EVALUATING THE CONTRIBUTION OF UF-BONDED BUILDING MATERIALS

TO INDOOR FORMALDEHYDE LEVELS IN A NEWLY

CONSTRUCTED HOUSE

Daniel A. Hare

Technical Director

National Particleboard Association

18928 Premiere Court

Gaithersburg, MD 20879

William J. Groah

Technical Director

Hardwood Plywood and Veneer Association

1825 Michael Faraday Drive

Reston, VA 22090

L. Gregory Schweer

Director

Exposure/Risk Assessment Division

Versar, Inc.

P.O. Box 1549

Springfield, Virginia 22151

Richard L. Margosian

Executive Vice President

National Particleboard Association

18928 Premiere Court

Gaithersburg, MD 20879

Sidney W. Abel III

Environmental Scientist

U.S. Environmental Protection Agency

401 M Street SW

Washington, D.C. 20460

Michael D. Koontz

Senior Research Scientist and Manager

Indoor Air and Exposure Program

GEOMET Technologies, Inc.

20251 Century Boulevard

Germantown, Maryland 20878

April 17, 1996

Presented at

Washington State University

30th Annual Particleboard / Composite Materials Syposium

Pullman, Washington
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EVALUATING THE CONTRIBUTION OF UF-BONDED BUILDING MATERIALS TO

INDOOR FORMALDEHYDE LEVELS IN A NEWLY CONSTRUCTED HOUSE

ABSTRACT

 A Pilot Study to evaluate methods for measuring the contribution of UF-bonded building

materials to indoor formaldehyde concentrations in newly constructed conventional and

manufactured houses was recently conducted by the U. S. Environmental Protection Agency

(EPA). The Pilot Study was funded by the National Particleboard Association (NPA); and was

conducted under a Cooperative Research and Development Agreement (CRDA) between the two

organizations. The Pilot Study followed scientifically designed protocols and evaluated indoor

formaldehyde concentrations in a newly constructed, conventionally built, single-family house

that contained two different combinations of UF- bonded building materials with known emission

characteristics. Higher than expected expenditures in the conventional house resulted in the

cancellation of the manufactured housing portion of the Pilot Study. The UF-bonded building

materials used in the Pilot Study were fully characterized; environmental conditions in the house

were carefully controlled and recorded; and indoor concentrations were measured on a regular

basis.
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Results of the Pilot Study show that initial indoor formaldehyde concentrations in the house,

even at a “High” loading of UF-bonded building materials, were below 0.076 parts per million and

were as much as 50 percent below the levels that had been predicted by commonly used indoor

air models. After 30 days, average indoor formaldehyde concentrations in the house were less

than 0.045 parts per million.

The Pilot Study pointed out significant technical and logistical problems inherent in studies of

this type. House availability, control of test conditions, budgeting, scheduling, measurement

techniques, and other issues posed challenges to all involved. Researchers eventually were able to

resolve most of these problems in a satisfactory manner. However, these challenges may

proliferate in a wider study of this type, or in one involving a greater number of houses in

multiple locations.

INTRODUCTION

 On September 29, 1994, the National Particleboard Association (NPA) signed a Cooperative

Research and Development Agreement (CRDA) with the U.S. Environmental Protection Agency

(EPA) to fund a Pilot Study in newly constructed conventional and manufactured houses. The

purpose of the Pilot Study was to evaluate methods used to measure the contribution of UFbonded building materials to indoor formaldehyde concentrations in newly constructed

conventional and manufactured houses.

 The Pilot Study is noteworthy in several respects. First, this carefully controlled and

scientifically designed protocol provided for a more comprehensive investigation and better
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documentation of results than most prior studies of formaldehyde levels in houses. The specific

products used in the Pilot Study were fully characterized; conditions in the house were charted;

and the resulting ambient levels were measured consistently. The levels reported for all product

loading scenarios were below 0.1 ppm and were up to 50 percent below the levels that had been

predicted by commonly used indoor air models.

 Second, the Pilot Study helped to identify the significant technical and logistical problems

inherent in studies of this type. House availability, control of test conditions, budgetary

projections, scheduling, difficulties with measurement techniques, and other issues posed

challenges to all involved. Eventually, most of these were satisfactorily resolved in the context of

a single-family conventional house, but the challenges may proliferate in a wider study of this

type, or in one involving a large number of houses in multiple locations. Although the project

plan called for testing to be conducted in both conventionally built and manufactured houses,

higher than expected expenditures encountered in the conventional house affected the budget and

forced a decision in July 1995 to scale back testing in the conventional house and to cancel testing

in the manufactured houses.

