Reference NBS

PUBLICATIONS

AlllDb 3 1 fl b 3

NBSIR 86-3305 j

Rationale and Plan for Center for

Building Technology Research to

Improve Indoor Air Quality

P. E. McNall

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Gaithersburg, MD 20899

January 1 986

“ ~ DEPARTMENT OF COMMERCE

Q C

NAL BUREAU OF STANDARDS

100

• U56

86-3305

1986

L J

RATIONALE AND PLAN FOR CENTER FOR

BUILDING TECHNOLOGY RESEARCH TO

IMPROVE INDOOR AIR QUALITY

NBS EE3E/RCW rirrORMATION

- Ai gS

a ir\r\ lx L> ( U U

no,

P. E. McNall

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Gaithersburg, MD 20899

January 1986

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS. Ernest Ambler. Director
J

•
ABSTRACT

This report outlines a suggested five year research plan for the Center

for Building Technology (CBT) in support of resolving the emerging indoor

air quality problem. The problem is defined, and the past research is

summarized. The important Federal responsibilities are identified. NBS

contributions and capabilities are noted. Future research needs are

covered, and these form the basis for the CBT research plan, in cooperation

with other Federal agencies, state and local governments and the private

sector.

Key Words: Chemical measurements, engineering, indoor air quality,

models, physical measurements., research plan.

1
Table of Contents , Page No.

Purpose 1

Importance of Indoor Air Quality 1

Federal Responsibilities in Indoor Air Quality 3

Non-Federal Activities 6

General Technical Issues and Background 6

Standards and Guidelines 10

Control Methods 12

Research Status of Some Pollutants 15

Comprehensive Indoor Air Quality Research Strategy of the

Interagency Committee on Indoor Air Quality (CIAQ) 30

- Major Tasks 31

- Current Federal Research on Major Tasks 32

- Future Research Needs of the Major Tasks . ... 41

NBS Competencies in Indoor Air Quality Research 45

Suggested NBS Role 46

Recent CBT Research on Indoor Air Quality 47

Outside Funding Possibilities for FY86 48

Expected CBT Research in FY86 49

CBT Research Plan 49

References 54

Appendix A - FY84 Project Summaries 57

Appendix B - FY85 Project Summaries 64

Appendix C - Projects Expected to be Funded in FY86 68

Appendix D - Unfunded Proposals Showing CBT Capabilities .. 74

ii
PURPOSE

The purpose of this report is to suggest a five year Center for Building

Technology, (CBT) research plan as part of the important national research

effort to improve indoor air quality (IAQ). Brief summaries are included

covering the importance of the issue, and the responsibilities of several

other Federal agencies in the area. The research status is reviewed,

focusing on areas in which further research is indicated. The National

Bureau of Standards, (NBS) technologies are covered emphasizing those

appropriate to the NBS mission in the broad area of indoor air quality. A

suggested CBT research plan, in cooperation with other NBS units, is then

presented

.

IMPORTANCE OF INDOOR AIR QUALITY

Much attention has been accorded to outdoor air pollution in the past,

primarily an Environmental Protection Agency (EPA) responsibility. In

addition, the National Institute for Occupational Safety and Health (NIOSH)

and the Occupational Safety and Health Administration (OSHA) have had

significant effects on the air quality of the work environment, primarily

in industrial situations. Less attention was paid to residential and

commercial indoor air quality. However, surveys shows that 80-90% of the

average person's time is spent indoors and a large fraction of that is

spent in residential or commercial environments (1). The quality of these

environments warrants more attention. In recent years a number of problems

have arisen and research has been accelerated. Legionnaires disease, "sick

building" syndrome, radon in buildings, formaldehyde from Urea Formaldehyde

Foam Insulation (UFFI), chipboard, etc., are only a few of the problems.

Many recent studies (2-5) have pointed out concerns about indoor air

quality in residences and commercial buildings. Concentrations of many

1
pollutants have been measured at levels which exceed standards set for

outdoor and industrial exposures. Energy conservation efforts, leading to

better sealed structures, increase the concentration of any internally

generated pollutant. This is especially true in new construction. Some new

materials and processes introduced into structures outgas pollutants, and

the increased use of unvented heating appliances tend to exacerbate

existing problems. Enough evidence has accumulated to raise serious

questions about the ability of our indoor environments to protect the

health and safety of occupants in many different situations.

Much is known about general control methods. Ventilation can be increased

at an increased energy and equipment cost, air treatment devices can be

used, pollutants can be controlled at the source or substitute materials

can be used. However, some possible solutions are often not economically

feasible. For example, it has been proposed to equip all residences with

air-to-air heat exchangers to increase ventilation rates, thereby

conserving energy and improving indoor air quality. These have been

estimated to cost $500-$l,000 installed (6). To apply them to the 80

million U.S. dwelling units would require a $40-$80 billion investment!

This is not a practical solution! While heat exchangers may be practical

cost-effective control means in some applications, it is presently

impossible to predict in which residences heat exchangers would be cost

effective. Each building is different in its indoor contaminants. To

predict the value of controls, we must know the current and projected

distribution of pollutants and their concentrations in a large sample of

different buildings. We must further know the short and long term health

effects of the pollutants on people. To do this peoples' temporal and

2
spatial exposure patterns must be known as well as the ep idemo 1 og ica 1

effects of pollutants. The efficacy and practicability of known and future

control strategies, (dilution, removal, exclusion, suppression, and

occupant actions) must be ascertained for the multitude of applications.

Only then can appropriate rational, technology-based policies and

recommendations be made. Until then, recommendations with incomplete data

must be employed to solve immediate real or suspected problems.

FEDERAL RESPONSIBILITIES IN INDOOR AIR QUALITY

At the current time, several Federal agencies share responsibility for

various aspects of indoor air quality. The Environmental Protection Agency

has five important mandates, 1. The Clean Air Act; 2. The Safe Drinking

Water Act; 3. The Federal Insecticide, Fungicide and Rodenticide Act; 4.

The Toxic Substance Control Act; and 5. The Uranium Mill Tailing Act.

Congress has established the Environmental Protection Agency as the lead

agency in coordinating further public-funded research on indoor air

quality

.

The Department of Health and Human Services, through the National Institute

for Occupational Safety and Health, the National Institute for

Environmental Health and Safety, the Public Health Service, and the Centers

for Disease Control have broad responsibilities for the public health, and

have long been involved in air quality studies, particularly in industrial

situations

.

The Department of Energy has a mandate to encourage safe energy

conservation measures in buildings and for appliances.

3
The Bonneville Power Administration and Tennessee Valley Authority, (part

of the Department of Energy), establish safeguards to protect public health

for customers in their service areas as part of their energy conservation

programs

.

The Consumer Product Safety Commission is charged with protecting consumers

from products which pose a threat to health and safety, such as unvented

combustion devices, building products and systems, and small appliances.

The Department of Housing and Urban Development must ensure that health

care facilities and homes covered by Federal mortgage guarantee programs

meet minimum standards for the protection of health and safety.

The General Services Administration, as builder and manager of Federal

buildings, establishes criteria for their design and performance.

The Department of Defense, the world's largest owner of buildings, is

responsible for providing healthful environments on DOD jobsites and base

hous ing

.

The Federal Trade Commission mandate is to protect the public from

misleading or false advertising.

The Department of Transportation establishes standards for public

terminals, including airports and bus stations.

The Department of Labor's Occupational Safety and Health Administration

sets standards for air pollutants at industrial and some commercial job

sites

.

4
The Nuclear Regulatory Commission issues standards for technology-based

ionizing radiation exposures.

In addition, the Department of Education is concerned with school health

and the Federal Aviation Authority is involved in air quality in aircraft

cabins. There are other agencies such as the U.S. Department of

Agriculture and the Veterans Administration which also have roles.

The Federal Interagency Committee on Indoor Air Quality (CIAQ) was formed

in 1979 to coordinate Federal research among the interested agencies,

including CBT. In 1983 the committee was reorganized by congressional

mandate. Four co-chairs were appointed. The EPA representative, Don

Ehreth, is chairman, with representatives from DoE, HHS and CPSC as cochairs. Sixteen Federal agencies including NBS (and CBT) are represented.

Since 1983, the Interagency Committee on Indoor Air Quality has been very

active. It organized several working groups concerned with:

Radon

Formaldehyde

Organic Chemicals

Combustion Sources

Pathogens and Allergens

Structure Characteristics

Field Studies

These groups first identified the state of research in their areas, and the

organizations and laboratories which were performing significant research.

Then each group drafted a suggested research strategy. The co-chairs

organized a coordinated document, a "Comprehensive Indoor Air Quality

Research Strategy" (7). After rev iew by the entire committee, it was

submitted to OMB, which approved it in March 1985. It was then submitted

to Congress. This strategy is summarized later and is the primary basis

5
for the CBT research recommendations.

NON-FEDERAL ACTIVITIES

Research is done by many in the non-Federal community. Much work is of a

proprietary nature and not easily available. Other work is done by

universities, the national laboratories, etc., with much funding from

government sources. Mentioned here are a few organizations which are

active, but this section cannot cover all the important contributions.

Only entities thought to be useful for future contacts and research

planning are mentioned.

Professional Societies and Associations - the American Society of Heating,

Refrigerating and Air-Conditioning Engineers, (ASHRAE) has a research

program in IAQ and writes voluntary standards. The American Society for

Testing Materials, (ASTM) writes voluntary standards. The Air Pollution

Control Association, (APCA) is concerned. The American Hospital

Association, (AHA) is active in the area.

Industrial Research Groups - The Electric Power Research Institute, (EPRI)

and the Gas Research Institute, (GRI) are actively sponsoring IAQ work.

Battelle and A.D. Little also have work underway, as well as others.

State and local governments, and energy utilities also have contributed.

GENERAL TECHNICAL ISSUES AND BACKGROUND

The many contaminants in the indoor air can be divided into particulates

(solids or liquid droplets) and gases or vapors. Within these types, there

6
are constituents which are known to be annoying and which are, or are

suspected of being, damaging to health. Others may be identified in the

future. Constituents which are annoying may impair human performance

without being deleterious to health. ASHRAE Standard 62-1981, "Ventilation

for Acceptable Indoor Air Quality" (8), defines acceptable air qua lity as

"air in which there are no known contaminants at harmful concentrations and

with which a substantial majority of the people exposed do not express

dissatisfaction." This recognizes both the health and comfort requirements

of acceptable air quality.

Some known important contaminants are discussed below:

Particulates - Standards often specify a limit of the mass concentration of

particulates expressed as micrograms per cubic meter (yg/m3) (9). These

include all particle sizes, or total suspended particulate concentration

(TSP). Larger sizes may constitute annoyance more than health problems.

For health, respirable suspended particulates (RSP) are important, because

such particles can lodge in the lung. Large particles lodge in the nasal

passages and are handled ordinarily by the person unless they are, or

contain, allergens or pathogens. Respirable particles are in the size

range up to 10 micrometers (ym).

Particulates of specific interest include:

1. Respirable particulates as a group

2. Tobacco smoke (solid and liquid droplets) (tobacco smoke also contains

many vapors and gases)

3. Asbestos fibers

4. Allergens (pollen, mold spores, insect feces and parts)

7
5. Pathogens (bacteria and viruses), almost always contained in or on

other particulates

6. Radon progeny (radioactive decay products of radon gas,

radioactive decay product of radium, which is ubiquitous in

crust )

.

Vapors and gases of particular interest include:

1 . Carbon monoxide

2. Radon (decay products become attached to solids)

3. Formaldehyde and other aldehydes (require special attention as

organics

)

4. Other volatile organic compounds (VOC) (several hundred have been

identified in tobacco smoke vapors alone)

5. Oxides of nitrogen

6. Chlorinated compounds (pesticides and solvents)

7. Carbon dioxide

8. Sulfur dioxide

Some contaminants enter with the outside air brought in by purposeful

ventilation or by uncontrolled infiltration. In the U.S., the EPA has

established outdoor pollutant criteria (9) and the public interest in

outdoor pollution has resulted in considerable action to improve it.

Currently, except for some local areas, the outdoor air quality is not

considered a significant health or comfort threat. Many of the

contaminants found in the air outdoors do not occur in high enough

concentrations to cause concerns, but have recently been recognized as

indoor health concerns. Examples are nitrogen oxides, carbon monoxide and

formaldehyde. However, most important indoor pollutants emanate from

inside sources or are concentrated there. People are sources of CO2 , and

the first

the earth's

8
biomatter, as well as other particulates and vapors whiclj are characterized

as "body odors." People's activities, smoking, cleaning, hobby activities,

such as gluing plastic models and refinishing furniture, cooking, etc.,

also cause pollution. Building materials and finishes can "outgas"

pollutants. Furnishings, business machines and appliances, particularly

unvented or poorly vented heaters and ranges, can be sources. The building

surroundings can be a source of radon and insecticides which enter the

indoors through cracks, drains, etc., or by diffusion. Heating,

ventilation, and air-conditioning (HVAC) systems, drains, plumbing systems,

and poor construction, housekeeping, and maintenance can result in

"environmental niches" where pathogens or allergenic organisms can collect

and multiply to be reintroduced into the air (10).

Similarly, there are many mechanisms which remove contaminants from the

indoor air. General and local exhaust systems are important, as is the

uncontrolled exfiltration of inside air. Particulates also settle on

horizontal surfaces due to gravitational forces and are precipitated on all

surfaces by electrostatic forces, diffusion and air motion.

