The Light Lady on Lighting at Work

Chris Terry, director at Insight Workplace Health, recently introduced me to Dr Shelley James, also known as the “Light Lady”. Here are the highlights from our conversation about work, health and light.

LS: Hi Shelley. You are the first light specialist I have met in my career! Tell us about your work and how you got here.

SJ: There are plenty of lighting designers, but not many light and health specialists out there yet… although that is starting to change. Interest in, and understanding of, the importance of light in the places where we live and work is definitely growing. At the same time, more affordable lighting options are evolving to meet that demand. It’s an exciting time to be working in this sector - making sure we base our recommendations on evidence is more important than ever.

My own professional background is quite varied. My academic career began in Paris, where I studied colour and light in textiles, essentially exploring how light interacts with surrounding colours. That led me into a career in branding, where I worked with large corporate organisations to help them use colour and light to shape messaging and culture.

After recovering from a serious head injury, my career evolved again and I completed a PhD on pattern perception and how we understand space. That then led me to working with glass, particularly using glass in ways that create colour change under different lighting conditions. At that point, I then qualified as an electrician in order to wire up my own work safely, while also completing lighting design training to deepen my understanding of the aesthetic side of lighting.

During Covid-19, I set up a light library to help people choose lighting in context. I also ran a social media campaign supporting young people to make better lighting choices in home-learning environments.

Now, I spend most of my time applying what I have learned over the years to help a wide range of clients make sense of light. That includes advising different workplaces, as well as guiding manufacturers on how they can improve the products they design and deliver.

LS: What an interesting background. Light is clearly a common thread throughout. In your work, you talk about light in relation to sleep, focus and mood. All of these feel intuitive to an extent, but beyond seasonal affective disorder, I don’t know much about the evidence base. Can you tell us more about these themes, and how they are relevant to the workplace?

SJ: Yes sleep, focus and mood are the three main areas where I think light can have the most tangible impact.

Let’s start with sleep. Early research shows that the human brain looks for contrast between day and night, and is particularly sensitive to sky-blue wavelengths. In practice, this means that if there is not enough contrast across the day, normal circadian rhythms can be disrupted. Sleep and wakefulness become less well regulated. Evidence suggests this can then have knock-on effects on health, including through inflammatory pathways. We can use light upstream, and quite strategically, to help regulate sleep and wake cycles. Light is the brain’s single best indicator of day and night.

That same pathway is also relevant to focus. It influences attention, concentration and memory formation. It is well established that the visual environment affects how safe and comfortable people feel when trying to work or learn. Anything from visual discomfort to movement in peripheral vision can affect focus. Studies suggest that bright, cool light can have a “coffee-like” effect on the brain, sharpening attention.

Softer lighting, meanwhile, can be more conducive to collaborative tasks. With remote and hybrid working now much more common, getting lighting right on site can be especially powerful. Generally, people and their employers want time spent on site to be meaningful, so people come together for a purpose, and space and lighting have a contribution to make to that.

A big part of my work is helping workplaces understand how they can tune light to task. In fact, giving individuals more control over the lighting in their own environment can be a very effective way of increasing autonomy, as well as improving focus and engagement.

Finally, there is also evidence that light affects mood. We are speaking on a slightly cloudy day in March. I haven’t measured the outdoor light levels, but I would estimate them at around 10,000 lux. Around 30 minutes of daily exposure to light at that level can reliably improve mental state and reduce the risk of developing some forms of mental ill health.

LS: I can see how useful all of this is for employers and for people at work, whatever the setting. I can think back to roles I have done in poorly lit environments, or winter shift work where it feels like I barely saw daylight for weeks. At the same time, I think workplaces are generally behind the curve on this. I cannot think of any examples where people I have worked with were using light proactively, rather than adjusting it reactively, for example, in response to DSE issues such as glare.

SJ: I agree. Light is still behind other environmental and ergonomic workplace factors. For example, if you arrived at work and were asked to sit on a stackable plastic chair all day, you would challenge it. Employers would know that was not appropriate, which is why we do not see that degree of deviation from accepted standards in workplace seating.

But there is much less knowledge and practical application when it comes to light. I visit workplaces where I see the lighting equivalent of a stackable plastic chair, and neither the worker nor the employer fully realises the negative impact it is having on health or productivity.

Sometimes, during light audits, I find that a workplace has recognised a problem — but the response is not always appropriate. I have walked into spaces where people are wearing sunglasses and caps indoors to cope with glare.