 The Pilot Study was also noteworthy as an example of scientific cooperation among the EPA,

its contractors and the industries involved. Although there were, and continue to be, some

disagreements regarding the subject of formaldehyde, the work is a tribute to the professionalism

and insight of the experts at Versar, Inc., GEOMET Technologies, Inc., and Battelle who

participated in the design of the Pilot Study and conducted the testing, the professional staff of

EPA’s Office of Pollution Prevention and Toxics, and the Industry Advisory Panel.
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HISTORY OF EPA PILOT STUDY

 In December 1992, the EPA placed a notice in the Federal Register announcing the need to

conduct a Formaldehyde Exposure Assessment Study in new houses to determine whether

formaldehyde emissions from UF-bonded pressed wood products were sufficiently high to cause

health concerns. At a public meeting in January 1993, EPA representatives outlined a proposed

study plan that had been developed by EPA with support from Battelle of Columbus, Ohio. The

proposed study would be conducted in two phases - a main study and a pilot study. The

proposed main study would have involved exposure testing using passive monitors in 108 newly

constructed conventional and manufactured houses located throughout the United States. A

smaller pilot study would have been conducted first to evaluate the feasibility and logistical

considerations of the experimental design for the larger main study.

 Throughout early 1993, NPA and EPA discussed the need for such testing and the

appropriate scope and design of a Pilot Study. The Agency initially proposed a broader, survey

type study. NPA proposed that smaller, more focused, and more controlled studies were more

appropriate. In September 1993, a compromise was reached. NPA agreed to fund a Pilot Study

in a single conventionally built newly constructed house and in four (4) newly constructed

manufactured houses. NPA’s commitment was for the Pilot Study only.

 A letter of intent to conduct the Pilot Study was signed by both parties in December 1993 and

a formal Cooperative Research and Development Agreement (CRDA) was finalized in September

1994. Under the terms of the Cooperative Agreement:

EPA would:

• be responsible for the overall management of the study,
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• provide funding to develop the Quality Assurance Project Plan (QAPP), and

• provide limited quality control checks by performing independent formaldehyde

emissions tests on trim materials, on carpet/padding, and on other non-wood materials

used in the houses.

NPA and industry would provide:

• $460,000 in direct funding,

• materials for the study, such as

particleboard underlayment and industrial board for countertops,

hardwood plywood wall paneling,

kitchen cabinets and bathroom vanities,

cabinet and vanity countertops,

interior doors, and

• wood product emission testing (large and small chamber),

• access to manufactured houses, and

• 1.5 person years of technical and administrative assistance.

 EPA had contracted with Versar, Inc. of Springfield, Virginia, to manage the Pilot Study. Field

and laboratory testing would be conducted by a subsidiary of Versar Inc., GEOMET

Technologies, Inc. of Germantown, Maryland.

 An Industry Advisory Panel comprised of technical representatives from the particleboard,

hardwood plywood, kitchen cabinet, and manufactured housing industries met with EPA
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personnel to discuss the logistical and technical aspects of conducting the EPA designed Pilot

Study. Technical issues addressed included:

• types of houses to be included in the study,

• products to be included in the study,

• emission characteristics of those products,

• combinations of products to be installed in the house,

• environmental conditions (temperature, relative humidity, ventilation rate) in the

houses, and

• the method of determining indoor concentration levels in the houses.

 The joint EPA-Industry Technical Advisory Team identified the experimental variables that

would be included in the Pilot Study and defined low, medium, and high categories for each

variable.

QUALITY ASSURANCE PROJECT PLAN (QAPP)

 In October 1994, the Quality Assurance Project Plan (QAPP) for the Pilot Study was

finalized by GEOMET. The QAPP is over 100 pages long and gives a detailed description of the

experimental design, experimental variables, and quality assurance/control procedures that would

be employed.
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 The objectives of the Pilot Study were to:

• Test the logistical considerations relevant to carrying out the experimental procedures of

the testing program in a single conventionally-built single-family house and in multiple

manufactured houses.

• Demonstrate that the experimental variables or conditions likely to affect formaldehyde

concentrations in new houses (namely, UF-bonded wood product emission

characteristics, UF-bonded wood product loading rates, temperatures and indoor air

exchange rates) can be controlled, individually and jointly varied, and held sufficiently

constant, and that the response can be measured to a specified precision.

• Demonstrate that test results can be obtained across a range of different experimental

conditions similar to that which can be present in new houses and that the response can

be measured with specified precision.