Vapors and gases can be absorbed or adsorbed on materials of many kinds,

and can react with other airborne pollutants and be changed in character.

All of the above mechanisms occur continuously at generally uncontrolled

rates

.

Air cleaners can be used to remove contaminants. Particulate removal

techniques are well developed (11-12). Gaseous removal is less so, with

activated charcoal and potassium permanganate being most highly developed

( 12 ).

9
An additional complicating factor in contaminant concentration is the nonuniform mixing which is often present in buildings. Concentrations vary

spatially as well as temporarily. Pollutants may emanate from point

sources, such as an unvented space heater, or area sources, such as wall

panels, which adds further non-uniformity to the concentration.

Figure 1 shows graphically the general indoor air pollution situation,

including many of the mechanisms of the entrance, removal, and circulation

of pollutants.

The complexity of the problem requires careful research planning, employing

experts representing many technologies. Otherwise, data collected will

have limited utility for providing a useful data base for the development

of generally applicable and economic methods for improving indoor air

quality and for developing national policies.

STANDARDS AND GUIDELINES

The EPA has been active for years in setting standards for outdoor air (9).

HHS (NIOSH) (13-14) recommends standards for industrial workplace

environments. OSHA (15) issues workplace standards promulgating NIOSH

recommendations. The American Conference of Governmental Industrial

Hygienists (ACGIH) (16) has, as a professional society, issued workplace

standards, as has the American Industrial Hygiene Association (AIHA) (17).

These agencies have concentrated on the outdoor air and the industrial

workplace environments. While these standards for some particular

pollutants may be useful for other indoor environments, those nonindustrial environments are not specifically covered. A majority of people

spend most of their time living, working and visiting residential and

10
Outdoor

air

©

LL

cr; 3

ca JCX

\

E

QJ ~j

03 UZ

•uC

toe

-*E

cc

4-1 c

o

1

1

Contaminant

removal

Contaminant

introduction
commercial environments, therefore the need for better standards for these

environments is evident.

Since 1946, ASHRAE has been the only professional society producing

voluntary standards (with the American Standards Association, which is now

the American National Standards Institute [ANSI]) specifically designed for

the general population which occupies residential, institutional and

commercial environments. Its latest standard on this subject is

"Ventilation for Acceptable Air Quality," ASHRAE Standard 62-1981 (8).

This, and the earlier Standard 62-73, are the basis for most building codes

on ventilation. These standards are based upon research, past practices

and professional judgment. ASHRAE recognizes the developing state of

research, and is now revising the standard.

Recently, widespread indoor concerns with specific pollutant concentrations

have led to government indoor regulations on ozone (FDA) (18), asbestos

(EPA) (19) and OSHA (15), and formaldehyde (HUD) (20). Others are being

contemplated.

Considerable additional attention needs to be given to the development of

standards for general indoor environments.

CONTROL METHODS

Control methods are important means of mitigating indoor pollution

problems. As mentioned earlier, there are five basic methods for lowering

concentrations of indoor pollutants:

1. Ventilation is the most commonly used method for controlling indoor

12
pollution. Usually it is employed so as to dilute the indoor air with

quantities of outdoor air which are presumed to be less contaminated and

also to exhaust polluted air. In buildings with mechanical ventilating

systems, outdoor air quantities are provided by design, and the equipment

operated insofar as practical to bring in outside air at rates specified in

the applicable building codes. In these cases, near perfect internal

mixing is assumed. In other cases, local exhaust may be employed to

attempt to remove contamination near its source, such as in restroom

exhaust systems. In residences and other locations where mechanical

ventilation is not usually available, dilution is accomplished by natural

leakage through cracks, windows and other openings in the envelope. This

mechanism is highly variable, with wind, temperature differences and

structural qualities playing significant roles. Codes presume the leakages

to be adequate under ordinary conditions.

2. Removal of pollutants with special air treatment devices is employed

where specific problems exist, or are thought to exist, and practical

devices are available. Particulate filtering is a highly advanced

technology, but increased performance involves higher equipment costs.

Ordinary furnace filters are not effective in removing the respirable

suspended particulates (RSP), but are effective with pollen and other large

particles. High performance media filters and electronic filters are available at higher cost, and can remove from 80 to nearly 100% of the

respirable particles. However, with practical ventilation systems, even a

very efficient filter can only reduce indoor RSP levels to about 10-20% of

those which would exist using common furnace filters (21).

13
Vapor and gas removal equipment is also available, but the technology for

general use in ordinary occupied spaces is not well-advanced. Activated

charcoal filters are used to adsorb high molecular weight gaseous

molecules. It is difficult to determine when the filters are loaded,

except by odor response of the occupants. As the filters become loaded,

they also desorb the lighter molecules previously adsorbed, and this can be

a problem. Activated charcoal filters are widely available, in varying

efficiencies and holding capacities at costs in relation to their

performance

.

Potassium permanganate and other chemicals are available, impregnated into

porous alumina pellets. The chemicals can oxidize or otherwise change

some gases and vapors into other, less hazardous or odorous forms.

Other chemicals, used as "odor counteractants" have not been technically

proven to be effective.

3. Exclusion of offending materials from indoors is an obvious control

method. However, much work is necessary to identify all such materials and

to provide satisfactory substitutes. Such materials include paints and

other finishes, manufactured wood products, plastics, cleaning and

maintenance materials, etc. Also included are a multitude of manufacturing

processes that may be used to lessen the outgassing of some undesirable

materials

.

4. Encapsulation or coating materials, or otherwise interfering with the

materials' ability to off-gas pollutants is another control strategy.

14
5. The activities of building occupants is another control strategy. If

people are educated as to the effects of pollutants, they could act in ways

to mitigate their personal exposure. Opening windows and minimizing the

use of possible pollutants indoors are examples. This strategy relies on

eduction of many individuals, and may be difficult.

While it is seen that many control strategies are available, the costeffectiveness in practical applications is not well known, and much

research remains to be performed on the existing strategies, and to develop

new ones.

RESEARCH STATUS OF SOME POLLUTANTS

It is not possible to cover all the research done to date, but it is felt

useful to identify some of the important pollutants, and to briefly

summarize the research status of each. Each pollutant is described. Its

sources and, where not obvious, its entry into the indoor environment are

covered, as well as the geographical distribution and the general type of

structure in which it is important. Existing standards and guidelines

relevant to each pollutant are mentioned. The comfort and health effects

of the pollutants are categorized in three ways. The first is annoyance;

i.e., the pollutant can be perceived by occupants as not desirable. The

second is an acute effect resulting in symptoms of respiratory tract

dysfunction or other short-term disease. The third is a chronic or longterm effect, which may take decades to produce, such as lung cancer,

emphysema, and heart disease. The state of measuring instrumentation is

then covered. Current knowledge concerning mitigation techniques is

treated, followed by a summary of suggested future research.

15
Radon

Description - Radon is a radioactive gas, the first decay product of

Radium-226. It is an alpha particle emitter with a half-life of 3.6 days.

It decays further into solid alpha emitters which can become attached to

dust particles and surfaces in the environment and become lodged in the

lungs (22).

Sources - Radium is ubiquitous in the earth's crust in widely varying

concentrations. Well water and natural gas in some locations have high

concentrations of radon. In some specific cases (2) masonry building

blocks have high radium concentrations. The earth around buildings is the

principle source, and radon penetrates cracks and drain openings in

foundations, into basements and crawl spaces. Water containing radon will

outgas into spaces when drawn for use indoors. Some building materials

will outgas radon, some of which may enter buildings.

Location and Type of Structure - Geological studies have indicated

geographic areas of high radon concentration in soils and water (4), and

much attention has been given to these areas. It is not possible, however,

to predict which subgroup of structures will have problems, due to the many

other factors involved, such as the fill variations around buildings and

foundation tightness. Radon is associated primarily with low-rise

residential dwellings with concentrations generally being higher in

basements than in upper floors (22).

Standards and Guidelines - Several standards and guidelines exist.

16
Organization Radon level above which mitigating action is

indicated, picocuries per liter (pCi/L)

U.S. Mine Safety and

Health Administration (23) (for mines)

16

U.S. Bonneville Power

Administration (of DoE) (23)

5

EPA (23)

for residences

and commercial

buildings 4

ASHRAE Standard 62-1981 (8) 2

Comfort and Health Effects - No sensory perception or acute health

effects due to exposure to radon and radon daughters are known. The

chronic effect is suspected to be lung cancer or other lung dysfunction due

to retention in the lung of radon decay products. These chronic effects

are among the best known of all indoor pollutants, as the result of studies

on uranium miners for many years (24). The levels of radon are high

compared to most buildings. It is speculated that non-occupationa 1 radon

exposure in the U.S. may cause between 2,000 and 20,000 additional cancer

deaths per year, and that one million U.S. dwellings have concentrations

which may cause a significant risk to their occupants (7).

Measuring Instruments - Relatively inexpensive passive track-etch

detectors (less than $50) are available for survey use, integrating radon

concentration over a one- to three-month period. Air sampling instruments

for real-time measurements (scintillation counters for example) are more

expensive. No inexpensive method exists to measure radon daughter

concentrations

.

Mitigation Measures - Sealing of foundations to prevent entry has been

demonstrated to be effective (25). Specific ventilation of basement areas

17
and crawl spaces has also been shown to be effective (26). Increased

ventilation with outdoor air will lower radon levels for a given building.

However, radon levels do not correlate well with ventilation rates among

different buildings (3). This is because source strengths of soil radon

are quite variable. Therefore, increased ventilation cannot be relied upon

to lower radon levels enough in all buildings where it is a problem.

Important Areas for Future Research - Needed are predictive models to

assist in pinpointing problem structures; development of better costeffective mitigation methods, devices, and materials; better building

construction practices in radon-rich areas, as well as soil assessment

methods prior to construction; and also better standards to guide economic

mitigation measures.

Asbestos

Description - Asbestos is composed of small natural mineral silicate

fibers widely used in insulation and other building materials until

recently. The use of asbestos-containing spray-on materials is banned in

U.S. buildings today (27).

Standards and Guidelines - There is currently no known "safe"

concentration. The Occupational Safety and Health Administration (OSHA) is

using a level is 0.1 fibers longer than 5 urn per cubic centimeter (f/cm3)

as the level above which abatement action must be taken (15). Currently

there is discussion as to whether a level of 0.01 f/cm3 may be more

appropriate

.

Comfort and Health Effects - No acute health or comfort effects are

18
known. Fibers deposited in the lung are the only known cause of

mesothelioma, a fatal cancer of the pleural or peritoneal area of the lung.

Asbestosis and other lung conditions also have been identified (28).

Extensive studies with asbestos workers have established the seriousness of

these chronic problems (28).

Measuring Instrument - Phase contrast microscopy (PCM) is used as a

screening method for sampling asbestos fibers in the air (15). A sample is

collected on a membrane filter. Part of the filter is treated chemically

to render it transparent. Particles are observed for shape and size, and

the results are presented as f/cmJ of 5ym or longer. Fibers other than

asbestos (e.g., glass, cellulose) are also counted (29). Electron

microscopy is a method which can distinguish asbestos definitively, but it

is much more expensive than PCM (29).

Mitigation Measures - Asbestos abatement in the U.S. is being handled

as a special case separately from other air pollutants by U.S. agencies due

to the perceived high public risk (15) (27). Reference 29 gives a more

complete discussion of asbestos in buildings and suggested abatement

guidelines. References 15 and 29 contain some regulations.

Areas of Future Research - Due to the time-varying nature of fiber

release into the air caused by a number of activities in buildings, a better method of assessing the exposure of occupants is needed. Further

determination of health effects of low exposure levels is needed.

Measurement and abatement methods, which are now very expensive, need

improvement

.

19
Tobacco Smoke

Description - Tobacco smoke consists of solid particles, liquid

droplets, and gases resulting from tobacco combustion. Particles of

condensed combustion products are almost all in the respirable range, and

over 2,000 specific materials have been identified in the particulates and

associated gases (30).

Standards and Guidelines - No general levels have been agreed upon.

ASHRAE Standard 62-1981 (8) specifies dilution with smoke-free air in

quantities of 7-17.5 liters per second (L/s) per person, where smoking is

permitted, depending upon the type of space. The standard is currently

being revised but no significant change in these levels is now

contemplated (30).

Comfort and Health Effect - Many people who do not smoke object to

smoke in their environments as an annoyance (30). Tobacco smoke's health

effect on nonsmokers (passive smoking) has had increased research attention

recently (30). Its effects on smokers are well known. Acute health

effects have been found in the lung function of children and spouses of

smokers (31). Allergic reactions occur in a small fraction of the

population. Some studies suggest that the chronic lung cancer risk of

nonsmokers exposed to significant levels of smoke may be twice that of

people who are not exposed to significant passive smoking (32).

Measuring Instruments - Particulate concentration is measured

gravimetrica 1 ly or by optical scattering of particles collected on filters.

Gas chromatographs are used for gases. Enough work has been done so that

reasonable estimates of the source strength can be made by simply counting

20
smokers and knowing that about 30% of adults each smoke about two

cigarettes per hour while awake (2).

