1. Model-based Characterization of Indoor Gaseous Emissions EPA03 T1.A, 1.B and EPA04 T1.2
Jensen Zhang, John Grunewald,
Jim Smith, Hui Li, Jing Xu, and Beverly Guo
Syracuse University

2. The Problem and Research Needs
Material Emissions and IAQ
ASHRAE Standard Ventilation for Acceptable IAQ
CIB Performance Criteria of Buildings for Health and Comfort
Green Building Products
Harmonized test method
Simplified, fast and less expensive screening/rating method
Long-term emission characteristics under usage conditions
Source-Sink Interactions
Large number of sources/sinks and pollutants
Primary and secondary emissions
Short and long-term exposure
Understanding of Emission/Sorption and Transport Processes
Composite materials
Multilayer material assemblies
Correlations with VOC properties
Effects of environmental conditions
O3 initiated VOC and particle emissions

3. Research Objectives The Ultimate Goal:
Reliable and practical integrated testing and modeling methodology
Practical methods for rating products, and long-term exposure predictions
Specific Objectives for EPA03/04 Project (5 years):
Mechanistic emission and transport model
CHAMPS-BES (EPA03/04)
Test methods for model parameters
VOC extraction method (EPA03/04)
Dual-chamber test method (EPA03/04)
Application & demonstration
Simplified standard test methods (EPA03/04)
Fast screening
Product certification (BIFMA M7.1)
Exposure assessment (EPA04)

4. What is a Model-based Testing & Evaluations?
Conventional test methodology
Model-based test methodology
Standard
Testing
Concentration
over time
C=f(t)
Data
analysis
procedure
Short-term
emission
factors
Material
Comparison
& rating
Impact
on IAQ ?
Field-condition
Performance
Product
Comparison
& rating
Standard
Testing
Model
parameters
Mechanistic
model for
predictions
Impact
on IAQ
& Energy

5. Model-based Testing and Evaluations
An example for multi-layer systems…
Testing for individual layers
Performance evaluation
Modeling
Measuring initial concentrations &
partition coefficients
Chamber A
Chamber B
RH/T Sensor
Pressure sensor
Simplified model for
conventional
test method
CHAMPS user interface
Gypsum
Board
Measuring diffusion coefficients

6. Development of mechanistic model and test methods
Roadmap
EPA03
EPA04
2004
2005
2006
2007
2008
Development of mechanistic model and test methods
CHAMPS-BES 1.0
Dual-chamber
New emphases:
office furniture
indoor materials
VOC extraction
Delphin 4
(TUD, 7+ years)
BIFMA M7.1
VOCs - water vapor similarity
Database of model parameters
Fast screening method
Impact on exposure

7. In response to the SAC06 Review
SAC comments
Too much emphasis on building envelope
Are the effects of airflow, temperature and humidity on VOC emissions significant?
Is further development of the complex model necessary?
Collaborations with others are encouraged
Actions
Focus on office furniture and other indoor materials, and important compounds (such as formaldehyde)
Demonstrate the importance of airflow and temperature on the VOC emissions
Focus on the model applications
Collaborated with Mark Mason/EPA and Al Hodgson/BAA
Continued to interact/exchange with
John Little, Virginia Tech
Yinping Zhang, Tsinghua University
Francis Allard, Universite de La Rochelle, France

8. Presentations in this Review
Overview (10 minutes by J. Zhang)
VOC emissions and exposure assessment (20 minutes, by H. Li)
Posters:
VOC extraction method development (by J. Smith, B. Guo, and J. Zhang)
Dual-chamber test method development (by J. Xu, J. Grunewald, M. Salonvaara, and J. Zhang)
Experimental and modeling of coupled heat, air, moisture and pollutant transport in residential wall assemblies (H. Li, M. Salonvaara, J. Zhang, and J. Grunewald)
CHAMPS-BES (by J. Grunewald, A. Nicolai, and J. Zhang)

9. VOC Emissions and Exposure Assessment
Hui Li, Jing Xu, J.S. Zhang, J. Grunewald, and M. Salonvaara
Syracuse University

10. Objectives Examine the existing emission test protocols (methods)
Develop emission test protocol for multi-layer system (VOC from inner layer)
Predict long-term occupants exposure to VOCs emitted from building materials and office furniture
CHAMPS-BES model (T,RH, and airflow effect)
Component to system prediction
Use the results of component performance test to predict the system performance

11. Emission Test Principle & Application Overview
L, ACH, T, RH, v, Δt
Sorption effect
Multilayer structure
Component to system
CHAMPS-BES, case study
? Same emission behavior
Emission test
Prediction Q
Q, C
C, Exposure
Emission model, e.g. power law & exponential V A
L= A/V
ACH = Q/V
CE
Short term emission test
Long-term VOC concentration
? Short-term to long-term
Emission models applicable?
Long-term prediction accuracy
CHAMPS-BES