• Estimate the extent of variability of the experimental results and the variation with

changes in experimental conditions.

• Determine how to account for, or to eliminate or minimize, residual formaldehyde

carryover between test runs in the conventional house due to the effects of inherent sinks.

• Evaluate the ability to control and vary the air exchange rate of houses using an adjustable

mechanical air handling system.

 According to the QAPP, the Pilot Study would include one (1) unoccupied, conventionally

built single-family house and four (4) unoccupied manufactured houses. Four manufactured

houses were specified in the Pilot Study because it is not practical to install and remove products
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in a manufactured house. The conventional house was to be a two-story house on a slab or

crawlspace.

 The QAPP also specified that the following variables would be evaluated in the Pilot Study:

• Product emission characteristics: Only “medium” emitting products would be used in the

Pilot Study. Emissions from particleboard and plywood wall paneling (as measured by

ASTM E 1333) would be between 0.12 and 0.14 ppm. Since there were no established

protocols for measuring formaldehyde emissions from kitchen and bathroom cabinets,

commercially available cabinets constructed with “medium” emitting materials (melamine

wrapped particleboard) would be used.

• Product loading rate: Two combinations of products, Medium and High (defined below)

would be installed in the house:

Material High Medium

PB Underlayment Full (0.10)1 Half

Cabinets Full Full

Counter Tops Full Full

Interior Doors Full Full

Plywood Wall Paneling Full (0.02-0.036)1 None

1

 Approximate loading rate in ft2/ft3

• Environmental conditions in the house:

Temperature 75 oF

Ventilation rate 0.5 ACH
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Relative humidity level in the house, while not a controlled variable, would be targeted at 50

percent.

Conventional House Preparation and Testing

 Since the manufactured houses were eventually dropped from the Pilot Study, the following

discussion of the QAPP provisions will pertain solely to the conventional house.

 Air leakage - Air leakage in the house would be determined through blower-door tests

conducted in accordance with ASTM E 779. Every effort would be made to make the house as

tight as possible.

 Ventilation rate - Ventilation rates would be controlled by a mechanical heat recovery

ventilator (HRV) attached to the heating and air conditioning system (HAC). Air exchange rates

would be measured by using two tracer gas methods - Perfluorocarbon tracers (PFT’s) and sulfur

hexafluoride (SF6 ).

 Product loading - Four product loadings would occur - two Medium and two High. Prior to

loading the products in the house, a baseline value for the house without any experimental UFbonded wood products in it would be determined. The products would then be installed in the

house and indoor formaldehyde concentration measurements would be taken over approximately

a 30-day period. At the completion of 30-day period, the products would be removed from the

house. The house would be allowed to “air out” for several days until a new equilibrium level

(baseline) was reached, then the next set of products would be installed. The order of the loading

configurations in the house would be randomized, with the single constraint that loadings 1 and 2

would be different (i.e. one High, one Medium).
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 All of the products in the house would be installed according to manufacturers’ recommended

installation instructions.

 Indoor formaldehyde measurements - Indoor formaldehyde concentration levels would be

tested 7, 12, 28, and 33 days after the products were installed in the house. If necessary,

additional testing could take place to confirm any trends or unexpected results. Day 12 and 33

readings would be considered statistical replicates of Day 7 and 28 readings, respectively.

 Twenty-four (24) hour time-integrated formaldehyde measurements in the house would be

determined by the following methods:

• EPA Method IP-6A - Solid Adsorbent Cartridge (DNPH)

• NISOH Method 3500 - Chromotropic Acid (CA)

 Indoor formaldehyde concentrations would be measured by both methods at several locations

in the house. Measurements would be taken in the kitchen, living room, upstairs bedroom,

basement, and outdoors. A duplicate sample would also be collected each time at a location to be

systematically varied.

 An Interscan Model 1160 electro-chemical continuous formaldehyde analyzer would be used

to measure formaldehyde levels in the living room.

 Although not a provision of the QAPP, industry would conduct one-hour random “shadow

tests” in the house using the NIOSH 3500 chromotropic acid procedure.

Laboratory Testing

 Emission characteristics of UF bonded building materials - Product emission testing would be

conducted by industry at three different air exchange rates according to the protocol in ASTM E
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1333 (Large Chamber Test Method). Since there are no established protocols for large chamber

testing of doors and cabinets, the following loading rates would be used:

• Doors - five doors at a total loading rate of 0.125 ft2/ft3

• Kitchen cabinets/countertops - one base and one wall cabinet with doors closed at a

loading rate of 0.133 ft2/ft3. A section of countertop would be placed on the base cabinet

during testing.