Mitigation Measures - Prohibition of smoking in public spaces is

becoming more common. Isolation of smokers is partially effective, but it

usually also requires careful management of ventilation to be most

effective (28). High efficiency air cleaners and gas filters are sometimes

effective, if well applied and properly maintained. Increased ventilation

is partially effective, but dilution in general spaces is often not totally

effective, since very large ventilation rates are necessary to dilute smoke

enough to be unobjectionable to most nonsmokers (4).

Areas of Future Research - Better quantification of health effects on

nonsmokers; and development of more economical filter systems and

ventilation strategies.

Formaldehyde

Description - Formaldehyde (HCHO) is a colorless water-soluble gas,

which, due to its wide use and possible health effects, is such an

important volatile organic compound (VOC) that it is considered searately.

Sources - Materials containing formaldehyde are widely used in

buildings, furnishings, and consumer products. Urea-formaldehyde resins

are used in the manufacture of plywoods, particleboards, and textiles.

Some buildings have been insulated in the side walls with urea-formaldehyde

foam insulation (UFFI). This product is banned in Canada and

Massachusetts; unsuccessful attempts were made to ban it throughout the

21
U.S., but the resulting publicity has effectively closed that market. In

the U.S., however, as many as 500,000 homes have been insulated with UFFI

(14). Formaldehyde outgases from the above-mentioned products and has been

a serious problem in many residences. Mobile homes have been particularly

affected because of their small volume and the large amounts of

formaldehyde-containing products found in them. Tobacco smoke and other

combustion products are lesser sources. Indications are that time

diminishes the outgassing from materials, so concentrations in spaces

diminish with time. However, several years may be necessary to alleviate

some problems.

Standards and Guidelines - There is much controversy concerning

appropriate maximum levels for human occupancy. Scandinavian countries

have established 0.1 ppm as a limit. ASHRAE has also included 0.1 ppm in

its Standard 62-1981 (8), but the formaldehyde provision has yet to be made

mandatory in building codes because of the controversy concerning possible

health effects at these low levels. Some states in the U.S. have

established 0.4 ppm in their codes for residences. In the U.S., the

Department of Housing and Urban Development has developed a product

standard for emission rates of plywood and other wood materials for

manufactured housing (20).

Comfort and Health Effects

detected by many people at le

annoyance, it also causes acute

and the respiratory tract (14).

in laboratory animals, but the

for human beings (7). A number

- Formaldehyde has a pungent odor and is

vels of about 0.1 ppm (31). Besides the

eye burning and irritates mucous membranes

Formaldehyde has also caused nasal cancer

chronic effects have not been established

of people exhibit a high sensitivity to

22
very small concentrations (14).

)

Measuring Instruments - Inexpensive passive samplers have been

developed but their accuracies are not well established (3). Formaldehyde

is extracted in a laboratory from a solid adsorbent in the passive samplers

by water and the amount measured. The more traditional method of

collecting formaldehyde is by impingers. Formaldehyde concentrations are

usually determined by the pararosani 1 ine or chromotropic acid methods. A

third, the acety lacetone method, is less common (3).

Mitigation Measures - For problem UFFI cases, removal is indicated.

The cost can be as high as $20,000 for a residence. Even then, residual

materials may remain in the structure and continue to outgas. Increased

temperature, humidity, and ventilation will accelerate outgassing. Some

manufacturers are producing products with lower outgassing rates. Some

surface treatments are being used to seal against outgassing, but these are

still being studied.

Areas of Further Research - Both the measurement methods for

formaldehyde and the calibration of these methods needs research. Product

standards to limit outgassing need further development and application.

More practical remedial measures for use in existing buildings are needed.

Better material outgassing characteristics and models are needed.

Nitrogen Oxides

Description - The two most prevelant oxides of nitrogen are nitrogen

dioxide (NO 2 ) and nitric oxide (NO). Both are toxic gases with NO 2 being a

highly reactive oxidant, and corrosive. The NO gradually reacts with the

23
oxygen in the air to form NO2

.

Sources - The primary sources indoors are combustion processes, such

as unvented gas ranges, other unvented heaters, and tobacco smoke.

Unvented heaters are experiencing increasing residential use in the U.S.

due to their perceived energy-saving potential.

Standards and Guidelines - None have been agreed upon for indoor air.

The U.S. National Ambient Air Quality Standards lists 100 pg/m^ as the

long-term (8 hr) limit (9).

Comfort and Health Effects - Oxides of nitrogen have no sensory effect

in low concentrations. Acute effects of lung dysfunction have been

reported at higher concentrations. Chronic effects are not well

established

.

Instrumentation — Small passive NO

2 monitors suitable for field use

are available (3).

Mitigation Measures - Venting the NO2 source to the outdoors is the

most practical measure for existing conditions. Limited exposure to

sources through behavior modification could be of some benefit to health.

Manufacturers are developing devices having lower NO 2 generation.

Area of Future Research - Better methods of predicting where problems

exist and the development of more practical mitigation measures are needed.
Other Volatile Organic Compounds (VOC)

) Description - There are hundreds of other volatile organic compounds

that are found in the indoor air,

suspected of being harmful. Those

complete list.

Compounds

acetone

alcohols

acids

aromatic hydrocarbons

chlorinated hydrocarbons

organophosphates

chlorinated compounds

acetone

ammonia

toluene

benzene

sometimes in concentrations which are

listed below are examples, but are not a

Sources

effluents from peoples'

metabolism

various combustion processes

pesticides

building materials

personal care products,

cleaners, paints, etc.

Measuring Instruments - Gas chromatographs are used for laboratory and

some field studies. No inexpensive monitors suitable for extensive field

use exist, but adsorbers can be used for later laboratory analysis.

Standards and Guidelines - None have been set for non-industrial

indoor air. NIOSH (13) has recommended occupational standards for many

compounds. ASHRAE Standard 62-1981 (8) includes a rationale suggesting

that in the absence of better data, the NIOSH limits be divided by 10, to

account for the possible continuous, rather than workplace, time of

exposure and, to account for the elderly, young and infirm in the general

population compared to the generally healthy working population.

Comfort and Health Effects - Several of these compounds have been

identified individually as causing acute and chronic effects at high

concentrations (13). Some cause cancer. The effects of combinations of

25
these compounds at low concentrations have been suggested as causes of

) several "sick building" situations (2).

Location and Type of Structure - These are widely distributed in all

building types.

Mitigation Measures - Where practical, uses of these sources should be

restricted and these materials should be stored in well ventilated areas

apart from occupied zones.

Areas of Future Research - Determination of the health effects of

combinations of VOCs at low concentrations found in buildings is a need.

Inexpensive sensors would also be useful. Practical removal hardware and

other control devices are needed. Studies of substitute material

compositions for lower emissions are needed.

Carbon Monoxide

Description - CO is a colorless, odorless, and tasteless gas. It

results from incomplete combustion of carbon in fuels and is almost always

accompanied by N0

x

.

Sources - Any incomplete combustion which might arise from gas ranges,

unvented heaters, leaky wood and coal stoves, and tobacco smoke may cause

high concentrations in inside air. Only worn or poorly adjusted and

maintained combustion devices seem to be significant sources. Automobile

exhaust may enter houses from attached garages or enter buildings built

over garages or near busy trafficways.

26
Standards and Guidelines - The U.S. National Ambient Air Quality

L

Standards lists 40 mg/nr as the one-hour limit (9).

Comfort and Health Effects - Acute affects are due to the formation of

carboxyhemog 1 ob in in the blood, inhibiting oxygen intake. In moderate

concentrations, cardiovascular disease, impaired vision, and loss of brain

function may results. At higher concentrations it is fatal (4). CO is a

serious problem in dwellings in developing countries due to extensive use

of unvented combustion sources for heating and cooking.

Instruments - Some relatively high-cost infrared-radiation absorption

instruments exist. Some moderately priced ($50) small real-time measuring

devices are also available.

Mitigation Measures - It is most important to be sure appliances are

clean and properly adjusted. Automobiles should not be run for extended

period in attached garages. Additional ventilation can be used as a

temporary measure when high levels of CO are expected for short periods of

time.

Areas for Further Research - CO and its perils have been well known

for a long time and public awareness is high. A low-cost alarm system is

needed which could save some of the CO-re lated deaths.

Carbon Dioxide

Description - CO 2 is an odorless, tasteless, and colorless product of

completed carbon combustion.

27
Sources - All combustion processes and metabolic processes are CO 2

) sources .

Location and Type of Structure - In buildings, higher CO 2 concentrations are primarily associated with residences since unvented

combustion is not usually permitted in other buildings. Low concentrations

of CO2 from people and smoking are always present in all buildings.

Standards and Guidelines - NASA maintains CC>2 levels of 1% or less for

space environments, and U.S. submarines operate at 0.7% or less, indicating

that young people in good health can perform without hazard at these

levels. World Health Organization (WHO) guidelines (33) are 0.5% for

indoor air and ASHRAE Standard 62-1981 (8) sets 0.25% as the upper limit.

The outdoor level is usually 0.03%. Indoor concentrations are usually in

the range of 0.1%.

Comfort and Health Effects - At concentrations above 1% in air, some

loss of mental acuity has been noted. No major comfort or health effects

in buildings have been noted because measured building levels are well

below 1%.

Measuring Instruments - Instruments exist which are reliable and

inexpensive enough for some commercial ventilation applications.

Area for Further Research — CO 2 has been proposed as an indicator of

general air pollution problems and body odors when human occupancy is the

major cause of pollution. But as is seen in this report, many other

important pollutants which are not related to human occupancy can often be

28
present. CO 2 control has also been tested experimentally as a "peoplecounter" in buildings to control ventilation proportional to the occupancy

as an energy-saving strategy. Lower cost sensors and more field

demonstration are needed.

Microorganism And Allergens

Description - Biological material, bacteria, viruses, mold spores,

pollens, insect parts and feces, house dust mites, etc. are ubiquitous in

indoor environments. These particulates range from less than one to

several m in size. When airborne, they are usually attached to dust

particles of various sizes so that all sizes of airborne particulates may

include them.

Sources - People and pets "shed" such materials. Indoors, bedding,

carpeting, and other places where dust collects can harbor them. Cooling

towers have been known to be incubators of Legionella. Dirty airconditioning equipment, humidifiers, condensate drains, and ductwork can

incubate bacteria and molds (2). High humidity areas exacerbate their

growth.

Standards and Guidelines - No standards for general

applications exist. Cooling tower treatment procedures

the levels of Legionnella and other organisms do exist (34).

Comfort and Health Effects - Tuberculosis, measles, small pox,

staphylococcus infections and influenza are known to be transmitted by air

as is Legionnaires disease (28). Upper respiratory disease, causing each

person an average of about four days restricted activity per year, is a

indoor air

to reduce

29
large economic cost associated with airborne transmission of disease (28).

"Indoor airborne viruses and bacteria are the most important cause of acute

disabling illnesses in the U.S." according to Hinkle (35). Pollens, molds,

etc., cause allergic reactions for a significant portion of the population.

Measuring Instruments - Air samples can be collected on filters or

impactors and incubated for visual examination of viable growths.

Microscopic examinations of collected dust can be used to identify molds

and pollen. No inexpensive field monitors exist which are suitable for

large-scale use. Coated microscope slides and Petri dishes, which collect

settled particles for laboratory analysis, have limited utility in surveys.

Mitigation Measures - General good housekeeping and maintenance of

heating and air-conditioning equipment are important. Adequate ventilation

and good air distribution also helps. High-efficiency air cleaners remove

viable particles along with other particulates.

Areas for Further Research - The relationship of concentration of

pathogens in the air to disease transmission is not well established. More

economical air-treatment devices are needed, as well as better

understanding of the roles of housekeeping and air-conditioning system

maintenance

.

COMPREHENSIVE INDOOR AIR QUALITY RESEARCH STRATEGY (7)

This report (7), mentioned earlier, describing a government-wide research

strategy, is now summarized since it is the current coordinated proposal of

future needed Federal research. It also includes suggested research

contributions from state and local governments and the private sector.

30
The strategy aims at two objectives.

1. To develop an understanding of the magnitude of the risk to human

health from exposures to indoor air pollutants, and the contribution

of various energy conservation measures, introduction of new building

materials and consumer products.

2. To provide technical information and guidance, including costeffective mitigation measures, to state and local governments, the

private sector and the general public.

Major Tasks

To accomplish these objectives, the following six tasks were identified as

critical elements of the strategy. These tasks form the basis of this

research strategy, and are interrelated. In addition, they are consistent

with the recommendations expressed by non-Federal groups, WHO, NAS, ASHRAE,

and others. Accomplishment of these tasks requires an integrated effort.

1. Identification of indoor air pollutant sources and factors affecting

human exposure.

2. Characterization of indoor air quality.

3. Determination of the relationship between energy conservation and

indoor air quality.

4. Determination of the health effects of indoor air pollution.

5. Determination of optimal control and mitigation techniques.

6. Development and conduct of national multipollutant field studies.

31
Current Federal Research on Major Tasks

Task #1: Identification of Indoor Air Pollutant Sources and Factors

Affecting Human Exposure

The identification of significant sources of indoor air pollutants (Table

1), their migration pathways and environmental factors that influence human

exposure provide the basis for the interpretation of monitoring data and

the development of cost-effective control technology. To date, a high

priority has been placed on the basic phenomena that affect human exposure

for radon, formaldehyde and other organics, and combustion pollutants.

