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Visual lighting design

Adequate light levels are needed for a broad variety of activities, including reading various qualities and types of print, and working on detail-oriented tasks. Brightness levels also contribute to the perception of spaciousness, as well as to the overall visual appeal of illuminated spaces. Targeted task lighting can provide the necessary amount of light at workspaces without over-illuminating ancillary spaces; ambient light levels of 300 lux are sufficient for most tasks. Pairing adjustable direct task lighting with indirect or diffuse ambient lighting allows user customization and good visual acuity while providing more suitable background light. Light intensity for visual acuity is measured in lux (or foot candles), which is a measure of the way the eye responds to light weighted to the response of the cone cells—the main photoreceptors for daytime vision, located on the retina of the human eye.

Part 1: Visual Acuity for Focus

The following requirements are met at workstations or desks:

a. The ambient lighting system is able to maintain an average light intensity of 215 lux [20 fc] or more, measured on the horizontal plane, 0.76 m [30 inches] above finished floor. The lights may be dimmed in the presence of daylight, but they are able to independently achieve these levels.
b. The ambient lighting system is zoned in independently controlled banks no larger than 46.5 m² [500 ft²] or 20% of open floor area of the room (whichever is larger).
c.81 If ambient light is below 300 lux [28 fc], task lights providing 300 to 500 lux [28 to 46 fc] at the work surface are available upon request.
Part 2: Brightness Management Strategies

Provide a narrative that describes strategies for maintaining luminance balance in spaces, which takes into consideration at least two of the following:

a.174 Maximum brightness contrasts between main rooms and ancillary spaces, such as corridors and stairwells, if present. For example, projects may establish that, while still maintaining lighting variety, a main room cannot exhibit 10 times greater or lesser luminance than an ancillary space.
b.174 Maximum brightness contrasts between task surfaces and immediately adjacent surfaces, including adjacent visual display terminal screens. For example, projects may establish that, while still maintaining lighting variety, a surface cannot exhibit 3 times greater or lesser luminance than an adjacent surface.
c.174 Brightness contrasts between task surfaces and remote, non-adjacent surfaces in the same room. For example, projects may establish that, while still maintaining lighting variety, a surface cannot exhibit 10 times greater or lesser luminance than another remote surface in the same room.
d.174 The way brightness is distributed across ceilings in a given room that maintains lighting variety but avoids both dark spots, or excessively bright, potentially glaring spots. For example, projects may establish that, while still maintaining lighting variety, one part of the ceiling cannot be 10 times greater or lesser luminance than another part of the ceiling in the same room.
Part 3: Commercial Kitchen Lighting

The following light levels are achieved:

a.123 Maintained average of at least 500 lux [46 fc] of lighting at countertops and other food preparation or production areas.
b.124 Maintained average of at least 200 lux [18 fc] of lighting in dishwashing areas.
Part 4: Visual Acuity in Living Environments

One or more light sources provide the following:

a. Maintain an average of 215 lux [20 fc] as measured 0.60 m [24 inches] above finished floor in the living room.
b. Maintain an average of 50 lux [5 fc] as measured 0.60 m [24 inches] above finished floor in the bedroom.
c. Maintain an average of 100 lux [9 fc] as measured at finished floor in the bathroom.
Part 5: Visual Acuity for Learning

The ambient lighting system at desks in classrooms for the specified age groups meet the following requirements:

a. Early education, elementary, middle and high schools, and adult education for students primarily under 25 years of age: Able to maintain an average of 175 lux [16 fc] or more measured on the horizontal plane, typically 0.76 m [30 inches] above finished floor. The lights may be dimmed in the presence of daylight, but they are able to independently achieve these levels.
Part 6: Visual Acuity for Dining

The ambient lighting system at dining surfaces for the specified restaurant types meet the following requirements:

a.174 Cafeterias: Able to maintain an average of 150 lux [14 fc] or more measured on the horizontal plane at the height of the dining surface. The lights may be dimmed in the presence of daylight, but they are able to independently achieve these levels.
b.174 Casual dining and fast food: Able to maintain an average of 100 lux [9 fc] or more measured on the horizontal plane at the height of the dining surface. The lights may be dimmed in the presence of daylight, but they are able to independently achieve these levels.
c.174 Fine dining: Able to maintain an average of 30 lux [3 fc] or more measured on the horizontal plane at the height of the dining surface. The lights may be dimmed in the presence of daylight, but they are able to independently achieve these levels.
Muscular
Nervous
Endocrine