The above loading rates are similar to those established by the Department of Housing and Urban

Development (HUD) for large chamber testing of particleboard and industrial panels.

 Sink effect testing of painted gypsum wallboard and carpet/padding - For sink effect testing,

products would be placed in a small clean environmental chamber. A known concentration of

formaldehyde gas would be injected into the chamber. By accurately measuring concentrations in

the small environmental chamber, it could be determined whether the material was absorbing the

formaldehyde gas and then re-emitting it after the source was removed.

BUILDER RECRUITMENT

 During the summer and fall of 1994, Versar personnel initiated efforts to recruit a builder or

homeowner who would be willing to participate in the Pilot Study. Numerous contractors were

contacted and ads were placed in local papers. Securing a contractor willing to participate in the

Pilot Study proved to be more difficult and costly than anticipated for a variety of reasons. The

primary reason given for not participating in the Pilot Study was the fact that the house could

not be occupied during the test period. Most contractors or new homeowners wanted to occupy,

or at least have access, to the house. After expanding the search geographically, a homeowner in
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Centreville, Maryland, agreed to participate in the Pilot Study. Centreville is on the eastern

shore of Maryland and is approximately 90 miles from Germantown, Maryland, the location of

the offices of the testing contractor, GEOMET Technologies, Inc. The owner was building a

rental house and was willing to lease it for as long as necessary. The required paperwork was

signed in October 1994, and GEOMET personnel started to prepare the nearly completed house

for testing.

CONVENTIONAL HOUSE DESCRIPTION

 The Centreville, Maryland, house was a conventionally built, 1326 ft2, two-story Cape Cod

style house with a full basement. Total volume of the finished living space was 10,746 ft3 (304

m3 ). The QAPP had called for a house with a crawl space, but efforts to find such a house in the

Washington D.C., area were unsuccessful. The first floor of the house was 712 ft2 and had 5931

ft3 (168 m3) of living space that consisted of a living room, kitchen, bathroom/laundry room, and

bedroom. The second floor of the house was 614 ft2 and had 4815 ft3 (136 m3) of living space

that consisted of two bedrooms and a bathroom. The door from the first floor finished living

space to the unfinished basement was sealed shut during the entire project. The house was

unoccupied and contained no furniture or draperies. A floor plan of the house and a picture of the

exterior of the house are shown in Figure 1.

PRODUCTS USED IN CONVENTIONAL HOUSE

 Under the terms of the CRDA, industry was responsible for procuring the products that

would be used in the Pilot Study. Sufficient quantities of 5/8” particleboard underlayment, 3/4”
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industrial particleboard for countertops, 1/4” hardwood plywood wall paneling (3-ply birch face,

tropical hardwood back and core with 7 cut grooves along the length of each panel to simulate

random width lumber planking), interior partition doors, and kitchen and bathroom cabinets were

obtained from member companies, participating associations, or purchased at local building

supply centers. Emission characteristics of the particleboard and plywood wall paneling used in

the Pilot Study were determined prior to selecting the materials for testing. Initial emission

characteristics of the products used in the Pilot Study (determined by ASTM E 1333 at 0.5

ACH) were determined and are listed below:

Test Loading

Product Emissions, ppm Rate, ft2/ft3

Particleboard Underlayment 0.144 0.130

Plywood Wall Paneling 0.114 0.290

Cabinets 0.053 0.133

Interior Doors 0.052 0.125

 All of the products were stored in a GEOMET controlled-access warehouse in Gaithersburg,

Maryland until they were installed in the house. During storage, products were wrapped in 6-mil

plastic to minimize any formaldehyde off-gassing. It was discovered during the Pilot Study that

temperature control in the warehouse was marginal and that temperatures ranged up to 85 oF.

 Products were installed in the house according to manufacturers’ recommended installation

instructions, and conventional practices were followed. The particleboard underlayment was

installed with screws for easy removal. The kitchen and bath cabinets were screwed tightly
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against the wall. The plywood wall paneling was nailed to the wall in order to minimize any

damage to the gypsum wallboard.