Efforts to determine the sources and dynamics of indoor radon are directed

to

:

1. Determining the contributions of soil, water, and building materials

to the indoor radon source term;

2. Developing models that relate indoor radon concentrations to the

various sources, migration pathways, driving forces, and air

infiltration rates;

3. Determining environmental factors, such as building construction,

particulate concentrations, temperature, pressure, humidity, and human

activity patterns, that influence human exposure to radon and its

decay products; and

4. Determining the radiation dose to the respiratory tract from the

inhalation of radon decay products.

32
Sourc es

Table 1: Typical Sources of Indoor Air PollutantsPel lutant 3

Ambient Air Sulfur Dicxide (S02

), Nitrogen Oxides

(NCX

) , Ozone, Carbon Monoxide (CO),

Particulates, Organics, Metals

Soil Radon

Water Radon, Volatile Organics

Combustion Engines N0_, CO, C0 2 , Organics, Particulates,

Metals

3uilding Materials

Concrete, Stone, Brick

Pressed Wood products

Insulations

Adhesives, Paints and Solvents

Radon

Formaldehyde, Other Volatile Organics

Formaldehyde, Fibers , Asbestos * Volatile Organics

Air Conditioners, Humidifiers Bacteria, Fungi, Protozoa

Combustion Appliances

(gas, wood, coal, oil and

kerosene)

N0Z , CO, C0 2 , Water Vapor, Organics,

S02

, Particulates

Furnishings Formaldehyde, Other Volatile

Organics, Fibers

Office Machines and Supplies Organics, Particulates, Ozone

Cleaners and Polishes Ammonia, Volatile Organics,

Particulates

Hunan

Metabolic

Smoking

Cooking

Hobbies

Hygiene

C0 2 , Odors, Water Vapor, Bacteria

CO, C0 2 , N0 2

, Organics, Particulates

Organics, Odor, Water Vapor

Organics, Microorganisms

Organics, Odor

Animals and Pests Microorganisms, Mites, Allergens,

(animal dander, insect parts and

feces

)

Plants, Microbial Contamination Spores, Pollen, Allergens

Asbestos research is not discussed in this strategy, because Federal

research and regulatory action are coordinated through the Federal

Asbestos Task Force.

33
Research on organic pollutants is directed toward determining the

contribution of various building materials as chronic sources of airborne

pollutants, including formaldehyde. The relationship between pollutant

emissions from building materials and building-related factors such as

construction techniques, ventilation, temperature, humidity and age of the

material are being studied. Consumer products and structural sources of

various organic compounds identified indoors are also being evaluated.

Studies are in progress to determine the emission properties and major

pollutants of combustion sources such as unvented kerosene and gas heaters

and coal/wood stoves. The influences of appliance design, ventilation and

use patterns are included in this research.

Task #2: Characterization of Indoor Air Quality

Earlier studies which characterized indoor air pollutants were limited in

scope because they used small sample sizes, measured only single or few

pollutants, studied a single source, were conducted in a limited geographic

area or used different methodologies. Though valuable in their context,

these data do not provide a unified national picture of indoor air

pollution. Therefore, a national multi-pollutant field survey would

provide the data base required to develop hypotheses and further test and

determine dose-response relationships. However, before conducting such a

study, there must be an effort to:

1. Develop instruments to monitor pollutants and gather other

relevant data;

2. Field test these instruments for efficacy, reliability, and

cost-effectiveness

;

3. Develop analytical tools and models; and

34
4 . Centralize this information where interested parties can

have access to it.

Current Federal research which supports these efforts is summarized below:

Methods Development - Research to develop passive samplers for

CO, NO 2 , CO2

, volatile organics, water vapor and air exchange rates is in

progress. Simple cost-effective active sampling techniques for CO, N02>

formaldehyde, and organic vapors are being evaluated.

Field Monitoring Studies - Both existing and new methodologies

are being tested for appropriateness and cost-effectiveness in pilot

studies .

Analytical Methods and Models - Mathematical models are being

developed to relate indoor pollutant concentrations to pollutant sources,

removal mechanisms, thermal comfort parameters, and air exchange rates.

These models will be used to predict indoor air quality and associated

health effects in indoor environments, to simulate the effects of proposed

mitigation efforts, and to perform cost-benefit analyses. The models will

be validated and verified by field data.

IAQ Data Base - To maximize analysis and distribution of

information to interested Federal and local agencies and the private

sector, uniform data formats are needed. Results from past field studies

are being compiled for entry into a single data base. Results from current

and future field studies will also be entered into this data base.

35
Task #3: Determination of the Relationship Between Energy

Conservation and Indoor Air Quality

Energy conservation and indoor air quality requirements will have important

ramifications on the cost, design and operation of comfort conditioning

systems, energy use patterns and peak energy usage.

The growing trend in new construction is substantially reduced

infiltration. For residences, typical levels of about 0. 7-1.0 air changes

per hour may be reduced to as low as 0.1 to 0.2 air changes per hour. When

infiltration is reduced to this extent, elevated levels of indoor

pollutants will be found. More research is required to relate ventilation

rates to indoor air pollutant concentrations and to provide for the

establishment of energy efficient ventilation guidelines which maintain

acceptable indoor air quality.

Infiltration and Ventilation - Research efforts devoted to

infiltration and ventilation studies in residential buildings have

contributed significantly to the development of infiltration measurement

techniques, air leakage characterization of buildings, and infiltration

models to assess the impact of reduced infiltration rates on energy

requirements and indoor air quality. Current research includes:

1. Extending single chamber, residential infiltration models to

include all forms of ventilation (both natural and

mechanical)

;

2. Developing and validating low cost methods of measuring

infiltration and leakage, (e.g., passive perf luorocarbon

tracer gases techniques and acoustic AC pressurization);

36
3 . Testing a multi-chamber infiltration model suitable for

) multi-family residential buildings and multizone singlefamily buildings; and

4. Participating in national and international efforts to

develop ventilation, leakage, infiltration, and construction

quality guidelines.

Only very limited information exists on infiltration and ventilation in

commercial and institutional buildings. Research is required to develop

and validate techniques to measure ventilation rates and air distribution

patterns. Prototype systems are being developed which utilize multiple

tracer gases, both actively and passively. Research efforts will test and

validate these systems. Data on ventilation rates and efficiencies are

being collected in a number of commercial buildings and will be used to

extend the multichamber infiltration models described above.

Combustion Appliances and Building Materials - Research on

supplemental heating appliances has included field studies, laboratory

chamber studies of pollutant emission rates, consumer use surveys and

limited exposure modeling. Current efforts concentrate on development of

certification test methods and voluntary guidelines for these appliances.

Formaldehyde emissions from urea-formaldehyde foam insulation, pressed wood

products and fibrous glass insulation have been characterized and

evaluated. This information has been provided to manufacturers and to

consumers for their consideration in development of voluntary guidelines.

In addition, volatile organic emissions from building materials, such as

37
sealants and caulking compounds, are now being investigated.

)

Task #4: Determination of Health Effects of Indoor Air Pollution

Occupational and residential studies of most indoor pollutants have not

produced adequate data to determine specific health effects and exposureresponse relationships for pollutants found in indoor air. Only limited

data are available to define the acute and chronic health effects from low

level exposures to essentially all of the indoor air pollutants.

Generally, such effects are extrapolated either from occupational exposure

studies or from animal toxicity studies. Animal toxicity studies are in

progress on some indoor air pollutants, (e.g., perch loroethy 1 ene

,

dich loromethane, formaldehyde, and nitrogen dioxide).

Controlled human exposure studies have been initiated to obtain exposureresponse relationships for specific acute health effects from exposure to

pollutants. Such studies include responses of sensitive individuals (e.g.,

asthmatics) exposed to irritant gases such as nitrogen dioxide,

formaldehyde, and sulfur dioxide. Additional studies have been initiated

to develop biochemical markers of exposure to specific pollutants and

pollutant sources. These markers may prove useful in future

epidemiological studies.

Health hazard evaluations are documenting exposures to low levels of

numerous air contaminants, such as volatile organics. Incidents of adverse

health effects are also being reported in commercial and institutional

buildings from exposure to volatile organics, sidestream tobacco smoke,

fibers, biologically active aerosols, and allergens. Additional studies in

progress may provide further information on such associations.

38
Discussions are underway between EPA and the National Center for Health

Statistics (NCHS) on utilizing the National Health and Nutrition Evaluation

Survey III (NHANES III), planned in fiscal year 1988, to determine adverse

health effects associated with exposure to indoor air pollutants.

Task #5: Development of Effective Control and Mitigation Techniques

Mitigation and control research is being pursued for the commercialization

of energy efficient techniques to control indoor pollutant concentrations.

Current efforts include evaluating techniques to reduce po 1 lutant strengths

and block migration pathways, examining pollutant-specific removal

mechanisms, and studying ventilation processes in indoor environments.

Ventilation strategies, with and without heat recovery, air purification

devices, and architectural and material applications are appropriate in

some situations. The effectiveness of these mitigation measures is being

laboratory tested, evaluated, and mathematically modeled.

Pilot mitigation programs are being developed to test a range of approaches

for reducing excessive concentrations. The objective of these studies is

to assure the effectiveness of mitigation measures in wide-scale mitigation

programs. Mitigation measures are being studied as a function of building

characteristics, appliances used, and occupant use patterns.

The results of control and mitigation research efforts will be used to

develop consensus testing protocols, guidelines, and information for

developing voluntary standards, primarily by industry itself. Pilot

mitigation program results will be made available in reports to state and

local agencies, utilities, and other groups interested in mitigation.

39
Task #6: National Multipollutant Field Survey

A large national multipollutant field survey of indoor air pollution will

be a key component in the research program. The National Multipollutant

Field Survey will provide the data base required to develop hypotheses to

determine dose-response relationships. The survey will draw upon the

results of the previous research tasks, and survey results will focus

future research in these ongoing efforts. The survey will provide an

estimate of the range and distribution of indoor exposures to indoor air

pollutants, and identify those factors which influence their

concentrations. The impact of energy conservation practices, including

reduced ventilation rates and use of supplementary heating sources, and the

effectiveness of mitigation techniques will be studied. A National

Multipollutant Field Survey is necessary to identify and focus further

indoor air quality research efforts, to control indoor air pollution and to

assess the impact of future energy conservation.

The Field Studies Workgroup of the CIAQ will direct the planning,

development and execution of this national survey. Over the next year,

this Workgroup will coordinate the development of sample design options for

a national survey, taking into account the research on factors affecting

exposure levels of specific indoor air pollutants (e.g., climate, pollutant

sources, ventilation). The Workgroup will also evaluate and coordinate the

CIAQ agencies' research efforts in field testing and participation in

regional indoor air quality studies. These coordination efforts will help

ensure that this Federal research effort will provide the necessary basis

for conducting a national field survey.

40
The Field Studies Workgroup will also review current health studies, and

recommend various options for obtaining health effects information,

including a possible joint survey in conjunction with the NCHS NHANES III

study

.

By the end of 1985, the Workgroup plans to present various options for a

national indoor air field survey to the full CIAQ for review and

implementation

.

Future Research Needs of the Major Tasks

Current federally sponsored research is addressing, in a limited way, each

of the six previously identified tasks. Because of the nature of the

indoor air pollution problem, a much more comprehensive program is required

by both the public and private sectors. The following strategy is directed

at overall program needs , with the CIAQ and its workgroups providing a

central coordinating function in the development process. Federal agencies

will collaborate in the development and accomplishment of this program

according to their missions, expertise, and budgetary capacity.

Each of the six research tasks discussed previously is essential to the

definition of current and future trends in indoor pollutant exposure, the

consequent risk, and the most effective mitigation techniques. In addition

to the current research tasks described in the previous sections, the

following research needs must also be pursued.

Task #1: Sources and Environmental Factors Affecting Human Exposure

- Initiate research efforts to identify and quantify sources

of indoor allergens and organic compounds

41
Expand efforts to quantify sources and pathways of

combustion products, radon, and formaldehyde

Investigate environmental factors (e.g., air exchange rates,

structural characteristics) affecting occupant exposures to

indoor air pollutants

Task #2: Characterization of Indoor Air Quality

Methods Development and Field Testing

Develop monitoring instrumentation, both active and passive,

for volatile organic pollutants, allergens, microorganisms,

particulates, NO 2 and CO

Refine, field tests, and transfer to the commercial market

instrumentation for all of the above

Develop survey questionnaires and protocols

Quality Assurance

Develop quality assurance programs, similar to that in place

for radon, for the important chemical and biological

pollutants to assure that exposure measurements made by

various laboratories in the United States and elsewhere are

comparable

Analytical Methods and Modeling

Develop standardized techniques for data analysis that

assure validity and accuracy

42
Improve and validate existing multipollutant indoor air

quality models

Data Base

Expand data bases to include measurement technologies and

health effect surveys

Task #3: Impact of Energy Conservation

Develop predictive models for determining the effects of

building design and energy conservation practices on future

indoor pollution exposures

Refine passive samplers for multi-zone infiltration and

ventilation studies

Continue development of techniques to perform air

infiltration, ventilation, and ventilation effectiveness

measurements in commercial and institutional buildings

Task #4: Health Effects

Conduct chronic toxicity studies on laboratory animals

Study populations particularly sensitive to chemical or

microbial indoor air pollutants

Develop biochemical markers for exposure to pollutants,

(e.g., urinary cotinine for passive tobacco smoke and

urinary hydroxy lpro 1 ine for NO2

)

Evaluate the toxicity of low level exposure to particulates

and other chemicals both individually and in combinations

Develop and conduct appropriate epidemiological studies for

indoor pollutants, (e.g., radon and formaldehyde)

43
Utilize more sophisticated approaches to study the health

effects of pollutants such as N02> CO and formaldehyde

Evaluate the use of CO2 in large buildings to predict

complaints of tight building/sick building syndrome

Task #5 : Pollutant Control

Develop and evaluate source control and mitigation measures

for risk reduction and cost effectiveness for a broad range

of indoor environments and pollutants

- Validate minimum ventilation requirements to support

consensus guidelines designed to provide acceptable health

and comfort levels in indoor environments.