Light is an important piece of the workplace health and productivity puzzle, and the evidence base is growing. Some research even suggests that a proportion of neck and back pain attributed to musculoskeletal causes is actually linked to lighting.

LS: Can you share a few examples where light has been used proactively at work to support workforce health and productivity?

SJ: There are two main settings that I see as ahead of the curve.

The first is smaller teams that have a close relationship with the building they work in. Residential care is a good example. These settings often have smaller workforces and leadership teams who actually own the building. That proximity makes it easier to invest in lighting in a thoughtful way.

The second is much larger corporate organisations with the resources to invest in workforce health and productivity. They may be tenants rather than owners, but they have still found ways to make meaningful changes and improvements. The research is there to back it up. A study of an intervention and control group in an office environment found that when audited, the existing lighting set up for workers was actually more suitable for winding down to sleep.

The intervention group experienced a change to circadian lighting. During some parts of the day, this meant the office lighting doubled in brightness. This led to a tangible increase in perceived productivity and task performance. At the end of the trial, when participants were moved back to the previous lighting set up many believed the lights were off entirely!

LS: It’s great to see some evidence generation in this space. Quite contrasting examples between SMEs and big corporates as invested stakeholders. Can you suggest some lower-cost, entry-level interventions for workplaces that do not own their building?

SJ: Yes, there are always lower-cost ways to start, and some of these basic interventions can make a real difference.

The first thing I would recommend is looking at task lighting. By that, I mean managing ambient lighting while also offering options for specific tasks. Window coverings can help, as can physical screens to manage glare and create a sense of visual privacy.

In open-plan environments especially, it is often about creating spaces within spaces, giving individuals enough control to optimise their own working conditions.

LS: Control is such an important aspect of working conditions, and links closely to the HSE Management Standards on work-related stress. I tend to think about control more in terms of workflow, but you are absolutely right that control over the working environment is a big factor too. How does that relate to the neurodiverse groups you work with?

SJ: I definitely see that people with sensory processing differences are at higher risk of health and productivity impacts from unsuitable lighting. Sound is something more workplaces are aware of in this context, and it can sometimes be easier to manage, for example, with noise-cancelling headsets. There is no equivalent ‘personal protective equipment’ for poor lighting.

That said, sound, light and thermal comfort do not operate in isolation. These factors interact. Noise, for example, can affect visual function.

It is also important to remember that our relationship with light varies from day to day and from person to person. Someone who has had a poor night’s sleep might need bright, cool light to support productivity. Someone else might find that uncomfortable and prefer softer, warmer light when tired. There is no single answer for everyone, which is why flexibility and control matter so much.

LS: Thanks Shelley! Lots to think about.

My main takeaways:

1. Think more deliberately about light at work. Light is an active driver of sleep, focus and mood.

For employers, this means shifting from a reactive approach (fixing glare, meeting minimum standards) to a proactive one. For individuals, it’s worth reflecting on whether lighting at work is helping or hindering ability to focus.

2. Create autonomy through lighting

One of the strongest themes in our discussion was control.

We often think about control in terms of workload or flexibility, but environmental control is just as important. Lighting is a powerful and underused way of giving people agency over how they work. This may be particularly important for neurodivergent individuals, who could be more sensitive to lighting conditions. Unlike noise, there is no easy “headset equivalent” for poor lighting. Good design and flexibility are therefore even more critical.

3. Match lighting to task

Shelley outlined that there is no single “ideal” lighting setup.

Instead, lighting can be tuned to task

●  Bright, cool light → supports focus, alertness, analytical work

●  Softer, warmer light → supports collaboration, conversation, creative thinking

In open-plan environments, this becomes especially important. Rather than uniform lighting across a whole workspace, workplaces can create zones for different types of work, using task lighting. Offering control can transform our experience of a space and our sense of being valued and supported.

This idea of “tuning light to task” (and to the individual) mirrors the way we already think about meeting spaces, quiet zones and collaboration areas, yet it is rarely applied through a lighting lens.

If you would like support reviewing how lighting, environment and wider ergonomic factors may be impacting health, wellbeing and performance in your workplace, our occupational health team can help.

We work with organisations to identify practical, evidence-based improvements that support employee comfort, reduce risk, and enhance productivity across a range of working environments.

To discuss your workplace needs, please get in touch with our team.