Lighting consultants Nulty have worked with brands including Harrods, Ritz-Carlton and the Royal Albert Hall, but as director Emilio Hernandez told CLAD, their most significant project might simply be helping people to get a good night's sleep.

Founded in 2011, the firm has grown to have offices in London, Dubai, Beirut, Miami and Bangkok and it has worked across a variety of sectors, with projects having included restaurants, gyms, homes, stores, offices, hotels and public squares.

With its experience has come the recognition that good lighting design can no longer only be about what is good aesthetically but must also be about what is good for people.

Hernandez explained that the more Nulty looked into the impact light has on individuals, the greater they realised the impact was.

"We went back a step and took a wider, snapshot view of people's light diet and how they consume light throughout the day. Some of the research that we've undertaken and looked into has made it very clear that you can't look at one moment in time when you're looking at how light impacts people's sleep."

In 2018, Nulty began working with Imperial College London's department of endocrinology and architects Perkins and Will to better understand the effects of light in different volumes and colours on individuals.

"We realised that, if you're going to be trying to convince someone that you've got a certain environment outside in order to make them feel differently inside, there should probably be some science to back that up, because we're messing around with people's perception of what time of day it is," said Hernandez.

Although the study is ongoing, its findings are said to be supporting the wider body of research that Nulty has carried out – among them that we're much more sensitive to light than perhaps we realise, that different types of light can affect us differently and that more care can be taken about how we factor light into space design.

"There are three stages throughout the course of the day where light is much more likely to have an impact than others and we can be responsible with how we use light during those times," explained Hernandez.

"Things like the corridors and lobbies in hotels can be important. If you got out of a cab and you're feeling pretty tired, you don't then want to be blasted with light and then go into a room to try and sleep. So there's consideration about those routes through to people's rooms.

"Or even when you're getting up in the middle of the night and going to the loo, you don't want that big injection of light, because you're really sensitive to light at night and in the early morning, whereas during the day you need a much bigger dose of light for it to actually have a hormonal effect."

The problem, however, is that there's little in the way of standardised advice or even concrete guidance for how lighting should be factored into design from this perspective – so Nulty has begun developing a "manifesto for sleep" aimed at providing some of this.

Far from being a tome of rules that must be meticulously followed, the vision is for something that can simply guide people through some of the important things to consider, such as ways to eliminate light spill from devices, how to keep indicator lights on TVs out of view and how automated blinds and curtains can help people to wake up more naturally.

"Rather than just saying to everyone 'cut out all the light and have really low levels of light', if we can suggest that a dose of amber light by the bedside or within the room before going to bed, we could complement going to sleep," said Hernadez.

"To interior designers, we can say that having a very warm light – and giving them the exact wavelength – would be conducive to better sleep. It's a step forward and gives us another tool to help people get off to sleep."