Skip to main content
Welcome to the cutting edge of safety science—Learn more about our rebrand.
  • Feature Story

Breathing Easier: How UL Environment Tests Product Emissions for Cleaner Indoor Air

ul product emissions testing ul, ul product emissions testing

March 29, 2016

People in industrialized nations spend about 87 percent of their time indoors, subjected to indoor air containing volatile organic compounds (VOCs) released by wood products, flooring, carpeting, personal care products and electronics.

Increasingly, manufacturers are interested in developing low-emitting products, either to address customer concerns or to satisfy green building requirements. Developed by the U.S. Green Building Council in the late 1990s, LEED® is the pre-eminent green building certification and contains indoor air quality requirements. Federal, state and local governments as well as school districts encourage and incentivize building owners and developers across the country to pursue LEED® certification for their buildings. BREEAM, a building certification used in more than 50 countries around the world, also provides credits for the use of low emitting products in buildings.

Moreover, both retailers and consumers are becoming increasingly concerned about the health impact of products. New parents, in particular, are expressing greater concerns as they seek to build healthy homes and nurseries for their children; retailers are on the front lines as consumers are becoming more vocal and requesting information about the emissions levels from products.

To assist product manufacturers in addressing the increasing interest in low-emitting products, UL Environment can test the chemical emissions levels of a wide range of products found in homes and offices. Manufacturers who want to demonstrate that their products are low emitting can pursue GREENGUARD Certification, which provides buyers with confidence that the products emit low levels of chemicals.

When UL Environment receives a request from a manufacturer to perform GREENGUARD Certification for a line of products, the team identifies the differences between the various versions of the products within a product line to gain a better understanding of when, where and how the products were made. Then, the team develops a comprehensive test plan for all of the products.

Tests are conducted on newly manufactured products which are packaged in foil and polyethylene bags to help ensure the product is not contaminated during shipment and to avoid decaying emissions. Once the product is received at a the testing lab, it is placed inside high-polished, stainless steel chambers that create a standardized environment with purified air, to simulate an office building or home. Then, testing can begin.

First, UL Environment tests small representative samples of the product — such as leather from a product line of chairs — to go through screening tests called “profile tests.” If the samples pass, they move onto full certification testing on the representative products — such as the full chair. Scientists collect data for up to two weeks inside the chamber through the use of sorbent media, shipping the media to chemistry labs to identify the VOCs and measure the emissions levels.

With this data, they create a model to predict what people would experience through exposure to a product — i.e., potential health issues, irritation, odor, etc. If the product meets the emissions criteria, then the product will achieve GREENGUARD Certification. If the product doesn’t meet the certification requirements, the manufacturer can take the necessary steps to revisit their materials sourcing or manufacturing processes.

“With over 30 years of experience measuring VOCs, we have a large data set that helps us inform clients where their products stand in comparison with other products in the marketplace,” explained Scott Steady, UL Environment’s product manager for indoor air quality. “We can quickly identify the links between certain products and the health issues they may cause, and guide our clients towards low-emitting solutions.”

For more information on UL Environment, visit