Research study

The positive impact of NatureConnect onalertness and vitality of office workers
July 2023

NatureConnect - Office study, July 2023

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Study indicates that NatureConnect can increase
alertness of office workers.
Study performed by Samantha Peeters & Dzmitry Aliakseyeu researchers at Signify.
A recent study has shown that NatureConnect has a positive impact on the alertness and vitality of office workers. In a mock-up office, participants were exposed to both the NatureConnect as well as standard office lighting and had to complete questionnaires and tasks related
to their well-being and performance.
For alertness (measured with the Karolinska Sleepiness scale), the analysis showed that towards the end of the day participants feel more alert under NatureConnect, helping them tocombat the natural decline in alertness.
Furthermore, the analysis of vitality (measured with Thayer's activation/deactivation list)
showed that for participants above the age of 41 NatureConnect helped them to feel morevital. The study indicates the NatureConnect can give office workers a boost during the day tohelp them maintain alertness and feel activated.

In interviews participants indicated, that they viewed
NatureConnect as activating.

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1. The power of daylight to people
In the western world we spend about 90% of our time indoors¹ ². Moreover, a lot of this indoor
time is spent inside offices. Different characteristics of the office, with lighting being one ofthem, plays an important role in office workers well-being and performance, making good lighting an important element within the office³. In the past, there has always been a large focus on
the so-called visual aspects of light, but not so much on the non-visual aspects of light.
Receiving enough light during daytime hours is important for our well-being, such as for performance, alertness, and vitality ⁴ ⁶. Especially when light has high melanopic activation (socalled blue enriched light) it can have beneficial effects on subjective alertness, vitality andperformance.⁶ ⁸ Furthermore, receiving enough light during daytime hours can result in a reduced sensitivity to the sleep disruptive effects of evening exposure to light⁹ ¹¹.

Besides the tendency of people to prefer natural light over artificial light¹² ¹⁴, it also seems that
exposure to natural environments and features can have positive effects on well-being¹⁵. For
example, previous work has shown that being exposed to nature, even for 3 minutes, can have arestorative effect on your mental energy¹⁶.
Traditional office lighting tends to be too dim and warm, delivering an insufficient amount ofblue light, thus not achieving the right levels for melanopic activation. In effect, this means thatmany of us work in biological darkness during the day.
Bringing NatureConnect into an office environment could potentially have positive effects on
the general well-being and performance of office workers, by increased light exposure (especially relating to supporting melanopic activation) as well as bringing the natural light inside
design aspect. To see whether NatureConnect indeed can bring these positive effects to an
office environment, a study was conducted.
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2. Exploring NatureConnect
The NatureConnect lighting innovation by Signify is built on proven Biophilic Design principles
to reconnect us to the outside world. It mimics the natural patterns of daylight to create comfortable, engaging and attractive indoor environments.
To see whether NatureConnect indeed can bring these positive effects to an office environment, a study was set up to answer the following questions.
What is the effect of NatureConnect on measures related to alertness and performance ascompared to standard office lighting?
What is the effect of NatureConnect on the light appraisal and experience as compared tostandard office lighting?

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3. Higher alertness at end of day under NatureConnect
Analysis of the Karolinska Sleepiness scale¹⁷ indicated that a significant interaction was foundbetween alertness and time of day. In the current study our participants performed the study
at either 12.00, 14.00 or 16.00. NatureConnect showed a positive effect on alertness and is
helping to combat the natural decline in alertness over the day, while in the standard officelighting condition the subjective alertness did not recover from the natural decline in alertness(p = <.05).
Besides the statistical evidence, 52% of the participants mentioned unpromted the alerting
and activating effects.
“It makes me feel like I’m really awake under this light, not that you are slowly losing energy.”“I noticed that in both conditions I am focused, but with NatureConnect I noticed that I am
sharper and quicker.”