Task #6 : National Multipollutant Survey

Develop and conduct a multipollutant field survey to

determine the national distribution of indoor exposures and

associated health effects

- Utilize survey results to design and conduct specific

studies to obtain additional information about health

effects, energy conservation, pollutant sources and control

options

In summary, a major national effort is needed to implement this

comprehensive indoor air quality research strategy. Action is needed by

both the public and private sectors ! The CIAQ's role in addressing this

problem will be to coordinate Federal research efforts, and to develop new

mechanisms for interacting with state and local governments and the public

and private sectors. Through the CIAQ workgroups, research conducted in

44
other programs, such as the National Toxicity Program, will be used to

augment indoor air quality efforts. The CIAQ will also periodically

evaluate research results to reassess health risks associated with indoor

air pollution. Finally, the CIAQ will make a concentrated effort to assure

technology transfer through dissemination of research results and

participation in symposia, public meetings, and workshops.

NBS COMPETENCIES IN INDOOR AIR QUALITY RESEARCH

Under its general mission of developing and supplying technical data,

standard reference materials, evaluation methods and measurement methods,

several centers of NBS have expertise needed to further indoor air quality

research. Several are currently contributing, and have contributed to

programs supported by EPA, DoE, CPSC and others. Listed below are some

Centers and Divisions which have expertise. These NBS capabilities listed

are those included in the CIAQ research strategy as future needs.

Center for Analytical Chemistry

Gas and Particulate Sciences Division

Organic Analytical Research Division

Sensor R&D, including personal monitors,

Standard pollutant concentration reference materials,

Standard field sampling protocols

Pollutant concentration measurement methods

Center for Chemical Physics

Methods of source emission determinations

Dioxin formation and modeling

Center for Radiation Research

Radon measurement methods

Radon concentration reference materials

Radon emanation from materials

Center for Building Technology

Infiltration rate measurements

Indoor air flow measurements

Ventilation system measurements

sys t ems

45
Ventilation effectiveness measurements

- Air movement measurements

Development ofmodels of building systems for predicting

contaminant levels outs ide-to- ins ide and room-to-room)

Validation of models

- Air cleaner performance evaluation

Combustion appliance emanation rate measurements

Emanation rate measurements from materials

Center for Fire Research

- Combustion products emanation rate measurements

Smoke migration measurements within and between

Modeling of inside pollutant concentrations

model validation.

SUGGESTED NBS ROLE

The role of NBS in supporting research in the area of IAQ should remain

within the general NBS mission. Health effects determinations are a vital

part of the necessary research, but are not in the NBS mission. Many

competencies exist outside NBS which overlap the NBS mission, so it is

unrealistic to expect NBS to obtain an exclusive mandate for all IAQ work

within its mission. There are many specific areas where NBS is uniquely

qualified, and these should be stressed. Field measurements are an

important need of IAQ. NBS work on field measurements is best done in

support of instrument development and validation work and to develop

suggested field protocols. Specific areas where NBS has a partial and

sometimes unique role are listed below:

- Standard concentration reference materials

- Sensor and instrument development for sampling

organics

particulates

radon

inorgan ics

- Analytical methods for air sampling

spaces

from fires and

46
organics

radon and daughters

heavy metals and other inorganics

Certification of instrument system accuracy

Concentration modeling in complex systems in both micro and

macro environments

Tracer gas methods for all kinds of ventilation measurements

- Pollution emanation rate measurement methods and data

collection

RECENT CBT RESEARCH ON INDOOR AIR QUALITY

In FY 1984, CBT had six projects which can be included as IAQ or IAQ

related. The NBS funded projects are listed:

1. IAQ in Office Buildings.

2. Expert System for Diagnosis for Air Leakage

3. Large Building Air Movement

In addition, DoE funded two projects:

1. Urea-Formaldehyde Foam Insulation Summary and,

2. Wall System Air Leakage Research.

and CPSC funded one project:

1. Pressed Wood Model Evaluation

These projects are briefly summarized in Appendix A. The total effort was

$421. 5K.

In FY 1985, DoE continues to fund one project:

1. Infiltration Measurements in Large Buildings.

47
CPSC continues funding of one project:

1. Pressed Wood Model Evaluation.

And EPA funding was received for one project:

1. Indoor Air Quality Modeling

and EPA also helped fund the Pressed Wood Model Evaluation project.

The total funding for the FY 1985 projects is $331. 25K. This is a decrease

from FY85. However, it should be noted that the entire amount is funded by

other agencies. These projects are summarized in Appendix B.

OUTSIDE FUNDING POSSIBILITIES FOR FY86

EPA had $2M for IAQ in FY 1985. EPA expects to have $3M for FY 1986, but

congress has not yet acted on its budget. NBS has received FY 1985 EPA

funding, with increased funding expected to continue in FY 1986 and 1987.

CPSC has a nearly $2M, and also funded CBT in FY 1985. This funding is

expected to continue in FY 1986.

DoE has funded CBT research for many years. DoE had approximately $1.7M in

FY 1985 to perform IAQ research related to its energy conservation

functions. CBT had FY 1985 funding and a larger amount is also expected

for FY 1986.

NBS internal funding in the amount of $96K has been received to develop

some of the more basic elements of IAQ modeling work and to help position

CBT's technology to be even more useful to OA sponsors in this important

national problem.

48
EXPECTED CBT RESEARCH IN FY86

Although a FY86 funding is not altogether firm, indications are strong that

five projects will be funded. They are summarized in Appendix C. That

expected funding totals $657. 25K. It is expected that some additional

projects may also be funded during FY86.

CBT RESEARCH PLAN

The CBT p lan will build upon the IAQ work to date. In imp lementing and

executing the plan, CBT will cooperate with other NBS units wherever

appropriate. Several proposals have been developed by CBT divisions which

show the capabilities and interests in indoor air quality. These proposals

are not yet funded, but have been discussed within CBT and with EPA, DoE

and CPSC as appropriate. They are summarized in Appendix D.

The new indoor air quality program was included in the CBT Long Range Plan

in November 1984. It was revised in November 1985 in the National Research

Council Board of Assessment Panel for Building Technology Vol. II. This

plan is repeated below and should be the research plan for IAQ work in CBT.

Since much of CBT"s work depends upon other agencies, and other forms of

outside support, the execution of the plan will depend largely upon outside

funding, and CBT's vigorous proposal activities. Ranges of annual funding

have been added to the milestone chart. These amounts could be efficiently

employed.

Indoor Air Quality

Objective : To provide research and technical data to assist in standards

development and control requirements, and to encourage new control

developments

.

49
To develop comprehensive indoor air quality (IAQ) models to assist

standards development. Validate the models through laboratory and field

research in ventilation, source emission, and control. Develop measurement

systems for field and laboratory research and suggest new ventilation

strategies

.

Background : Several pollutants have been identified in dwellings,

commercial buildings, hospitals, government buildings, etc., at levels

above those considered to be appropriate in industrial workplaces. For

example, high levels of radon, CO, formaldehyde, NC> 2

j tobacco smoke, and a

wide variety of organic compounds have been measured. Health effects of an

acute nature have been identified and chronic health effects have been

suggested. Estimates indicate that as many as 20 million people may be at

risk from airborne contaminants over their lifetimes.

The information to date suggests a serious and urgent need to understand

and improve IAQ in the public interest.

CBT is uniquely qualified to address the interaction of IAQ control systems

with the building HVAC system and the building envelope system so that

better assessment of IAQ controls can be made in terms of energy impact,

environmental changes affecting health and comfort, and life-cycle cost

implications

.

Technical Approach : CBT work will assist other agencies and the private

sector in developing needed guidelines, standards, and technical data for

improved IAQ through control strategies, equipment design, and building

design. CBT will build upon its past leadership in developing complex

models capable of predicting pollutant levels from sources introduced into

buildings from outdoor air, and those generated inside from point sources,

50
such as a gas range, as well as area sources, such as from floor and wall

) coverings. Several different models will be developed to predict indoor

contaminant levels as functions of emission, dilution, intra-building

movement, absorption, and settling. The internal mixing effects within

rooms and between rooms will also be analyzed, as will the effects of

infiltration and forced ventilation. The effect of internal air mixing and

ventilation effectiveness will also be analyzed. The models will permit

the evaluation of the effects of contaminant removal mechanisms, through

interaction with the building materials and furnishings, control devices,

ventilation strategies, and interactions with other indoor air

contaminants. The completed models will enable accurate predictions of

indoor levels of all important contaminants in all significant types and

locations of structures so that appropriate control strategies can be

developed. The models will be verified by using data from laboratory and

field studies at CBT as well as from information obtained by other

researchers. Sensitivity analysis is expected to suggest areas of specific

research where additional knowledge is needed.

CBT will use its extensive capabilities in ventilation and infiltration

measurement system development in residences and office buildings to

evaluate ventilation strategies and controls, including heat recovery

devices, suggest novel control strategies, and develop measurement systems

for use by others.

The lead roles are with EPA, CPSC, DoE and NIOSH. CBT has demonstrated

capabilities in thermal and ventilation modeling, and infiltration

measurement, and has been called upon in these and many other related areas

by these agencies.

51
Interactions : CBT has many effective methods of delivering its technical

results to users. Interagency reports to sponsors are always written. CBT

representation on the IAQ Interagency Committee is effective for

coordination and delivery of research results. Many CBT professionals are

active in ASHRAE and ASTM, which provide private sector technical programs

of wide interest and reputation, as well as vigorous voluntary standards

generation. These standards are widely used by governments at all levels.

CBT research is also published in many other referenced documents.

Resources : CBT has been active in these areas in the past and will build

on this work to provide a more comprehensive IAQ program. Further work in

the period beyond five years will also be necessary. A total of 10 years

is expected.

Staffing needs to be expanded to conduct a significant program. For

expansion, two professionals with chemical background would be needed. The

program will involve the Building Physits, Building Equipment and Building

Materials Divisions.

52
MILESTONES

TIME TABLE

Planned Activities 86 87 88 89 90

Model Development

Model Validation

Pollutant Characterization

Formaldehyde

Organic Contaminants

Field Measurements

Ventilation Effectiveness

Commercial Building Protocol

Ventilation System Performance

Control Systems

Air-to-Air Heat Exchange

Test Method

Particulate Air Cleaner

Test Method

Gaseous Air Cleaner

Test Method

Effort

S700K S750K S800K S800K S800K

$90 OK $900K S1000K SHOOK SHOCK

53
REFERENCES

[1] Moschandreas , D. J. and Morse, S. S . , ; "Exposure Estimation and

Mobility Patterns;" 72nd Annual Meeting of the Air Pollution Control

Associat ion; Cincinnati, OH; 1979.

[2] Proceedings of the Third International Conference of Indoor Air Quality

and Cl irnatp ; Swedish Council for Building Research; Stockholm, Sweden;

August 20-24, 1984; Five volumes.

[3] "Indoor Air Pollution;" Environment International ; Pergamon Press;

1982; Volume 8, Nos. 1-6.

"

[4] Indoor Pollutants ; National Academy of Sciences; National Academy

Press; Washington, DC; 1981.

[5] Spengler, J. D. and Steton, K.; "Indoor Air Pollution: A Public

Health Perspective;" Science , July 1983; Volume 221, pp . 9-17.

[6] Turiel, I., Fisk,W. J., and Seedall, M.; "Energy Savings and CostEffectiveness of Heat Exchanger Use As An Indoor Air Quality

Mitigation Measure in the BPA Weatherization Program;" Energy ; 1983;

Vo 1 . 8(5); pp. 323-335.

[7] Indoor Air Quality Research Strategy ; U.S. Interagency Committee on Indoor Air Quality; U.S. Environmental Protection Agency, Office of

Research and Development; Washington, DC; December 1, 1984.

[8] Ventilation for Acceptable Indoor Air Quality ; ASHRAE Standard 62-

1981, American Society of Heating, Refrigerating, and Air-Conditioning

Engineers; Atlanta, GA; 1981.

[9] National Primary and Secondary Ambient Air Quality Standards ; U.S.

Environmental Protection Agency, Code of Federal Regulations, Title

40, Part 50.

[10] Morey, P. R. and Runders, R. E.; Proceedings of the Third

International Conference on-Indoor Air Quality and Climate; Stockholm,

Sweden; August 20-24, 1984; Volume 3, pp . 247-252.

[11] ASHRAE Handbook . Fundamentals, Atlanta, GA, 1981.

[12] ASHRAE Handbook . Equipment, Atlanta, GA, 1983.

[13] Criteria for Recommended Standards . (Series); National Institute of

Occupational Safety and Health, U.S. Department of Health, Education,

and Welfare; various dates.

