Tuning the Spectrum: Light, Health, and the Pursuit of

Happiness

Leslie M. North, IALD, PE, LC, LEED AP Principal

Aurora Lighting Design, Inc.

Top 4 Healthcare Drivers

• Attracting patients • Addressing declining

work pool • Improving patient

outcomes • Improving financial

performance

“My favorite material is light. Light is for

comfort. Together with

space, light is the key to the future of

Architecture.”

- Santiago Calatrava

What does Tuning the Spectrum Mean?

Dynamic Terminology

• Dimming • Color Changing Color Preference

• Warm-Dim • Color Tuning • Circadian Reinforcement /

Tracking Alertness Therapy /

Circadian Mimicking

What Is White?

What Is White?

3500K

BBL

16 SDCM

4 SDCM

<3 SDCM

7 SDCM

What Is White?

Source: Acuity Brands

Color Changing (Light for Entertainment / Distraction)

Color Preference (Light for Mood / Expression)

Color Preference (Light for Mood / Expression)

Source: Philips

Warm-Dim (Light for Nostalgia / Intimacy)

• Decrease Color Temperature with Intensity

• Color Rendering across dimming range

Warm-Dim (Light for Nostalgia / Intimacy)

• Factory set v. User selectable

• Linear, Black Body, or Other

• Typically 2 or 3 CCT boards cross-faded

Color Tuning (Light for Consistency / Refinement)

• Can you Match Sources?

• Color Temperature • Color Rendering • Tint Control • Binning Tolerances

& Tolerance Over Time

Color Tuning (Light for Consistency / Refinement)

• Can you Match Sources?

• Color Temperature • Color Rendering

Color Tuning (Light for Consistency / Refinement)

• Tint Control • Multiple Color Point

Presets • Binning & Shift Dimming Over Time

4000K

BBL

4100K

3900K

Color Tuning (Light for Consistency / Refinement)

Color Tuning (Light for Consistency / Refinement)

Natural/Enhanced Color Balanced Color Vivid Color

Source: Acuity Brands

Circadian (Light for Natural Body Function)

Circadian Reinforcement / Tracking Alertness / Circadian Mimicking

Circadian Reinforcement (Access to Windows)

• Preterm infants Gained more weight Fewer days on ventilation

and phototherapy Enhanced motor function

Caution: Need Shielding; Overexposure may lead to retinal damage

Circadian Reinforcement (Access to Windows in “Sunny Room”)

• Decreased Length of Stay • Mortality Rate Lower • Improved Sleep Quality • Reduced Agitation in

Dementia Patients • Better Pain Management

Circadian Reinforcement (Light for Natural Body Function)

Source: Philips

• Premise is that occupant is diurnal • Can we truly mimic nature? • Energy Codes? Daylight Harvesting?

Circadian Reinforcement (Light for Natural Body Function)

Source: Visa Lighting

• Don’t forget the DARK nights • Low light charting

Control Systems Protocol

• Electronic Low Voltage (2-wire) • Fluorescent 3-wire • 0-10V (4-wire), multi-channel • DALI (4-wire) (v. 2.0) • DMX (4-wire) &

DMX/RDM (2-wire) • ZigBee (wireless) • Proprietary

Dimming Performance

100% 90 80 70 60 50 40 30 20 10 0

100%

90

80

70

60

50

40

30

20

10

Perceived Light

Dim

mer

Mov

emen

t

Linear VS Logarithmic Linear 50% = 67% Light Logarithmic 50% = 50% Light

Intelligent Driver

Dimming Performance M

easu

red

Ligh

t

100% 90 80 70 60 50 40 30 20 10 0

100%

90

80

70

60

50

40

30

20

10

Perceived Light

• 10% = 32% Perceived Load Shedding – High/Low

• 5% = 22% Perceived Energy Management Dimming

• 1% = 10% Perceived Daylight & Conference Rooms

• 0.1% = 3% Perceived Highest-Performance Spaces

Controls Issues

• Integration w/ other trades Shades, BMS, Nurse

Call • Integration w/ other

lighting/controls • Programming • User Interface • Overrides Code Blue, Nap time

Controls Issues

• Flicker • Unintended Color

Shift • All Dim to Same Color

at Same Rate

Source: Lighting Research Center at RPI

LEED v.4 for Healthcare Lighting Quality Point

• Individual control • Control from patient

bed • Multi-zone control for

all multi-occupant spaces At least 3 levels or

scenes

Circadian Reinforcement (Alertness / Circadian Mimicking)

• Dealing with Shifted Schedule Occupants

Source: nyas.org

Circadian Reinforcement (Alertness / Circadian Mimicking)

• Light Therapy Areas? • Separation from Diurnal

Thank You

Leslie M. North Principal

www.AuroraLD.com