 For the Medium loading scenario, particleboard underlayment was installed on the first floor

of the house. Interior doors and a full set of kitchen and bathroom cabinets and countertops were

installed. For the High loading scenario, particleboard underlayment was installed on both the

first and second floors of the house. In addition, twelve 4’ X 8’ sheets of plywood wall paneling

were installed in the house. In order to establish a somewhat uniform loading and to avoid using

partial panels, four full size sheets were installed in an upstairs bedroom, in the downstairs

bedroom, and in the living room. Interior doors and a full set of kitchen and bathroom cabinets

and countertops (same number as for Medium loading) were also installed. Table 1 lists the

square footage of each product type that was installed in the house during the Medium and High

loadings. Particleboard underlayment was not installed in the kitchen and bathroom areas of the

house. Those areas were covered by vinyl sheet goods which had been permanently installed

during final preparation of the house before field testing was initiated.
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INSERT TABLE 1 HERE

The location of products in the house for the High loading scenario is shown in Figure 2.

TESTING IN CONVENTIONAL HOUSE

 Preparing the house for testing took longer than anticipated. Blower door tests conducted in

December 1994 indicated that the house had numerous leaks in the building shell and between the

first floor and basement. Air leakage sites were identified (service penetrations between the

basement and first floor and along the baseplate) and sealed with caulk and foam. Numerous

leaks were also found in the forced-air HAC distribution system. Sealing the leaks helped reduce

the leakage in the house to a natural air change rate of 0.2 per hour. In January 1995, the heat

recovery ventilator was installed. During this time, laboratory equipment for measuring

formaldehyde concentrations in the house and a computer data acquisition system (DAS) were

installed. The DAS would provide a continuous record of temperature, humidity, and solar

radiation as well as control the SF6 tracer gas ventilation measurements and Interscan real-time

formaldehyde analyzer.

 Baseline testing took place in March 1995. Load 1 (Medium) products were installed in

April, and indoor concentration levels were measured following the protocols outlined in the

QAPP. In late May, it became evident that the contractor was having problems controlling

relative humidity levels in the house. While targeted at 50 percent, humidity levels in the house

reached over 70 percent in late June. Additional dehumidification equipment was installed in the

house, and humidity levels dropped down to the desired range. Since high humidity causes higher
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formaldehyde emissions, the house was declared to be in an “upset condition” during this time.

The EPA decided that Load 1 products should be left in the house until conditions stabilized.

The final reading for Load 1 (Day 78) was taken in late July. Results from Load 1 testing are

shown in Table 2 and Figure 3.

INSERT TABLE 2 HERE

REVISED PROJECT PLAN

 In late May, while Load 1 products were still in the house, the EPA advised NPA that

they were encountering financial problems with the Pilot Study and estimated that it

would cost more than originally estimated to complete the Pilot Study as outlined in the

CRDA. In July, the joint EPA-Industry Technical Advisory Team met to review the

status of the project. Given the new financial constraints, the Study Plan was modified

with the following changes:

• Conducting only three (3) loadings in the house. If sufficient financial resources became

available, a fourth loading (Medium - repeat of Load 1) would be conducted,

• Using only DNPH testing,

• Deferring some of the laboratory sink effect and barrier testing,

• Fixing the air-out period between loads at seven (7) days instead of waiting for

formaldehyde levels in the house to come to equilibrium, and

• Deleting the manufactured house portion of the Study.

LOAD 2 AND 3 TESTING IN THE CONVENTIONAL HOUSE
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 Load 1 products were removed from the house in late July 1995. The house was allowed to

air out for 7 days, and Load 2 (High) products were installed. Formaldehyde concentrations were

measured on Days 7, 12, 28, and 33. Load 2 test results are shown in Table 3 and Figure 4.

INSERT TABLE 3 HERE

 Load 2 products were removed from the house in late September 1995. Load 3 (High -

duplicate of Load 2) products were installed in early October 1995 after the house had been

allowed to air out for 7 days. Formaldehyde concentrations were measured on Days 7, 12, 28,

and 33. Load 3 products were removed from the house in early November 1995, and the house

was returned to the homeowner. Load 3 test results are shown in Table 4 and Figure 5.

INSERT TABLE 4 HERE

ADDITIONAL INDUSTRY FUNDED LABORATORY TESTING

 As a result of the budgetary constraints, only a limited amount of sink effect testing was

conducted as part of the Pilot Study. After reviewing the laboratory sink effect test results and

results from Loads 1, 2, and 3, it appeared that the gypsum wall board was acting as a significant

sink. EPA modelers felt that the sink characteristics of the painted gypsum wallboard, since the

exposed surface area was greater than all of the UF-bonded products installed in the house, would

be very important in their efforts to verify existing indoor air models. The modelers indicated

that additional information was needed to characterize fully the sink effect behavior of the

painted gypsum wallboard. It was also suggested that it would be important to determine
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whether the carpet/padding used in the house was acting as a sink or had any barrier effect on

formaldehyde emissions from the particleboard underlayment. In an effort to provide insights on

possible sink and barrier effects, NPA contracted with GEOMET in December 1995 to conduct:

• Additional sink effect testing on the painted gypsum wallboard and carpet/padding used in

the house, and

• Barrier testing on the carpet/padding used in the house.