[14] Criteria for Recommended Standard — Occupational Exposure to

Forma ldehyde; National Institute of Occupational Safety and Health,

U.S. Department of Health, Education, and Welfare; Publication No. 77-

125, References 57-93.

[15] Occupational Safety and Health Administration Asbestos Regulations , Code of Federal Regulations, Title 29, Part 1910.1001.

54
[16] Threshold Limit Values of Airborne Contaminants

,

American Conference

of Governmental Industrial Hygienists, Cincinnati, OE.

[17] American Industrial Hygiene Association, Community Air Guides .printed

in the Association's Journal as indicated below:

Acrolein and Formaldehyde, AIEAJ 29(5): 505-512, Sept. -Oct., 1968

Beryllium, AIEAJ 29(2): 189-92, Mar. -Apr., 1968 Phenol and Cerscl

AIEAJ 30(4): 425-428, July-Aug., 1969.

[18] ?co<i and Drug Administration. U.S. Department of Health, Education and

Welfare, Maximum acceptable level of ozone, Code of Federal

Regulations, Title 21, Part 801.415 (21 CPR 801.415).

[19] Environmental Protection Agency Regulations for Asbestos . Code of

Federal Regulations, Title 40, Part 61, Subparts A and B,

[20] Rule for Manufactured Housing Construction and Safety Standards. T.S

.

Department of Housing and Urban Development; Effective Februarv 15,

1985.

[21] "Performance and Application of Electronic Air Cleaners in Occupied

Spaces" P. E. McNall, Jr. et ai ASERAE Journal, May 1965.

[22] Radon in 3uildings; National Bureau of Standards Snecial Publication

581; 1980.

[23] Hone Weatherization and Indoor Pollutants: Environment and Power,

3onneville Power Administration, Department of Energy, E&P 3-7;

September 1984.

[24] Archer, V. E. et al.; ’’Uranium Mining and Cigarette Smoking Effects on Man"; Journal of Occupational Medicine : 1973; Volume 15, pp. 204-211.

.2t. Maclaren, J. "The Reduction of Radioactivity Found in Bencroft

,

Ontario and its Environs" Atomic Energy Control 3oard, Canada 1979.

[26] Fisk, WU. et. ai. "Indoor Air Quality Control Techniques: A Critical

Review" 3uilding Ventilation and Indoor Air Quality group, Lawrence

Berkeley Laboratory, Berkeley, CA, Mar. 1984.

[27] National Emission Standards for Hazardous Air Pollutants . Cede of

Federal Regulations, Title 40, Part 61, Subpart M.

[28] "Symposium on Health Aspects of Indoor Pollution"; Bulletin of the New

York Academy of Medicine : New York; December 1981; Volume 57, No. 10.

[29] Pielert, J. and Mathey, R. ; Guidelines for Assessment and Abatement

of Asbestos-Containing Materials in 3uildings: NBSIR 83-2688; National

3ureau of Standards; Gaithersburg, MD; May 1983.

[30] Smoking, and Health; A Report of the Surgeon General, U.S. Department

of Health, Education, and Welfare; Publication No. PRS 79-60066.

5 5
[31] Ferris, B. G. Jr., Dockery, D. W. and Ware, J.; Proceedings of the

Third International Conference on Indoor Air Quality and Climate ; Stockholm, Sweden; August 20-24, 1984, Volume 2, pp. 309-311.

[32] Tr ichopoulos , D., et.al.; Lancet II ; 1983; pp. 677-678.

[33] Indoor Air Pollutants-Exposure and Health Effects Assessments ; World

Health Organization Working Group Report; Copenhagen, 1983.

[34] Mortality and Morbidity Weekly Report: Centers for Disease Control;

Atlanta, GA; June 22, 1979; Volume 28, Number 24.

[35] Hinkle, L.E. Jr. and Murray, S.H.; "The Importance of the Quality of

the Indoor Air"; Bulletin of the New York Academy of Medicine : New

York; December 1981; Volume 57, No. 10, pp 827-844.

56
Appendix A - FY84 Project Summaries

1. Title : Indoor Air Quality in Office Buildings

Funding : $50K (NBS

)

Ob i ec tive : Determine general needs of commercial office buildings and the

specific degree of space mixing in buildings and its effects on indoor air

quality (IAQ).

Problem Significance : Commercial building problems have had little

attention to date, but growing problems are emerging. Several buildings

have been evacuated due to ''building sickness syndrome," a term attached to

poor air quality causing occupant complaints. In some cases, very little

ventilation air was provided. In others, specific biomatter was

multiplying in the HVAC systems, and affecting the occupants. The

increased uses in buildings of materials which outgas are also suspected.

Definitive IAQ standards and design practices are needed.

Technical Approach : Technical support was provided to other CBT projects.

Work with EPA on their program reviews and with DoE and NIBS identified

other specific needs. The focus was on measurement methods for indoor

contaminants and ventilating systems for commercial office buildings. What

should be measured? What measurement techniques should be used, etc.

Product in FY84 :

1. Invited paper for Engineering Foundation Conference 3/84

on Ventilation in Enclosed Spaces, titled "The Impact

of Building Codes and Regulations on Indoor Air Quality."

2. Invited paper for the American Conference of 6/84

Governmental Industrial Hygienists on "Ventilation

Concepts for Office Buildings."

57
2. Title : Expert System to Diagnose Air Leakage Problems in Complex

Buildings

Funding : $50K (NBS)

Problem S ign

i

f iV an r.p: Although air leakage plays extremely important roles

for the transfer of heating/cooling energy, humidity and contaminants from

one zone to the next, currently there is no adequate procedure to predict

and control the movement of building air under naturally ventilated

conditions and to diagnose air leakage problems in buildings. NBS has

recently developed a sophisticated computer program called TARP to simulate

simultaneous transfer of air, heat, moisture and contaminants on a dynamic

basis. Presently the program is a research tool and not suitable for the

use in design and control processes whereby the building envelope and HVAC

system are to be optimized from the standpoint of indoor air quality,

thermal environment and annual energy consumption. Introduction of the

Expert System is needed to expedite the decision process.

Technical Approach : The first phase of this research program is to develop

a frame work for using the concepts of the Expert System in building air

algorithms in TARP for the development of decision processes for diagnosing

air leakage and ventilation problems in complex buildings. Representation

of air motion, its phenomenological characteristics as well as known

physical principles, will be compiled into a knowledge data base, which can

be used in the decision making algorithms.

Products in FY84 :

1. "Expert Systems and Air Infiltration" 9/84

3. Tit le : Large Building Air Movement

Funding : $100K (NBS)

Obiective : Develop predictive modeling and measurement methods for the air

58
movement in large buildings.

Problem Significance : Large buildings have complex air movement patterns.

The understanding of these air movement patterns is required for the

assessment of their energy performance, for the determination of indoor air

quality, for understanding moisture migration and for smoke control. It is

difficult to either analytically model this air movement or to

experimentally measure the movement of air in multizone buildings.

Technical Approach : The NBS developed Thermal Analysis and Research

Program (TARP) was used to predict the interzone air movement in several

large office buildings in which NBS had measured the air infiltration and

ventilation. The results of this analysis was used to design a field test

to validate the prediction of TARP. The NBS developed automated air

infiltration monitoring system for large buildings was used to measure the

migration of a tracer from various zones of the building to adjacent zones.

The results of these measurements will be used to validate the predictions

of TARP.

Products in FY84 :

1. "Air Flow Calibration of Building Pressurization Devices" 10/84

4. Title : Urea-Formaldehyde Foam Insulation

Funding : $50K (DoE)

Objective : The objective of this project is to provide a review of the

technical issues concerning urea-formaldehyde foam insulation in walls and

ceilings of residential construction. This includes a review of the

properties and composition of these insulations and techniques for their

measurement, a review of remedial measures such as foam removal to

eliminate or reduce problems associated with its presence, and an

59
identification of research needs to resolve the problems caused by ureaformaldehyde foam in residences.

Problem Significance : The Consumer Produce Safety Commission determined in

March 1982 that urea-formaldehyde foam insulation presents an unreasonable

risk of injury to persons living in homes containing this material because

of the risk of acute and chronic illness from the gas released by the foam.

The Canadian Government has prohibited the use of urea-formaldehyde foam

insulation in residences and has made funds available for its removal. The

cost of removal of urea-formaldehyde foam insulation from the walls of a

residences in the United States has run from about $5,000 to $20,000.

It is estimated that there are about 500,000 homes in the United States

that are insulated with urea-formaldehyde foam insulation. In the worst

situation, some people have removed this insulation from their homes.

Remedial measures including foam removal to eliminate or reduce problems

associated with its presence have not been reviewed in the United States.

Other countries such as Canada and Australia have addressed this problem.

Technical Approach : The review was based on existing information and

building practices. It focused on technical issues concerning problem

identification such as properties and composition of urea-formaldehyde foam

insulation, the type of residential construction, and interactions between

the foam and wall components. The review also focused on remedial measures

to be taken to eliminate or reduce problems.

The information obtained in the study was also used as the basis for

discussions concerning possible revisions of ASTM C951 "Standard

Specification for Urea-Formaldehyde-Based, Foamed- in -P lace Insulation." In

this regard, an NBS research staff member chaired the ASTM C16.23 task

60
) group on urea-formaldehyde foam insulation (Spring 1984).

Products in FY84 :

1. "Urea-Formaldehyde Foam Insulations: A Review of 9/84

Their Properties and Performance"

5. Tit le : Wall Systems Air Leakage Research

Funding : $100K (DoE)

Objective : To develop test methods for evaluating the movement of air into

and within large commercial buildings and to determine the efficiency of

the ventilation systems of commercial buildings in providing a mechanism

for removing contaminants at a minimum energy cost.

Problem Significance : In comparison to residential buildings, little data

exists on the air leakage and air movement in large commercial structures.

What data does exist indicates that modern office buildings are relatively

tight and are operated with little outside air. Such buildings may not be

providing a sufficient quantity of outside air to remove contaminants

generated in the building. Even buildings which have a total air exchange

rate sufficient to remove contaminants, may have zones which require little

heating or cooling energy and therefore use small amounts of air.

Technical Approach : A test method was developed for measuring the

efficiency of ventilation in modern commercial buildings. This method

determined the minimum amount of air exchange which is effective in

removing contaminants from the work space. The method was based on the

injection of a tracer gas into various zones of the building and

determination of the build-up and decay of the tracer gas in the work space

and in the exhaust air. Initially the NBS automatic air infiltration

system developed for application to large buildings was used. Tests were

61
made in at least three different commercial buildings and the results were

used to determine the effectiveness of the ventilation systems.

Products in FY84 :

1. "Measurements of Ventilation Rates and Ventilation 5/85

Effectiveness"

2. "Ventilation Efficiency in Mechanically Ventilated 8/85

Offices"

6. Title : Pressed Wood Model Evaluations

Funding : $71.25K (CPSC)

Obiective : The objective of this project is to evaluate the ability of an

indoor air quality (IAQ) model developed by the National Academy of

Sciences to predict the level of formaldehyde in controlled laboratory

situations and field situations due to pressed wood products.

Problem Significance : Formaldehyde is a contaminant which is introduced

into buildings by building products such as plywood, particle board and

wood paneling. Models currently being used by CPSC to predict formaldehyde

levels have not been adequately tested. There are simplifying assumptions

made in developing these models which should be checked. An evaluation of

these models is required to determine their ability to predict the

formaldehyde levels in order to determine the nature of the errors

introduced in the analysis being performed by CPSC.

Technical Approach : NBS will evaluate the indoor air quality model in the

two computerized forms currently being used by CPSC: a one compartment

model which treats the house as a single unit and determines the average

formaldehyde concentration; and a two compartment model which divides the

house into two compartments and determines the average formaldehyde

concentrations in each compartment.

62
A series of controlled experiments in a chamber in the laboratory will be

performed. The chamber was constructed in such a way that the temperature,

humidity, air infiltration and the ventilation efficacy could be

controlled. The chamber was calibrated to determine its absorption and

emission characteristics of formaldehyde. Then a series of conditioned

pressed wood products whose formaldehyde emission rate will be determined

by the Formaldehyde Emission Surface Monitor (FESM) developed by Oak Ridge

National Laboratory will be introduced in the chamber. The formaldehyde

levels in the chamber will be measured and compared with the predictions

made by the IAQ model.

Products in FY84 :

1. NBSIR entitled "Evaluation of Indoor Air Quality Models 2/85

for Predicting Formaldehyde Levels due to Pressed Wood

Products

63
) Appendix B - FY85 Project Summaries

1. Title.: Inf iltration/ Ventilation - Large Buildings

Funding : $115K (DoE)

Objective : To develop test methods for evaluating the movement of air into

and within large commercial buildings and to determine the efficiency of

the ventilation systems of commercial buildings in providing a mechanism

for removing contaminants at a minimum energy cost.

Problem Significance : In comparison to residential buildings, little data

exists on the air leakage and air movement in large commercial structures.

What data does exist indicates that there is a wide range of air leakage

rates in large buildings. Some large office buildings have been found to

be so leaky that it is difficult to maintain comfortable interior

conditions. At the other extreme, if a modern office building is

relatively tight, there may be times at which it is operated with little

outside air. Some buildings may not be providing a sufficient quantity of

outside air to remove contaminants generated in the building, and in other

cases buildings may be overventilated resulting in a waste of energy. Even

buildings which have a total air exchange rate sufficient to remove

contaminants may have zones which require little heating or cooling and

therefore receive small amounts of air. Also, the design of air

distribution systems and the placement of internal partitions may result in

uneven distribution of what would otherwise be an adequate amount of

ventilation air.

