Green Label Plus

1. Review the GLP standard: Download the Green Label Plus testing criteria from the CRI website (carpet-rug.org) to understand the VOC emission thresholds your product must meet for each chemical compound tested.

1. Identify eligible products: Confirm that your product falls within the eligible categories — carpet, carpet adhesive, or carpet cushion — as GLP is specific to these flooring materials.

1. Select a CRI-approved laboratory: Choose an independent testing laboratory that is approved by CRI to conduct GLP emissions testing. CRI maintains a list of approved labs on its website.

1. Submit product samples: Send representative product samples to the chosen laboratory following their sample submission guidelines. Ensure samples are production-representative and properly labeled.

1. Undergo VOC emissions testing: The laboratory tests your samples in a controlled chamber environment, measuring emissions of a defined list of volatile organic compounds against GLP thresholds over a specified period.

1. Receive test results: The lab provides a formal test report. If all VOC emission levels meet GLP criteria, the product qualifies for certification.

1. Apply for certification with CRI: Submit the passing test report to CRI along with any required application materials and fees. CRI reviews the documentation and, upon approval, grants Green Label Plus certification.

1. List your product and use the label: Your certified product is added to the publicly searchable CRI database. You may use the Green Label Plus mark on product packaging, marketing materials, and specification sheets, subject to CRI's licensing terms. Plan for annual retesting to maintain certification.

Green Label Plus evaluates carpet, carpet adhesive, and carpet cushion products against a defined set of volatile organic compound (VOC) emission thresholds. Testing is conducted in controlled environmental chambers at CRI-approved independent laboratories, following protocols aligned with California Department of Public Health (CDPH) Standard Method v1.2 (formerly Section 01350), which is also the basis for LEED v4/v4.1 low-emitting materials credits.

The specific VOCs tested include total VOCs (TVOCs) as well as individual compounds such as formaldehyde, acetaldehyde, benzene, toluene, styrene, 4-phenylcyclohexene (4-PCH — a compound specific to carpet manufacturing), caprolactam, and other chemicals identified as relevant to indoor air quality. Each compound has a defined maximum emission concentration limit, typically expressed in micrograms per cubic meter (µg/m³), measured after a specified conditioning period.

For carpet products, 4-PCH is a particularly important marker compound, as it is a byproduct of styrene-butadiene latex used in carpet backing and has been associated with indoor air quality complaints. GLP emission limits for carpet are among the most stringent in the industry. Adhesive and cushion products are tested against their own relevant compound lists and thresholds appropriate to their chemistry. Products must pass all individual compound limits — there is no averaging or offsetting between compounds.

Green Label Plus is the dominant VOC emissions certification for carpet products in North America and is widely recognized as the industry standard for low-emission flooring in the commercial and institutional sectors. Since its introduction in the early 1990s, it has become a near-universal requirement for carpet specification in schools, healthcare facilities, government buildings, and corporate offices — particularly those pursuing LEED certification. Its alignment with CDPH Standard Method v1.2 and LEED v4/v4.1 low-emitting materials credits has cemented its relevance in the green building ecosystem.

The program's primary competitors in the broader flooring emissions space include FloorScore (administered by SCS Global Services, covering hard-surface flooring) and GREENGUARD Gold (UL Environment, covering a wide range of building products). NSF/ANSI 140 offers a more comprehensive sustainability assessment for carpet but is less widely adopted as a specification requirement. In practice, GLP is the default emissions credential for carpet specifically, while FloorScore fills the equivalent role for hard-surface products. Many major carpet manufacturers — including Shaw, Mohawk, Interface, and Milliken — certify virtually their entire commercial product lines under GLP.

Demand for GLP certification has remained stable and is supported by ongoing growth in green building construction and increasing regulatory attention to indoor air quality. California's stringent indoor air quality regulations have historically driven adoption, and as similar standards spread to other states and internationally, GLP's relevance continues to expand. The program faces some pressure from broader multi-attribute sustainability certifications (such as Cradle to Cradle), but for emissions-specific compliance in the North American market, GLP remains the benchmark credential.

The Green Label Plus program was developed by the Carpet and Rug Institute (CRI), the primary trade association for the U.S. carpet and rug industry, and launched in 1992. It grew out of earlier CRI efforts to address indoor air quality concerns that had emerged in the late 1980s, when "sick building syndrome" and VOC emissions from building materials became significant public health topics. The original CRI Green Label program established a baseline for emissions testing; Green Label Plus was introduced as a more rigorous tier, with stricter emission thresholds and a broader list of tested compounds, to meet the demands of green building specifiers and health-conscious consumers.

A pivotal milestone came when the California Department of Public Health developed its Section 01350 (later formalized as CDPH Standard Method v1.2), which became the technical foundation for LEED's low-emitting materials credits. CRI aligned GLP's testing protocols with this standard, ensuring that GLP-certified products would automatically satisfy LEED requirements — a strategic move that dramatically increased the program's commercial relevance. Over the decades, GLP has been updated to reflect evolving scientific understanding of VOC health impacts and to maintain alignment with successive LEED versions (v3, v4, and v4.1). Today, thousands of carpet, adhesive, and cushion products from manufacturers worldwide carry the Green Label Plus mark, making it one of the most widely recognized product environmental labels in the flooring industry.