Industry experts are gathering to begin work on version one of the lighting circularity measure TM66.
The technical memorandum, which measures the circular performance of luminaire, has been in a preliminary ‘beta mode’ since its introduction, says its authors, Cibse’s Society of Light and Lighting.
The document won a prestigious Build Back Better Award on its publication on its publication in 2001 and was quickly adopted by the lighting industry.
Major lighting design practices and organisations are using the metric in their procurement and specification policies, and many manufacturers have rated their luminaires on the TM66 scale, which gives a number between 1 and 4 similar to a vehicle’s NCAP safety rating.
Now the TM66 development team, the founding partners and parallel organisations are set to gather to work the official first version of the standard.
An update will be presented in September at the Circular Lighting Live 2025 event in London on Thursday 25 September.
Sections of the document likely to change include:
• Materiality, the identification and appropriately scoring of those aspects of a luminaire’s design, materials, construction or ecosystem that have the most impact on circularity
• Precision and transparency, especially related to language, reporting and evidence
• Greenwashing, the reduction of the possibilities of the metric being used to make misleading or false claims about the environmental benefits of a light fitting.
TM66 has two key tools which the experts will review. These include CEAM-Make, a tool for manufacturers to complete which comprises 66 questions under four tabs – product design, manufacturing, materials and supporting ecosystem.
Each question is rated and then scored between 1-4, where 1 is status quo and 4 is outstanding.
At the end of the assessment a total is generated, and a high score indicates a lighting product with good to outstanding Circular Economy credentials.
Another tool in the document is CEAM-Design, a demand-pull tool which contains 20 questions and is aimed at designers or specifiers to enable them to quickly understand what level of circular performance a not-yet-tested product has. Again, at the end of the assessment a total is generated.
• Learn about TM66 at Circular Lighting Live 2025, Recolight’s flagship conference and exhibition, which takes place on Thursday 25 September 2025 at the Minster Building in the City of London. Free to specifiers, Circular Lighting Live 2025 will feature leading experts, specifiers and policy makers who will share their insights into forthcoming standards and legislation, emerging technologies and new business models. More info: www.circularlighting.live