Technical Approach : Test methods already developed for measuring the

efficiency of ventilation will be applied to modem commercial buildings.

These methods will determine the amount of air exchange which is effective

in removing contaminants from the work space. The methods are based on the

injection of tracer gas into various zones of the building and

64
) determination of the build-up and decay of the tracer gas in the work space

and in the exhaust air. Initially the NBS automatic air infiltration

system developed for application to large buildings will be used. The

procedure will be evaluated by testing at least three different commercial

buildings and using the results to determine the effectiveness of the

ventilation systems.

NBS will also work with Brookhaven National Laboratory in (at least) one of

the commercial buildings being studied to compare automated tracer gas

infiltration and ventilation measurements with those obtained using passive

perf luorocarbon tracer samplers.

Products in FY85 ;

1. NBSIR, "Simultaneous Room/System Modeling and Water/ 3/85

Pollutant Migration".

2. NBSIR, "Validation of TARP". 3/85

3. Technical paper for ASTM, "Air Infiltration and Ventilation 5/85

in Large Office Buildings".

2. Tit le : Pressed Wood Model Evaluation (continuation of FY84 project)

Funding : $116. 25K

Ob iective : Same as FY84.

Problem Significance : Same as FY84.

Technical Approach : Same as FY84.

Products in FY85 :

1. NBSIR entitled "Validation of Models for Predicting 10/85

Formaldehyde Concentrations in Residences due to Pressed

Wood Products."

65
3. Title : Development of a Plan for a General Indoor Air Pollution

Concentration Model

Funding : $50K (EPA)

Ob i ect ive : The purpose of this proposal is to develop a framework for a

comprehensive computer model to simulate dynamic pollutant movement and

concentration variations in buildings.

Problem Significance : EPA needs a general and comprehensive model which

can predict the extent, severity, and duration of indoor air pollution.

Such a model, when developed, should be useful in the evaluation of various

indoor air quality control systems as well as for policymaking processes.

Technical Approach : Most of the previous work reported for indoor air

pollution modeling is based on a simplistic one-room dilution model which

ignores the thermal effects and mixing dynamics.

A comprehensive analysis of pollution migration in buildings requires

accurate simulation of all processes affecting pollutant concentration.

These processes are infiltration, generation, dilution, reaction, removal,

and exfiltration. NBS has recently developed a comprehensive dynamic

building simulation model called TARP. In addition to detailed thermal

conduction and radiation calculations, TARP computes infiltration and

interroom airflows by considering the flows through all openings (doors,

cracks, etc.) and requires a mass balance in each room. It can serve as a

framework for adding the other components of the contaminant equation.

TARP will have to be expanded primarily in the following areas: (1)

Detailed models will have to be developed for generation, reaction, and

removal of various contaminants. (2) An air handling/ducting system model

is needed to complete the simulation of forced interroom airflows and

66
filtration devices. (3) The effects of interroom convection must be

understood so that the simplified model can be developed. This area is

primarily concerned with local air velocities, ventilation effectiveness,

and removal of contaminants which have localized sources. Detailed models

would be too time consuming to include in long-term simulation.

Products in FY85:

1. NBSIR, "IAQ Modeling Workshop Report” 4/85

2. Technical Paper, "Indoor Air Quality Status Report”.

3. NBSIR, "Indoor Air Quality Modeling, Phase I Report, 10/85

8/85

Framework for Development of General Models”.

6 7
Appendix C - Projects Expected to be Funded in FY86

1. Tit le : Inf i 1 trat ion/ Ven t i 1 at ion - Large Buildings (this is a

continuation of the FY85 project)

Funding : $120K (DoE)

Objective : Same as FY85.

Problem Significance : Same as FY85.

Technical Approach : The test methods developed in FY85 for measuring

ventilation efficiency will be applied to five office buildings.

Measurements of the distribution of contaminants in these office buildings

will also be made. The contaminants which will be measured will be C02>

CO, respirable particles in the range 0.3 to 0.5 ym, 0.5 to 0.7 ym, 0.7 to

1 ym, 1 to 5 ym, and 5 to 10 ym, formaldehyde and radon. These

measurements will produce both a data set on contaminants in office

buildings and also an assessment of the concept of ventilation efficiency

in characterizing the ability of building ventilation systems to remove

contaminants

.

In conjunction with NIOSH, NBS will study the relationship between the

level of contaminants and the operation and design of the ventilation

system in the Columbia Plaza Building. In addition to the contaminants

listed above, NIOSH will measure the levels of micro-organisms and

allergens in the building. These data will be analyzed by NBS and NIOSH to

determine the relationship between the performance of the ventilation

system and the levels of indoor contaminants.

Products in FY86 :

1. NBSIR on Ventilation Efficiency and Contaminant Levels in 9/86

Five Office Buildings.

68
2. NBSIR on the Relationship of Ventilation System 12/86

Performance and Indoor Levels of Contaminants in the

Columbia Plaza Building.

2. Tit le : Evaluation of Barriers on the Emission of Formaldehyde from

Pressed Wood Products (this project is a follow on of the

FY85 formaldehyde emission project)

Funding : $75K (EPA)

Object ive : To determine the effect of remedial actions on the emission

rate of formaldehyde from pressed wood products.

Problem Significance : The emission of formaldehyde from pressed wood

products has been studied only under ideal conditions. It has been shown

that certain pressed wood products can emit large amounts of formaldehyde.

It is possible however that simple treatments of the products can reduce

the formaldehyde emission rate at little or no cost.

Technical Approach : NBS will use eight of its medium size chambers for

measuring formaldehyde emission from pressed wood products to evaluate the

effect of several simple treatments to the products on the emission rate of

formaldehyde from the products. NBS will consider treatments which can be

applied both in the manufacture of the pressed wood products and also as a

retrofit measure. The effect of barriers and absorbers such as floor

coverings and paints will be evaluated. In addition, NBS will evaluate the

emission rate characteristics of several new products of both U.S. and

European manufacture to determine their emission rate characteristics.

Each product tested will be conditioned at 23°C, 50% R.H. for a period of

two weeks. The product's normal HCHO emission rate will be measured at six

different HCHO background levels from 100 ppb to the product's shutdown

point. Two-thirds of the products will then be treated, one-third of the

69
products will be left untreated. After a period of one week, the products

will be retested to determine the initial effect of the treatment on the

products. After one month, the treated products will be retested.

Products in FY86 :

1. NBSIR on Effect of Barriers on HCHO Emission from 11/85

Pressed Wood Products.

3. Tit le : Remedial Measured for Reducing Formaldehyde Emissions and

Concentrations. (This project is also a follow on of the

FY85 Formaldehyde Emission Project.)

Funding : $57K (CPSC)

Obiective : The purpose of this study is to examine the methods available

for reduction of both emission rates and concentrations of formaldehyde.

These methods shall include, but not be limited to coatings, barriers, air

cleaning, formaldehyde removal, air exchange and product/house treatment.

Problem Significance : While the prediction of the exposure level for an

individual person is a very complicated problem, the use of the indoor air

quality (IAQ) computer models has shown that under certain conditions of

temperature, relative humidity, air exchange, loading, etc., relatively

high concentrations of formaldehyde can exist. Tests performed by NBS for

CPSC have shown that for bare pressed wood products there is a good

agreement between IAQ models and measurements in a simulated house.

A person is not often exposed directly to the emission from a pressed wood

product. For example, when particle board underlayment is used as a

flooring material it is usually covered with tile or a carpet and padding.

Another example could be a kitchen cabinet made with medium density

70
fiberboard (MDF) where the MDF is usually finished with a coating or

covered with another material.

Two important pieces of knowledge are lacking which CPSC needs in order to

assess solutions to high formaldehyde concentration problems. The first is

the effectiveness in reducing formaldehyde emission rates of coatings and

other materials used to cover pressed wood. The second is the

effectiveness of other actions which can be taken to reduce these

concentrations to acceptable levels in those homes which exhibit a problem.

Technical Approach : This project will be divided into three tasks:

1.

) Examine methods for formaldehyde concentration reduction;

2.

) Experimentally test and validate those methods which appear most

promising and for which insufficient testing has been conducted to

allow reasoned evaluation of effectiveness; and

3.

) Identify the most cost-effective, presently available methods for the

various expected cases (for example sources, conditions, etc.) and

identify where further research is needed.

Products in FY86 :

1. Letter Report: Identification of Formaldehyde Reduction 2/86

Methods

.

2. Letter Report: Evaluation of Remedial Measures for 7/86

Reducing Formaldehyde Emission - Test

Results

.

3. NBSIR: Effectiveness of Remedial Measures for Reducing 9/86

Formaldehyde Emission for Pressed Wood Products.

4. Tit le : A General Indoor Air Pollution Concentration Model. (This is a

continuation of the FY85 porject on IAQ modeling.)

71
Funding : $100K (DoE)

$100K (EPA)

Ob i ec t i v

e

: The purpose of this proposal is to develop a comprehensive

validated computer model to simulate dynamic pollutant movement and

concentration variations in buildings.

Problem Significance : Same as FY85.

Techni cal Approach : The model framework resulting from the FY85 work will

be used to develop a comprehensive indoor air pollution predictive model.

It will cover one-compartment fully mixed (one-node) and multi-compartment

fully mixed cases. It will also include the two-node cases for one- and

multi-compartment cases. In addition, convection simulations will be

covered for the two- and three-dimensional cases for a single compartment.

Several pollutants will be covered.

Products in FY86 :

1. NBSIR for the General Model for Predicting Indoor Air 9/86

Pollution in Buildings.

5. Tit le : Micro-Modeling of Contaminant Concentration in a Space

Funding : $96K (NBS

)

Ob i ec t i v e : To develop models for predicting the distribution of

contaminants within spaces in buildings.

Project Significance : Many pollutants are released into a space from point

sources and the distribution of such pollutants within a space is not

uniform. Cooking at a range, hobby activities, smoking, and business

machines are examples of such pollutant sources. Some pollutants are also

be 1 ieved to affect health when relatively high concentrations are inhaled

for only a short time. Therefore there is a need to be able to predict

areas where high concentrations will exist. Most modeling to date assumes

72
complete mixing in a space or employs a two-compartment assumption with

uniformity within each compartment. There is a need for validated models

for the short-term exposures to pollutants which can result from such

activities as cooking, for example, to which a housewife could be exposed

as she stands near a range or side-stream exposure of non-smokers from

smokers in a room. Certain subpopulations, for example small children,

also spend much of their time in areas not typical of the average

conditions in the space - i.e., near the floor. Such micro-models can also

be used to predict ventilation efficiency in office buildings which would

aid in the design of more effective office ventilation systems.

Technical Approach : Some recent Japanese papers have considered the micromodeling problem. This research has shown that it is feasible, using first

principles, to predict the distribution of contaminants in a space. This

information will be used as a basis for developing simplified micro-models

which will be verified by experiments within one of CBT^s environmental

chambers. Typical environmental conditions and pollutant source

distributions found both in residences and office buildings will be

modeled using the techniques developed by the Japanese researchers. From

the results of these models, two typical situations will be simulated in

the two-room chamber used for formaldehyde model validation and the results

compared with the prediction of the models.

This information will be needed as part of larger IAQ modeling effort being

carried on for EPA and DoE, which involves room-to-room and indoor-outdoor

predictions

.

Products in FY86 :

1. NBSIR on models for predicting the distribution of 9/86

contaminants in spaces.

73
Appendix D - Unfunded Proposals Showing CBT Capabilities

1. Title ; Effects of Building Materials on Indoor Air Quality

Funding Proposed : $200K

Ob i ec t iv e : To provide pollutant emanation rates for various pollutants

with practical sized samples.

Problem Significance : In order to help indoor air quality (IAQ) control

options, data is needed on 1) the emission of contaminants from materials

in the structure and furnishings of buildings, and 2) the abilities of

these materials to absorb and re-emit contaminants. While valuable data

can be obtained from small-scale experiments on individual materials, some

confirmatory data will be needed from large specimens which may include

materials systems in simulated indoor air environments.

Technical Approach : Samples of a range of common organic (plastic)

materials used in buildings will be obtained and emissions from them will

be determined in small-scale experiments using very sensitive techniques

such as gas chromatography/mass spectrometry. Then, in conduction with the

project officer, a selection will be made of organic materials of

particular importance for further study. An investigation of the rates and

extents of absorption of vapors emitted from the selected organic materials

by other building materials will be investigated to provide data for use in

model development. The work will include characterization of the building

materials in terms of specific surface area and porosity and adsorption

isotherms for important vapors, so that variations in these characteristics

can be taken into account in the models.

The work will be carried out in three phases. In Phase I, small-scale

experiments on a broad range of materials to identify the main emissions

from them will be carried out. In Phase II, more detailed investigations
will be carried out to provide more quantitative data on emissions from a

small number of selected organic materials, with the absorption of the

vapors by other building materials being investigated. In Phase III, the

larger chambers available at NBS will be used for simulating the emission

and absorption of vapors by materials systems in buildings.

Products Expected : Reports on results in suitable form.

2. Title : Method for Measuring the Efficiency of Devices for Removing

Gaseous Contaminants from Air Streams

Funding Proposed : $100K/year for two years

Ob iective : To develop methods for measuring the efficacy of filters to

remove gaseous contaminants.

