VOC emissions - what you get and what you calculate

VOC Emissions 
what you get and what you calculate
Reinhard Oppl
Director VOC Testing
Eurofins Product Testing A/S
Galten / Denmark
Folsom / California
Shenzhen / China
July 2012
Test chambers
Photo: Eurofins Product Testing A/S
July 2012
Significance of test result
 What you get from chamber testing is:
Test chamber air concentration at given time mg/m³,
then we calculate from that:
 Emission rate per hour, mg/h
 Specific emission rate (emission factor),
 per area mg/m²h
 or per mass, per device, per unit
 Contribution to air concentration, mg/m³ (source strength)
in reference room or in real room after a specified time
 Compare with limit values (always given as air concentration)
July 2012
European Reference Room
 Reference room - not a test room, but just a model
 Needed for comparing test result with air concentration limit values
 European Reference Room (CEN TC 351):
 Floor area 12 m², Height 2.5 m, Volume 30 m³
 1 window, 1 door
 Then calculate loading factors (m²/m³) for walls etc.,
 ½ air change per hour
 Area specific air flow rate (m³/m²h) = ach / loading factor
 23 °C, 50% relative humidity
 As most products can be used in various exposure scenarios,
this room is used as general reference for all situations
 Testing shall simulate those rooms in small scale
Test chambers made of stainless steel or glass, 50 litres to several m³
July 2012
Different Exposure Scenarios
 US: Open-plan or private office, class room, residential
 Different in surface, room height, furniture, equipment, ventilation
 Why different exposure scenarios can make sense:
 Some products are manufactured only to e.g. offices, schools, etc.
and then are rated against specific conditions
 Ambition is to predict air concentrations in such rooms
 Why different exposure scenarios cannot make sense:
 Almost all products are used in all scenarios
 A product may pass one, but fail another scenario
 (How) Will product marketing distinguish?
 We need an unambiguous scale for rating products
Select one small room as worst-case scenario
Do not exaggerate precision in exposure scenarios;
e.g. round 1.89 m² to 2 m² (door in CA); 31.4 m² to 30 m² (walls in EU)
Emissions can vary over time ± 30-50%; testing uncertainty ± 30-50%
July 2012
VOC long-term emissions – schedule
 All programs evaluate in-use phase emissions
 Evaluation mostly after 28 days in Europe, after 14 days in USA
 Limits after 3 days cover renovation / refurbishing
 Testing in ventilated test chambers; no correlation with VOC content
Example of a decay curve
All emissions during lifetime =
VOC content
July 2012

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