For barrier testing, it was originally proposed that a conventional “break through” testing

protocol be followed. GEOMET personnel suggested that an alternative protocol be followed in

order to evaluate the floor system with particleboard underlayment and carpet/padding instead of

just the carpet/padding. A sample of particleboard underlayment would be placed in a stainless

steel pan and inserted in a small environmental chamber. Formaldehyde concentrations in the

environmental chamber would be determined using the Interscan analyzer. As a separate test, a

second sample of particleboard that had carpet/padding on top of it would be placed in a stainless

steel pan and inserted in the small environmental chamber. Again, formaldehyde concentrations

in the chamber would be measured. Differences in the concentration profiles for the two tests

would reflect the barrier effect of the carpet/padding used in the Pilot Study. To minimize the

inherent variability within a piece of particleboard, NPA would prescreen the particleboard

samples using a small chamber (Dynamic Microchamber). The two pieces that had the closest

emissions would be provided to GEOMET for the test.
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RESULTS

Conventional House Formaldehyde Testing

 Average formaldehyde concentrations in the house did not exceed 0.070 ppm, even during the

two High loadings. The highest individual value obtained in the house was 0.076 ppm and

occurred in the kitchen during Load 3 (High). The results clearly show that for all three loadings

indoor concentrations peaked before the 33-day measurements. After 30 days, average indoor

concentrations in the house were below 0.045 ppm. Average results for the house are shown in

Figure 6.

 These concentrations are below 0.1 ppm and are lower than concentrations predicted by

commonly used indoor air models. As expected, the two High loadings (Loads 2 and 3) resulted

in higher initial indoor concentrations than the Medium loading (Load 1), but all of the loadings

showed concentrations lower than predicted using indoor air models. Indoor concentrations for

the two High loads decreased slowly over time and appeared to reach the same equilibrium

concentration obtained with the Medium load (Load 1). Results show that there was fairly good

duplication between results for the two High loadings (Loads 2 and 3).

 NPA representatives conducted “shadow testing” on several occasions during each loading.

Results of this testing were similar to those obtained by GEOMET.

 Ventilation rate data indicated differences between the results obtained with the SF6 and PFT

tracer gas methods. Although the collective results were generally in the target range of 0.4 to 0.6

ACH, the PFT values were consistently higher. One possible reason for the discrepancy is the

inherent difference between the two measurement technologies. The SF6 method involves

periodic injection and mixing of the tracer through the HAC system, followed by real-time
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analysis of the concentration decline due to dilution by infiltrating outdoor air. The PFT method

relies on near-constant release of tracers from multiple locations near the perimeter of the house,

accompanied by time-integrated sampling over a 24-hour period.

 DNPH results were consistently lower than corresponding chromotropic acid results in Load

1. EPA contractors attributed this difference to difficulties encountered with processing the

samples during analysis; and claim that it is not a reflection of the accuracy of the chromotropic

acid method for formaldehyde measurements.

Laboratory Testing

 Materials - Emission characteristics of the UF bonded products used in the Pilot Study were

determined at three different ventilation rates when the products were removed from the

Gaithersburg warehouse for installation in the conventional house. While 0.15, 0.5, and 1.2 ACH

were designated in the QAPP, tests were actually conducted at 0.25, 0.5, and 1.0 ACH because

of chamber operating parameters. Results indicate that some decay may have occurred during

storage, even though the products were wrapped in plastic. The elevated temperatures in the

warehouse may have accelerated the decay process somewhat.

 Sink Effect - Laboratory testing indicated that the gypsum wallboard definitely acted as a

sink. Due to the large exposed surface area of painted gypsum wallboard in a conventional house

(walls, ceilings, etc.), the sink effect characteristics of the painted gypsum wallboard are an

important factor in indoor air quality modeling. Laboratory tests also indicated that the

carpet/padding used in the Pilot Study acted as a minor sink.
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 Barrier - Barrier testing in the small chamber indicated that the carpet/padding used in the Pilot

Study did not substantially inhibit or retard the movement of formaldehyde from the

particleboard underlayment.

 Other - Despite all of the efforts to isolate the basement from the rest of the house,

formaldehyde was detected in the basement during baseline testing and all 3 product loadings.