Problem Significance : Activated charcoal filters and filters using porous

alumina to hold potassium permanganate are being used to remove or chemically change gaseous pollutants in buildings. These devices are

incorporated into the heating, ventilating, and air conditioning systems,

similar to filters used to remove particulates. Particulate filters for

buildings can be evaluated using ASHRAE Standard 52-76, "Method of Testing

Air-Cleaning Devices Used in General Ventilation for Removing Particulate

Matter." Over the years, attempts have been made to evaluate gas removal

devices for some specific applications: however, no general methods exist

for testing and evaluating these devices. Such methods are needed so effective and economical control methods can be promoted fairly in the

marketplace for improved indoor air quality.

Technical Approach : Methods will be developed to evaluate the

effectiveness of devices for removing gaseous pollutants from air streams.

These methods will employ a test duct system in which a sample

7 5
filter/device is challenged with several gaseous pollutants introduced into

the intake air. The gaseous pollutants will be selected according to their

odors and possible adverse health effects, and presence in the indoor air.

The methods will include techniques for safely introducing metered amounts

of pollutants into the intake air of the test duct system and measurement

techniques using spectroscopy for determining the concentration of the

gaseous pollutants in the intake and outlet air of the test duct system.

The gaseous pollutant removal efficiency of the device can then be

calculated from the measured data.

The methods will also include ways to measure the capacity of such filters,

since their performance is affected by contaminants loading. It will then

be possible to combine the removal efficiency of a device with its

contaminant load so as to provide information for comparison between

filters and to estimate systems effectiveness and economic analysis of

various alternatives.

During this work, close cooperation will be maintained with the ASHRAE

technical committees on gaseous contaminants and removal equipment. It is

expected that ASHRAE would use the results of the study as a basis for a

consensus standard for evaluating devices used in ventilating systems for

buildings

.

Products Expected : Reports submitted to ASHRAE for voluntary standard

development

.

3. Title : Biochemical Formaldehyde Monitoring

Funding Proposed : $100K per year for two years

Ob i ec t i v e : The purpose of this project is to develop an inexpensive,

76
sensitive, reliable, easy-to-use, biochemical method specific for measuring

formaldehyde

.

Problem Significance : Formaldehyde is a nearly ubiquitous toxic gas that

is carcinogenic in laboratory animals. There have been many reports of

symptoms due to formaldehyde in mobile homes where formaldehyde emitting

materials are used, and in homes insulated with urea-formaldehyde foam.

Present measurement techniques for formaldehyde are either expensive,

subject to interference by other aldehydes, or not sensitive enough to

detect low airborne concentrations. Table 1 shows the sensitivity of

several of these methods. Bubbling air through water or aqueous sodium

bisulfite (NaHSO^) for 1 hour is required to collect enough formaldehyde

for detection by current analytical methods. Passive collections by solid

supports require even longer times.

Table 1. Formaldehyde Monitoring Methods

Sensitivity for

Sensitivity for Airborne Formaldehyde

Method Aqueous Formaldehyde (based on 60-min sample)

Chromotrop ic 0.25 u g/ml 0.1 ppm

acid

Pararosaniline 0.1 ug/ml 0.04 ppm

MBTH (for total 0.3 y g/ml 0.015 ppm

aldehydes)

Technical Approach : We proposed a method using a bacterial light-emitting

enzyme system that may be capable of measuring concentrations in the range

of pg/ml, which is about 10^ times as sensitive as the methods shown in

Table 1. The .method may also lend itself to continuous monitoring of

formaldehyde.

77
The enzyme formaldehyde dehydrogenase, which is isolated from yeast,

specifically oxidizes formaldehyde while at the same time reducing

nicotinamide adenine dinucleotide (NAD +

) to NADH. A highly sensitive

bacterial system is currently used to assay for NADH:

NADH + FMN + H

+ P^i-Aoxeduc t ase. —> uAD+ + FMNH2 FMNH2

+ 0

2 + long-chain aldehydes —

^erase, —> fmn + h^q + i ong chain

acid + hv (490 nm)

The system is extremely sensitive because of the ability of photometers to

detect small numbers of photons of light. Each photon corresponds to a

small number of molecules of NADH being oxidized. (Theoretically, each

molecule oxidized results in one photon, but some photons are absorbed by

the solution. The efficiency of photon transmittance is determined by

adding a known quantity of NADH to the solution after it has stopped

emitting photons.)

Bacterial luciferase is conveniently available, coated on the surface of

glass rods. Each rod may be used repeatedly hundreds of times by simply

dipping it into the solution to be tested and reading photon emittance in a

photometer

.

Products Expected : Reports on the method to sponsor.

4. Title : Standard Protocol for Field Measurement of Indoor Air Quality

Funding : $100K

Ob i ec t iv

e

: The purpose of this research is to establish a standard

protocol for measuring the indoor air quality which would allow a

meaningful comparison of collected data on indoor air quality in buildings.

Problem Significance : Indoor air quality measurements are affected by many

factors: weather, envelope tightness, building operation, building

78
occupancy patterns, design of the ventilation system, for example.

To date there is no standard procedure for collecting indoor air quality

information which would allow for 1) an assessment of the accuracy of the

data, 2) an assessment of the interpretation of the data and 3) the

meaningfulness of an extrapolation of the data to other situations and for

risk analysis. At present most data sets on indoor air quality are

incomplete, lacking measurements of all important environmental parameters,

complete descriptions of the buildings tested, measurements of the building

air leakage and ventilation rates, descriptions of the test methods used,

calibration or accuracy assessment of the instruments used, the sampling

methods used etc. The National Bureau of Standard has extensive experience

in the field monitoring of the environmental and energy performance of

buildings and has produced assessments of the field methods for assessing

the energy performance of buildings and its mechanical systems. Such field

measurement procedures should be extended to include the measurement of

indoor air quality.

Technical Approach : The National Bureau of Standards will develop a series

of standard protocols for the field measurement of indoor air quality on

commercial and residential buildings. Protocols will be established for

each of the major classes of contaminants found in residential and

commercial buildings (radon, formaldehyde and other organic compounds,

combustion products such as CO, CO 2 , NO, NO 2 , N0 X

, and particulates, and

asbestos). These protocols will contain 1) a procedure for characterizing

the building, its mechanical system, its usage and operation and reporting

of occupant complaints and problems, 2) environment parameter which should

be measured, 3) specific building tests which should be performed such as a

79
measurement of the air tightness of the building, its air infiltration

rate, and ventilation rate, 4) procedures used for measuring the various

contaminants, 5) recommended sampling methods, 6) statistical treatment of

the data, 7) a description of the equipment used and its required

calibration, and 8) an assessment of the accuracy of the data.

Products Expected : Reports on suggested protocols.

5. Title.: Methods for Measuring Ventilation Effectiveness

Funding Proposed : $100K first year, $150K second year

Ob iective : Study the mixing of ventilation air in the heated and airconditioned spaces by experimental measurement and to arrive at a

recommended procedure for determining the ventilation efficiency in

commercial and institutional buildings.

Problem Significance : Although the criteria for mechanical ventilation is

well established in terms of required outdoor air per occupant or per unit

of occupied space, all existing criteria assume perfect mixing between the

supply air and room air. All the recommendations are based on the

assumption that concentration levels of the contaminant in the return air

from the air conditioned and/or heated space are equal to the space average

concentrations. In other words, the current ventilation design is based on

100% ventilation efficiency. This assumption, although extremely

simplistic, has seemed to be adequate for most of the conventional

buildings, which are quite leaky and over-ventilated using constant air

volume systems. The combination of variable volume air systems and energy

conservation practices to reduce air infiltration, create entirely

different conditions. Variable air volume air supply systems (VAV) are

designed to regulate the total supply air flow rate to the space by the

space thermostat. The reduction of the supply air flow, however, is

80
restricted so that it still maintains minimum outside air flow

corresponding to the ventilation requirement. During periods of low

heating or cooling demand, the supply air flow rate is so drastically

reduced that it may not reach all the occupied zones in office buildings.

The supply and return air grills are usually in the ceiling and sometimes

located side by side in many of the modern office buildings. When the room

heating and cooling requirements are low, the reduced air results in such a

low outlet velocity at the supply air diffuser that it's throw is not

enough to reach the occupied zone.

It should be noted that it is also possible to have the opposite of the

above occur: that the effective ventilation rate of the occupied zone can

be greater than the average ventilation rate induced by the building air

handling systems. This will occur when part of the ventilation return is

located near localized contaminant sources.

There is little data on the actual ventilation efficiency of modern HVAC

systems. Data which do exist have been obtained in small structures and in

laboratory environments. In addition, several different definitions of

ventilation efficiency have been proposed and studied. At present there is

no accepted method for determining the effective ventilation rate of actual

buildings

.

Technical Approach : A method will be developed for measuring the

parameters required for determining the ventilation effectiveness in a general office building in which the source of air is through the

mechanical ventilation system, adjacent zones of the building and air

leakage through the building envelope. It is proposed to use a multi81
tracer gas technique for determining the various air flows in an occupied

zone of an office building. The office environment which will be tested

will be divided into two zones - one through which the ventilation enters

and the other the occupied zone. The rest of the building will be

considered as a single zone. A different tracer will be injected into each

zone and the level of all the tracer concentrations will be measured in all

zones. Such a measurement technique would permit the determination of 1)

the total amount of outside air entering each zone, 2) the flow of air into

and out of the occupied zone and the ventilation zone and 3) the amount of

air exchange between the test zone and the rest of the building. Though

such a method appears technically complicated, the recent development of

capillary absorption tubes for perf luorocarbon tracers makes such a

measurement scheme extremely practical, potentially simple and inexpensive,

if the tubes prove to be practical. It is proposed to develop this

measurement method for ventilation effectiveness, demonstrate its practical

* application to typical office buildings and develop a draft standard

practice or protocol for its use.

Products Expected : Reports on results as appropriate.

6. Title : Determining the Effects of Efficient Furnaces, Boilers, and

Water Heaters on Indoor Air Quality

Funding Proposed : $100K

Description : Retrofitting existing furnaces, boilers and water heaters to

make them more energy-efficient, or replacing these appliances can save

large amounts of energy. Many of these measures decrease the air

infiltration rate because less makeup air is required to satisfy the

reduced amount of fuel combustion made possible. Flue gas restrictors

reduce the exit of combustion gases. Heat reclaimers lower the temperature

82
of flue gases, creating the need for fans to exhaust combustion gases. The

effect of these measures may be to impair indoor air quality.

Concentration changes of such combustion gases as carbon monoxide and

nitrogen oxides will be determined before and after energy-efficient

changes are made to appliances.

7. Title : Feasibility of Monitoring Indoor Air for Pathogenic Bacteria

and Viruses by Serological Methods

Funding Proposed : $100K (Phase I)

Description : In the first phase, particles will be collected by standard

methods; for example, cyclones. Particles will be extracted and the

extract screened with sera or with synthetic monoclonal antibodies specific

against a battery of pathogenic organisms. This type of testing is

inexpensive, rapid, and does not require viable organisms or complex growth

regimes. The need to incubate organisms may have contributed in the past

to the difficulty of screening for viruses and many bacteria. If the first

phase is successful, methods may be refined to characterize pathogenic

microorganisms by particle size.

8. Title : Pollution Removal in Spaces by Natural Means

Funding Proposed : $100K

Description : Pollutant absorption on inside surfaces of building materials

and furnishings is an important mechanism impacting indoor air quality.

Studies using a few important contaminants will be made to investigate

removal methods and to develop models.

83
FORM NBS-1 14A I REV 11-841

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET (See instruction s)

1. PUBLICATION OR 2. Performing Organ. Report No. 3. Publication Date REPORT NO. 86-3305 JANUARY 1986

4. TITLE AND SUBTITLE

Rationale and Plan for Center for Building Technology

Research to Improve Indoor Air Quality

5. AUTHOR(S)

P. E. McNall

6. PERFORMING ORGANIZATION (If joint or other than N 8 S, see in struction s)

NATIONAL BUREAU OF STANDARDS

U.S. DEPARTMENT OF COMMERCE

GAITHERSBURG, MO 20899

7. Contract/Grant No.

8. Type of Report ^Period Covered

9.

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State, ZIP)

NBS

10.

SUPPLEMENTARY NOTES

Document describes a computer program; SF-185, FlPS Software Summary, is attached.

11.

ABSTRACT (A 200-word or less factual summary of most si gnificant in formation. If document includes a significant

bi bliography or literature survey, mention it here) This report outlines a suggested five year research plan for the Center for

Building Technology (CBT) in support of resolving the emerging indoor air

quality problem. The problem is defined, and the past research is summarized.

The important Federal responsibilities are identified. NBS contributions and

capabilities are noted. Future research needs are covered, and these form

the basis for the CBT research plan, in cooperation with other Federal agencies,

state and local governments, and the private sector.

12.

KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s) chemical measurements; engineering; indoor air quality;

models; physical measurements; research plan

13. availability

Uni i mi ted

|

j For Official Distribution. Oo Not Release to NTIS —

Order From Suoermtendent of Documents, U.S. Government Printing Office, Washington, DC

20402.

1 Order From National Technical Information Service (NTIS), Springfield, VA 22161

14. NO. OF

PRINTED PAGES

88

15. Price

$9.95

USCOMM-OC 85 «004