Looking at cortisol production over the day(see Figure 1), this peaks around 08:30 and
slowly declines over the course of the day,with some food-induced peaks around noonand 18:00 ²⁰. Combining this with alertness andhomeostatic sleep pressure, this results inpeople becoming less alert over the day. The
difference in alertness levels between 12.00
and 16.00 can be quite big, leaving more room
for improvement in alertness around 16.00.

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4. Higher vitality under NatureConnect when ≥ 41
Aging has an impact on the eye, leading to yellowing of the lens and other vision related issues.
For example, ageing adults (60+) require three times more light than younger adults (<20)¹⁸ ¹⁹.
These changes to the eye will already begin to be noticeable after 40 and progress over time²⁰.
Since the average working population is 42²¹, it is relevant to take this into account.
When running the analysis on vitality (as measured by Thayer’s activation/deactivation list²²),
the effect of age was also explored. The dataset was split in two groups (participants <41 andparticipants =>41) and analysis showed a main effect of the light condition for the =>41 group(p<.01). The main effect indicates that participants who are => 41, feel more vital under the
NatureConnect energize setting when comparing this to standard office lighting of 500 lx.

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5. NatureConnect light conditions positively appraised
The current study showed a significant positive result of participants evaluating the
NatureConnect as more activating when compared to standard office lighting (p <.01).

This is in line with what participants have mentioned unprompted in the interviews as well:
Perceived alertness

Impact of skylight

52% of the participants mentioned terms
associated with alertness.

90% of the participants were positive about
the skylight, of those positive participants:

14% of the participants stated it gives themenergy- 48% perceived the skylight as a window- 31% perceived the skylight as a sun- 21% commented that it created a feelingof working outside

17% mentioned that light helped them withconcentration or focus

Better experience“I feel like I have more energy and am more
excited”“It’s great for me in working environment.
When it’s gloomy outside, I prefer to havethis.”“With this light you don’t feel like it’s winter,it’s like summer outside.”“It is nice to work in. It feels like you areoutside. Especially with the blue it makes
me feel like I can just look outside.”

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6. Method used
The study was a laboratory-based study using a mock-up office. Reasons for this setup was
the combination of a higher level of control but also increased ecological validity. A within (light
condition: NatureConnect Energize versus regular office lighting) subjects design with repeated measurements was employed, the conditions were counterbalanced. Participants came tothe lab on 2 separate occasions where they were exposed to one of the light conditions for 60
minutes (after an initial baseline exposure (regular office lighting) of 30 minutes). Per session
there were 1-3 participants, with the experiment leader present in the room as well. Sessions
were planned at 12.00, 14.00 and 16.00 and participants were asked to come back at the sametime for both sessions when possible. Sessions were performed in late fall/early winter from
November 21 until December 9.

Light conditions
For this study NatureConnect has been compared to standard 500 lx lighting. Tables below
show vertical light levels which are relevant for this study.
Table 1. Vertical light measurements with monitors turned off. Illuminance.

Desk 1 vertical

Desk 2 vertical

Desk 3 vertical

Regular office
Lighting

222 lx209 lx

213 lxNatureConnect

676 lx658 lx696 lx

Table 2. Vertical light measurements, with screens turned off. Melanopic equivalent daylight illuminance

Desk 1 vertical

Desk 2 vertical

Desk 3 vertical

Regular office
Lighting

156 m-EDI

147 m-EDI

149 m-EDINatureConnect

718 m-EDI

699 m-EDI

743 m-EDI

Participants
For this study the goal was to invite 30 participants who represent the office population. Participants were recruited via an external agency with the following criteria:• Work at least 20 hours per week in the office (doing desk work)• No eye conditions.
• Between 23 and 60 years old (equally distributed)
In the end 29 participants were invited. The average age of our participants was 40 (SD = 9,
range 27-59) which closely resembles that of the Dutch working population, for which the average age is 42¹⁵. For the quantitative analyses 1 participant had to be excluded. All participants
were included in the interviews.
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NatureConnect - Office study, July 2023

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