Light

Question 1

sDA

Answer 1

Spatial Daylight Autonomy - a unit that indicates the percentage of floor space where minimum light levels can be met

Question 2

Illuminance

Answer 2

The amount of light falling into a specific surface area. Measured in Lux

Question 3

Light Exposure
1. Precondition or Optimization
2. Intent
3. Issue
4. Solutions

Answer 3

1. Precondition
2. Provide indoor light exposure in indoor environment through lighting strategies
3. Reduced exposure to light has been linked to health problems such as depression and cognitive function. Light exposure during day time has been linked to increases in productivity and sleep schedules.
4. Average sDA is achieved > 30% in regularly occupied areas or > 75% in common spaces. On the interior, at least 30% of the regularly occupied area is within 20 feet of envelope glazing.

Question 4

Visual Lighting Design
1. Precondition or Optimizaiton
2. Intent
3. Issue
4. Solutions

Answer 4

1. Precondition
2. Provide visual acuity for all users in electric lighting.
3. Light levels in a space can either increase or decrease the visibility of cues in a space. Age is an important factor in the amount of light required for visual acuity.
4. Use lighting recommendations provide by authorities to make sure requirements are met. For design these include the IES lighting handbook. Predetermined light levels can be met if more than 50% of the occupants are under 65 and at least 90% of the project area is comprised of offices, classrooms, lobbies.

Question 5

Circadian Lighting Design
1. Precondition or Optimization
2. Intent
3. Issue
4. Solutions

Answer 5

1. Optimization
2. support circadian rhythm through indoor light exposure and outdoor views
3. disruption of circadian rhythm has been linked to many health problems such as obesity and depression. Humans have been spending more time inside and exposure to natural light has been diminished.
4. Light levels must meet the standard on the vertical plane and follow either 150 EML or 240 EML

Question 6

Electric Light Glare Control
1. Precondition or Optimization
2. Intent
3. Issue
4. Solutions

Answer 6

1. Optimization
2. Minimize glare caused by electric light
3. Glare causes eye issues such as fatigue, headaches, and visual discomfort. Glare especially effects adults under the age of 50 which comprises a majority of the workforce.
4. 100% of light is emitted above the horizontal plane or achieves a Unified Glare Rating under 16

Question 7

Daylight Light Design Strategies
1. Precondition or Optimization
2. Intent
3. Issue
4. Solutions

Answer 7

1. Optimization
2. Provide daylight exposure while indoors
3. Since humans spend approximately 90% of their time indoors, increasing the amount of daylight has been shown to improve mood, and productivity.
4. Ensure that 70% of the workstations are near a window that has visibility and automatic controlled shades. Integrating solar shading controlled by occupants to prevent glare.

Question 8

Visual Balance
1. Precondition or Optimization
2. Intent
3. Issue
4. Solutions

Answer 8

1. Optimization
2. create lighting environments that enhance visual comfort.
3. Fluctuating light levels across a project can impact visual discomfort and lead to eye fatigue. Constant changes in lighting have been linked to distractions and decreased productivity.
4. Provide ambient lighting that means luminance ratios and any lighting changes (dim or brighten) over a 10 minute span.

Question 9

What are the two preconditions of “light”?

Answer 9

1. Light Exposure
2. Visual Lighting Design

Question 10

Daylight Simulation
1. Precondition or optimization
2. Intent
3. Issue
4. Solution

Answer 10

1. Optimization
2. Insure indoor daylight exposure through daylight simulation
3. Exposure to daylight has been proven to increase mood, and productivity. Indoor spaces with daylight have shown to contain fewer bacteria.
4. Project demonstrates through computer simulations that one of the following are achieved: 1) calculations provided by IES or CEM.

Question 11

Electric Light Quality
1. Precondition or optimization
2. Intent
3. Issue
4. Solutions

Answer 11

1. optimization
2. Enhance visual comfort and minimize flickering
3. Using electric light with high color rendering can improve visibility. Flickering lights have been associated with eye strain, headaches and seizures.
4. Utilizing light fixtures that emit a high quality of light in the space. and met the color rendering index (CRI) of > 90.