Applicability Matrix

Core & Shell New & Existing Buildings New & Existing Interiors
Part 1: Visual Acuity for Focus - P P
Part 2: Brightness Management Strategies - P P
Commercial Kitchen Education Multifamily Residential Restaurant Retail
Part 1: Visual Acuity for Focus - P - - -
Part 2: Brightness Management Strategies - P - - -
Part 3: Commercial Kitchen Lighting P - - - -
Part 4: Visual Acuity in Living Environments - - O - -
Part 5: Visual Acuity for Learning - P - - -
Part 6: Visual Acuity for Dining - - - P -

Verification Methods Matrix

Letters of Assurance Annotated Documents On-Site Checks
Part 1: Visual Acuity for Focus Architect Policy Document Spot Measurement
Part 2: Brightness Management Strategies Professional Narrative
Part 3: Commercial Kitchen Lighting Architect Spot Measurement
Part 4: Visual Acuity in Living Environments Architect Spot Measurement
Part 5: Visual Acuity for Learning Architect Spot Measurement
Part 6: Visual Acuity for Dining Architect Spot Measurement
81

Ontario Ministry of Labour. Computer Ergonomics: Workstation Layout and Lighting. Toronto: Ontario Ministry of Labour; September 2004: 16.

53.1.c

The Ontario Ministry of Labour's "Computer Ergonomics: Workstation Layout and Lighting" provides a checklist for computer workstations, which includes checking that light levels fall within 300-500 lux, and also that task lights are provided if required.

123

U.S. General Services Administration (GSA). Lighting. 2003 Facilities Standards (P100). 2003 ed. Washington, DC: General Services Administration Public Buildings Service; 2003. http://www.gsa.gov/portal/content/101308. Reviewed July 2, 2014. Accessed October 30, 2014.

53.3.a

The lighting level values in the U.S. GSA’s 2003 Facilities Standards (P100) are set at 500 lux for kitchens.

124

University of California, Office of the President. Dining Services Ergonomic Design Guidelines. http://www.uhs.berkeley.edu/facstaff/ergonomics/pdf/DiningDesignGuidelin.... Published May 2012. Accessed October 30, 2014.

53.3.b

The Dining Services Ergonomic Design Guidelines recommends lighting levels between 70 and 100 foot candles in warewashing areas for the safety and wellbeing of foodservice employees.

174

American National Standards Institute and Illuminating Engineering Society of North America. American National Standard Practice for Office Lighting. New York, NY: Illuminating Engineering Society of North America; 2012. RP-1-12.

53.2.a

ANSI/IES RP-1-12 provides recommended luminance ratios for offices.

53.2.b

ANSI/IES RP-1-12 provides recommended luminance ratios for offices. It notes that studies suggest that ratios do not exceed 3:1 or 1:3 between a paper task and an adjacent visual display terminal.

53.2.c

ANSI/IES RP-1-12 provides recommended luminance ratios for offices. It notes that for ceiling luminance ratios, 10:1 is the maximum acceptable ratio.

53.2.d

ANSI/IES RP-1-12 provides recommended luminance ratios for offices. It notes that studies suggest that ratios do not exceed 10:1 or 1:10 between a task and a remote surface.

53.6.b

ANSI/IES RP-1-12 provides Table B1 for recommended maintained illuminance targets for the horizontal plane. Table B1h recommends a target value of 100 lux for casual dining and 200 lux for fast food dining.

53.6.a

ANSI/IES RP-1-12 provides Table B1 for recommended maintained illuminance targets for the horizontal plane. Table B1h recommends a target value of 150 lux for cafeterias.

53.6.c

ANSI/IES RP-1-12 provides Table B1 for recommended maintained illuminance targets for the horizontal plane. Table B1h recommends a target value of 30 lux for fine dining.