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SLL Webinar: Good indoor light makes people healthy and happy

10 March 2021 11:00 - 12:30


CPD Hours

10 March 2021 | from 11:00 GMT 

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The Society of Light and Lighting (SLL) will be joined by Jan Denneman, Chair of the Board for the Good Light Group. The webinar will begin with a presentation from Jan, following which there will be a panel discussion with SLL President Elect, Dr Ruth Kelly Waskett and Professor Peter Raynham. There will also be an opportunity for audience Q&A.

Scientific studies from recent decades make very clear that light is crucial for our health and well-being. Good light does much more than enable us to see. It is the most important “zeitgeber” for our brain and body to synchronize our internal circadian clock. 


A well synchronized circadian clock enables better sleep, more daytime energy, better mood and improvements in our resistance to several diseases. The best light to synchronize our circadian clock is daylight. This has the intensity and dynamics to do so effectively. Indoor lighting, however, is not intense enough and too static. It needs to be at least five times more intense and more dynamic than in current lighting practices. LED technologies make it possible to mimic the positive aspects of daylight indoors: attractiveness, dynamism, optimisation and personalisation. 


This offers vital opportunities for new lighting designs and solutions and a health and well-being revolution for all involved in the lighting of indoor spaces.

In his presentation, Jan Denneman will provide a summary of the key scientific insights in the field of good light will be given followed by some details of the activities The Good Light Group and its liaisons are developing to realize the fulfilment of our 2025 mission: that 1,000,000 people worldwide know about the beneficial effects of Good Light on the body and brain and that 100,000 people worldwide live, work and learn in buildings with Good Light.



Jan Denneman, Chair of the Board at Good Light Group

More than 40 years of experience in leading executive roles in innovation, marketing and business development. Initiated several international consortia, like the Global Lighting Association, Zhaga, the Connected Lighting Alliance, LightingEurope. President LightingEurope 2013-2017; President Global Lighting Association 2007 – 2017.

Cofounder and chair of the Good Light Group, a non-profit organization which promotes the use of Good Light indoors. Good light is natural daylight or electric light with comparable positive effects on people health and well-being. Good light helps synchronizing our circadian clock, enhances the quality of sleep at night, fitness during day time and mood.

Ruth Kelly Waskett Ph.D. CEng MCIBSE FSLL

Ruth is a lighting consultant with a background in engineering, lighting design and academia. She’s passionate about the role of daylight and sunlight in bringing buildings to life, and the impact of daylight exposure on the health and wellbeing of building occupants. Ruth worked as a mechanical building services engineer before specialising in lighting, giving her an appreciation of the key part played by lighting and daylighting in the wider context of sustainable building design. Ruth’s PhD research looked at the user experience of smart tint-able glazing in a UK office, and she has a particular interest in the real-life issues associated with automated building technology, particularly those that offer daylight control.

Ruth is President Elect of the Society of Light & Lighting (SLL), a part of the Chartered Institution of Building Services Engineers (CIBSE). She led the revision of the SLL Daylighting design guide in 2014 and is a regular contributor to various CIBSE and SLL guidance documents. She is also a visiting lecturer at the Bartlett School, UCL, with involvement in the MSc in Light & Lighting and MEng in Architectural Engineering.

Peter Raynham MCIBSE FSLL, Professor of the Lit Environment, Bartlett School of Environment, Energy and Resources, Faculty of the Built Environment, UCL

After a 20 year career in the lighting industry Peter jointed the Bartlett in 1996. His industrial career included working on lamp and luminaire development before progressing to lighting application. His initial role at the Bartlett was as a Research Fellow and working on a number of projects involving the areas of lighting simulation and lighting for the public realm. He later progressed to the role of lecturer and then senior lecturer where supervised a number of research projects and took on additional teaching duties. Peter became Professor of the Lit Environment in 2018. Peter is active in a number of lighting societies, he is a membership assessor for the Institution of Lighting Professionals (ILP), he was a Director of the International Association of Lighting Designers (IALD) and was President of the Society of Light and Lighting (SLL). He is a fellow of both the SLL and the ILP.

Peter is also active in the area of Lighting Standards, he chairs the British Standards committee on Light and Lighting and represents the UK on a number of international standards bodies.

This event was organised by the Society of Light and Lighting (SLL). If you have any questions, please contact or telephone +44 (0) 208 772 3685