Possible sources of the formaldehyde include:

• Leakage from upstairs area

• Emissions from fiberglass insulation, plywood subfloor (ceiling in basement), or other

formaldehyde containing materials in the basement.

CONCLUSIONS

• Several major unanticipated logistical problems were encountered. Although these problems

were satisfactorily addressed, they highlight the difficulties inherent in these types of tests,

even with one, well-controlled facility.

• The highest average indoor formaldehyde concentration in the occupied areas of the house

was below 0.070 ppm.

• The highest indoor formaldehyde concentration in the occupied areas of the house was 0.076

ppm (occurred in kitchen during Load 3 (High).

• The lowest indoor formaldehyde concentration in the occupied areas of the house was 0.020

ppm (occurred in upstairs bedroom during Load 1 (Medium).

• After 30 days, average indoor formaldehyde concentrations in the house had decayed to less

than 0.045 ppm for all three loadings.
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• There was very good agreement between indoor formaldehyde concentrations in each room of

the house for all three loadings, and indicates that there was good mixing of air in the finished

areas of the house.

• The Pilot Study demonstrated that the following experimental variables could be controlled

within the targeted range:

• Product emission rates

• Loading rates in the house

• Indoor temperature

• Indoor ventilation rate

• Painted gypsum wallboard appeared to act as a significant sink.

• The continuous formaldehyde analyzer is not suitable for measuring low concentrations over

long periods of time, but it may be useful for chamber tests provided it is placed in a

temperature-controlled environment.

• The particular carpet and padding used in the house did not appreciably retard the rate of

formaldehyde emissions from the particleboard underlayment into the rest of the house.

• There was poor agreement between the PFT and SF6 tracer gas test methods used to measure

ventilation rates in the house.

• Baseline values for Load 2 and 3 were in close agreement and were higher than the Load 1

baseline values. This indicates that the gypsum wall board in the house may have been acting

as a reversible sink between Loads 2 and 3. The painted gypsum wallboard apparently

reached a near equilibrium value as there was little difference between baseline results for

Load 2 and 3.
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• Industry chromotropic acid shadow testing exhibited similar trends to EPA’s DNPH results.

SUCCESSES

 Despite the difficulties, there were a number of positive results demonstrated during the Pilot

Study:

• All of the parties involved in the project worked together in a cooperative spirit to obtain

as much technically sound data as possible.

• Building materials with appropriate emission characteristics could be readily obtained.

• Targeted temperature and air exchange rates in the house could be controlled with the heat

recovery ventilator.

• Results from the two High loading scenarios (Loads 2 and 3) were in close agreement.

• There was adequate mixing of air in the first and second floor living areas of the house.

PROBLEMS

 Some problems were encountered in the Pilot Study:

• Budgeting

• Underestimation of time and effort required to prepare and characterize the Centreville,

Maryland house

• Location of conventional house - a minimum of a full man-day was required any time a

technician visited the house to conduct testing or maintain/service the equipment

• Continuous monitor

• required weekly maintenance
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• experienced considerable drift

• Difficulties controlling humidity levels in the house

CURRENT STATUS

 A final report covering the Pilot Study was delivered to EPA and NPA in late March 1995.

The report is over 110 pages long and gives a detailed description of the experimental design,

testing in the conventional house and laboratory, and problems encountered. Copies of the

report are available from U.S. Environmental Protection Agency or the National Particleboard

Association.

REFERENCES

American Society for Testing and Materials. 1987. Standard Practice for Measuring Air Leakage

by the Fan Pressurization Method; Standard E 779-87; American Society for Testing and

Materials, West Conshohocken, PA.

American Society for Testing and Materials. 1990. Test Method for Determining Formaldehyde

Levels from Wood Products Under Defined Conditions Using a Large Chamber; Standard E

1333-90; American Society for Testing and Materials, West Conshohocken, PA.

GEOMET. 1994. Residential Indoor Air Formaldehyde Testing Program: Pilot Study Quality

Assurance Project Plan. Report No. IE-2695. GEOMET Technologies, Inc., Germantown,

MD.

GEOMET. 1996. Residential Indoor Air Formaldehyde Testing Program: Pilot Study Final

Report. Report No. IE-2814. GEOMET Technologies, Inc., Germantown, MD.

National Institute for Occupational Safety and Health. 1994. Chromotropic Acid Method for

Determination of Formaldehyde in Air; Method 3500, NIOSH Manual of Analytical Methods

(Fourth Edition), National Institute for Occupational Safety and Health, Cincinnati, OH.

