Energy Engineering

Environmental Protection Research Laboratory

Agency Research Triangle Park, NC 27711

Douglas W. VanOsdell

E AP Project Summary

Ventilation Research:

A Review of Recent

Indoor Air Quality Literature

Research and Development EPA/600/SR-94/180 November 1994

The objective of this literature review

was to survey and summarize recent

and ongoing research into indoor air

quality (IAQ)-related ventilation topics.

This Project Summary was developed

by EPA’s Air and Energy Engineering

Research Laboratory, Research Triangle

Park, NC, to announce key findings of

the research project that is fully documented in a separate report of the same

title (see Project Report ordering information at back).

Purpose

This review was undertaken for two reasons:

1. to investigate and evaluate the possibilities, capabilities, and limitations

of ventilation and ventilation systems as a means to improve IAQ,

and

2. to recommend for consideration

those areas of ventilation research

that might prove helpful in solving

the IAQ problem in commercial and

other buildings.

General Description

The review showed that there are three

general types of IAQ research activities

currently under way:

1. basic laboratory investigations into

the characteristics of sources and

processes that influence IAQ,

2. applied engineering research into

transport, dispersion, control devices, control strategies, and costs,

and

3. surveys and evaluations of the energy/economic impact of IAQ and

communication of research results

to users.

The ventilation research encompassed

by the scope of this review largely falls in

the second category. This broad category

of IAQ applied engineering research is

reviewed within the following framework:

1. Pollutant Transport—from source to

building envelope boundary (dispersion/wind transport) to entry into

the envelope (heating, ventilation,

and air conditioning (HVAC), infiltration, and doors/windows),

2. Air Cleaner Research—in-duct air

cleaners, in-room air cleaners, and

radon control by particle capture,

3. Diffuser Research—room airflow

and pollutant dispersion, fundamental source/sink transport, and jet/

diffuser flow,

4. Single-Room Flow and Dispersion—

single rooms and macromodels,

5. Building HVAC Flow and Dispersion—multizone buildings and

macromodels, schools, hospitals,

and other special buildings,

6. HVAC/Building Design, Operation,

and Control—HVAC system design

and selection, innovative ventilation

delivery designs such as ventilated

workstations, personally controlled

ventilation systems, displacement

ventilation, demand-controlled ven-
2

tilation, and energy recovery systems,

7. Applied Biocontaminant Research—

principles of microbiological reduction and control,

8. Building Performance—evaluation

and measurement of air exchange

rate, ventilation effectiveness, and

interzonal transfers.

The review included appropriate literature citations for the past 5 years. It also

captured current information from research

programs from the American Society of

Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), the Department

of Energy (DOE), and the National Institute of Standards and Technology (NIST).

Review Findings and

Reccommendations

The review led to the following research

recommendations:

1. Pollutant Transport—there are

many important areas of concern in

the pollutant transport research

topic; however,the area of building

infiltration seems to be understudied.

The need arises from the fact that infiltration air can become contaminated by

building materials or by materials of microbiological origin. Little research has

been conducted in this area.

Another area of concern is the effect of

wind pressure fields on building ventilation in general and outdoor air exchange

rates.

2. Air Cleaner Research—the performance of air cleaners should be

evaluated with tests that provide

HVAC system designers the

needed information to specify air

cleaners and reliably predict their

performance.

Standard air cleaner test methods for

both particle and gas-phase contaminants

need to be developed.

3. Diffuser Research—development of

improved models of diffuser flow

(particularly for cold-air distribution

systems) and the impact of diffuser

design on ventilation effectiveness

is a very useful research topic.

4. Single-Room Flow and Dispersion—

a primary knowledge gap that exists appears to be experimental

measurements that can be used to

evaluate the many available computational flow dynamics (CFD)

models.

5. Building HVAC Flow and Dispersion—the most important need appears to be improved measurement

techniques, including the development of standardized methods.

Development of such methods

would encourage their use, ensure

a supply of consistent data for

model development, and increase

the overall amount of performance

data available. These data could

be used to validate and improve

CFD computer models.

6. HVAC/Building Design, Operation,

and Control—an important need appears to be in gathering and organizing what is known about designing buildings and choosing HVAC

systems to ensure good IAQ.

This information would then be communicated to the building industry. A good

approach would be to use a cost and

energy modeling simulation program to

determine the best energy/cost/IAQ design for HVAC systems used in different

types of buildings located in various climates and with varying space usage.

A systematic investigation of the performance, costs, and benefits (including energy impact) of standard and innovative

ventilation schemes would allow designers to make early use of these technologies if they prove worthy.

7. Applied Biocontamination Research—there are two areas of concern with this topic: strengthened

HVAC maintenance practices, need

to be strengthened, possibly

through education or maintenance

standards, and basic research into

the conditions and materials that

affect microbial growth in HVAC

systems.

8. Building Performance—as with the

air distribution category, the primary

research needs for building performance evaluation are for improved

sensors and measurement techniques, and a standardized evaluation protocol.
3

D.W. VanOsdell is with Research Triangle Institute, P.O. Box 12194, Research

Triangle Park, NC 27709-2194.

Russell N. Kulp is the EPA Project Officer (see below).

The complete report, entitled “Ventilation Research: A Review of Recent Indoor Air

Quality Literature,” (Order No. PB95-129086/AS; Cost: $19.50; subject to

change) will be available only from:

National Technical Information Service

5285 Port Royal Road

Springfield, VA 22161

Telephone: 703-487-4650

The EPA Project Officer can be contacted at:

Air and Energy Engineering Research Laboratory

U.S. Environmental Protection Agency

Research Triangle Park, NC 27711

• •

United States

Environmental Protection Agency

Center for Environmental Research Information

Cincinnati, OH 45268

EPA/600/SR-94/180

Official Business

Penalty for Private Use $300

BULK RATE

POSTAGE & FEES PAID

EPA

PERMIT No. G-35