12. Emission Testing Methods
OSHA
Limit
Formaldehyde Concentration
EPA/RTI ETV Test
Greenguard Test
LEED-CI
Limit
Greenguard Model
Zhang/BIFMA Test
Power-Law Model
CA-1350
Limit
CA 1350 Test
Days After Unpacking
1. All Concentrations Shown are Hypothetical.
2. CA 1350 Requires 10 Days Conditioning

13. Wood-based Workstation for Private Offices
Normalized emission factors over time for acetaldehyde and formaldehyde

14. Multi-layer System
Building envelope system and almost all the office furniture structure are multi-layer system
VOC3
VOC2
VOC1
varnish, <1/32”
wood veneer , 1/32”
particle board, 1 1/8”
wood veneer , 1/32”

15. Simulation Results with a Multilayer Diffusion Model
Redistribution prior to testing
Emission factors over time
From t= -10d to t=0

16. Identification of VOC Source - Headspace Analysis
Particleboard in headspace
Wood veneer in headspace
Particleboard
Wood veneer
C (mg/m3)
% of TVOC
HEXANAL
16023
45%
296
10%
PENTANAL
3929
11% 48
HEPTANE
3872
OCTANE
2338 7%
ALPHA-PINENE
2172 6%
ACETIC ACID, ANHYDRIDE WITH FORMIC ACID
1327
NONANE, 3,7-DIMETHYL-
174
HEPTANE, 5-ETHYL-2,2,3-TRIMETHYL-
157 5%
DECANE, 3,8-DIMETHYL-
133 4%
29 compounds from particleboard and 25 compounds from wood veneer were identified

17. Distribution Effect (Formaldehyde Emission)
VOC mass concentration in chamber, mg/m3

18. Advantage of Model-based Approach
Predict long term performance while taking into account the following effects:
Multi-layer effect
Effects of initial conditions
Effects of environmental conditions

19. Airflow and Temperature Effect on VOC Emissions
VOC emissions from building envelopes are largely affected by the leakage airflow and temperature
A full-scale wood frame residential wall assembly was tested
Major leakages characterization
Airflow effect on VOC emissions
Temperature effect on the emissions
CHAMPS-BES prediction of VOC emissions from the wall assembly
Contribution to long term exposure for given room conditions
With given parameters, CHAMPS-BES model can predict VOC emissions from the wall assembly and further, can estimate the contribution of the wall assembly to long term occupant exposure under given room conditions

20. Test Wall with Instrumentation
Pressure transmitter
Climate chamber
(Outdoor)
IEQ chamber
(Indoor)
VOC sampling port
VOC injection port S1 S2 S4 S3 S5 S6 S7
RH28
RH29
T/RH sensor
Floor space
Roof space
Bottom wood
Insulation
OSB
Gypsum board
Top wood
Facing of insulation
Supply
Return
Test wall

21. The Coupled Indoor/Outdoor Environmental Simulator (C-I/O-ES)
HVAC for
IEQ chamber
HVAC for
climate chamber
Climate
chamber
Test wall
Control
station
IEQ
chamber
The Coupled Indoor/Outdoor Environmental Simulator (C-I/O-ES)

22. VOC emission Test (Depressurized IEQ Chamber)

23. Simulation of Airflow Effects
CHAMPS run with full BES models
VOC-field in log10(mg/m3)
BES
Air + VOC
convection
Air + VOC
diffusion
Air flow
Zone

24. Temperature, Airflow Effect on Emission & Transport
Climate chamber, outdoor
IEQ chamber, indoor
Air flow
Since most of the emissions was carried by the airflow, rather than emitted from the interior surface, S5 can be

25. Temperature and Airflow Effect on VOC Emission
Climate
IEQ
Since most of the emissions was carried by the airflow, rather than emitted from the interior surface, S5 can be

26. Simulation of Airflow and Temperature Effects

27. Conclusions from Emission Testing So Far
Current test method can capture the single or outer layer emission characteristics
For VOCs from inner layer, model-based test method is needed to predict long term emission
Multi-layer structure
VOC source, initial concentration (product history)
Diffusion and partition coefficient
CHAMPS-BES can predict effects of leakage airflow and temperature conditions

28. Further Investigation Plan
Develop test protocol for inner-layer source VOC emission test
Longer-term testing for model validation
Material testing layer by layer
Estimation of long term VOC exposure –CHAMPS-BES
Case study, building material and furniture
Component testing to system performance prediction
Effect of humidity and temperature on formaldehyde emissions
Model development of humidity dependence of model parameters
Dual chamber test for diffusion coefficient
Extraction method for initial content and partition coefficient
Comparison with collaborator's data
Virginia Tech
Tsinghua University
Universite de La Rochelle, France