U.S. Environmental Protection Agency. 1994. Cooperative Research and Development

Agreement (CRDA), Federal Technology Transfer Act (FTTA). Tracking # 103-94. Cooperative
25

agreement between the National Particleboard Association (NPA) and EPA (OPPT and ORD).
26

Table 1. Loading Areas for Underlayment, Paneling, Doors and Countertop

at the Conventional House

LOADING AREA - FT2

COMPONENT 1ST FLOOR 2ND FLOOR

MEDIUM

LOADING

HIGH

LOADING

MEDIUM

LOADING

HIGH

LOADING

UNDERLAYMENT 496.2 496.2 0 519.3

PANELING 0 256.0 0 128.0

DOORS 203.6 169.6

COUNTERTOP 37.9 5.65
27

Table 2.--Load 1 (medium) indoor formaldehyde concentrations, ppm

LOCATION BASELINERUN 1

DAY 7*

RUN 2

DAY 12*

RUN 3

DAY 28*

RUN 4

DAY 33*

RUN B

DAY 50*

RUN C

DAY 78*

LIVING ROOM 0.009 0.028 0.030 0.042 0.037 0.051 0.037

KITCHEN 0.010 0.030 0.031 0.044 0.039 0.047 0.038

BEDROOM 0.010 0.020 0.030 0.036 0.031 0.045 0.032

BASEMENT 0.090 NA 0.027 0.028 NA 0.023 0.030

AMBIENT 0.001 0.001 0.007 0.002 0.002 0.002 0.002

AVG. INDOOR

TEMP, °F

RH, %

72

50

74

42

74

45

75

62

75

50

77

67

74

57

* The number of days after products were installed in the house
28

Table 3.--Load 2 (high) indoor formaldehyde concentrations, ppm

LOCATION

BASELINERUN 1

DAY 7*

RUN 2

DAY 12*

RUN 3

DAY 28*

RUN 4

DAY 33*

LIVING ROOM 0.023 0.060 0.056 0.047 0.039

KITCHEN 0.024 0.061 0.058 0.049 0.041

BEDROOM 0.022 0.061 0.055 0.053 0.048

BASEMENT 0.026 0.040 0.040 0.038 0.031

AMBIENT 0.003 0.003 0.002 0.001 <0.001

AVG. INDOOR

TEMP, °F

RH, %

74

53

74

56

74

50

75

47

73

47

* The number of days after products were installed in the house.
29

Table 4.--Load 3 (high) indoor formaldehyde concentrations, ppm

LOCATION BASELINERUN 1

DAY 7*

RUN 2

DAY 12*

RUN 3

DAY 28*

RUN 4

DAY 33*

LIVING ROOM 0.026 0.072 0.054 0.043 0.042

KITCHEN 0.026 0.076 0.055 0.046 0.040

BEDROOM 0.028 0.066 0.055 0.040 0.044

BASEMENT 0.025 0.043 0.030 0.020 0.023

AMBIENT <0.001 <0.001 0.001 0.001 0.001

AVG. INDOOR

TEMP, °F

RH, %

73

50

73

64

72

48

75

43

71

46

* The number of days after products were installed in the house
30

FIGURE 3 – AVERAGE INDOOR FORMALDEHYDE CONCENTRATIONS, PPM, LOAD

1 (MEDIUM) – 24 HOUR DNPH RESULTS

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80

DAYS

INDOOR LEVELS, PPM

LIV RM

KITCH

BED RM
31

FIGURE 4 – AVERAGE INDOOR FORMALDEHYDE CONCENTRATIONS, PPM, LOAD

2 (HIGH) – 24 HOUR DNPH RESULTS

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34

DAYS

INDOOR LEVELS, PPM

LIV RM

KITCH

BED RM
32

FIGURE 5 – AVERAGE INDOOR FORMALDEHYDE CONCENTRATIONS, PPM, LOAD

3 (HIGH) – 24 HOUR DNPH RESULTS

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34

DAYS

INDOOR LEVELS, PPM

LIV RM

KITCH

BED RM
33

FIGURE 6 – AVERAGE INDOOR FORMALDEHYDE CONCENTRATIONS, PPM,

ALL 3 LOADS – 24 HOUR DNPH RESULTS

0.010

0.042

0.036

0.030

0.041

0.023 0.026

0.050 0.060

0.056

0.043

0.042

0.053

0.070

0.025

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

0.10

0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34

DAYS

INDOOR LEVELS, PPM

LOAD 1

LOAD 2

LOAD 3