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This section describes the outputs for the Case window.
Physical Results:
• Speech Intelligibility
• Desktop Illuminance
• Glare
• Listen to Environment
Detailed Results:
• Desktop Illuminance < 80% of mean
• Screen Luminance
Satisfaction Results:
• Satisfaction with Privacy
• Satisfaction with Lighting
• Satisfaction with Ventilation
Physical Results:
This tab displays the primary outputs of lighting and acoustics calculations performed by COPE-ODE.
Speech Intelligibility:
There are both a numeric and a graphic display showing the value of speech intelligibility index (Sii). The graphic display is a "meter" with a scale of 0-0.5. Note that a lower value of Sii is better for speech privacy.
If no criteria are set for Sii in the folder, the graphic display will have a simple white background.
If criteria are set for Sii in the folder, the background for the "meter" will be colored to indicate the criteria; in this example, less than 0.2 is good, greater than 0.3 is bad, and in between is "just ok". 
Desktop Illuminance:
There are both a numeric and a graphic display for desktop illuminance. Note that this is the illuminance provided by the lighting design specified for the case (see Case Inputs ). It does not account for daylight or task lighting.
The graphic display is a "meter" with a scale of 0-1000 lux if using SI units and 0-100 footcandles if using imperial units. The blue vertical bar shows the value of mean desktop illuminance. The blue horizontal bar is an indicator of uniformity; 68% of illuminance measurements on the desktop can be expected to be in the range indicated by this bar.
If no criteria are set for desktop illuminance in the folder, the graphic display will have a simple white background.
If criteria are set for desktop illuminance in the folder, the background for the "meter" will be colored to indicate the criteria; in this example, the criteria is satisfied if desktop illuminance is between 320 and 540 lux; outside this range the criteria are not satisfied.
Glare:
Glare on the video display terminal (VDT) is shown as "Low", "Med" (medium), or "High". 
Images on the right show the lighting layout (ceiling view) and the glare on a black screen of the VDT with this lighting. Click on the smaller image to get a larger image in a new window.
Listen to Environment:
This feature has not yet been implemented.
Detailed Results:
This tab displays some of the less commonly used results.
Desktop Illuminance < 80% of mean
This measure is the percent of desktop illuminance measurement points that are less than 80% of the mean desktop illuminance.
Screen Luminance
This is a measure of the luminance on the partition in the area immediately behind the VDT.
Satisfaction Results:
This tab displays satisfaction issues that have been identified by COPE-ODE.
indicates an item that has a negative impact on satisfaction.
indicates an item that has a negative impact on satisfaction.
Workstation area is small
Smaller workstations tend to be associated with a lower level of satisfaction with privacy. The COPE study suggests that workstations having an area less than 64 ft2 (5.95 m2) be used with caution. This does not mean that smaller workstations cannot be satisfactory. However, you should consider other factors which could improve satisfaction with privacy.
Speech intelligibility is high
A higher value of Sii, which indicates that speech from adjacent workstations can be heard more easily, is associated with a lower level of satisfaction with speech privacy. The COPE study suggests that the value of Sii should be less than 0.35.
Screen height is low
Lower partition (screen) height tends to be associated with a lower level of satisfaction with privacy. The COPE study suggests caution in using workstation screens having an height less than 54 inches (1.37 meters). This does not mean that screens lower this cannot be satisfactory (although screens which are too low to prevent line of sight between seated occupants are definitely not recommended). However, you should consider factors which could improve satisfaction with privacy.
Background noise is high
Higher levels of background noise have the benefit of improving speech privacy (i.e. reducing Sii). However, high background noise is also associated with lower satisfaction. The COPE study suggests that background noise should be kept below 50 dBA.
Background noise is low
Lower levels of background noise have a negative effect on speech privacy (i.e. increased Sii). Low background noise in itself is also associated with lower satisfaction (yes, it can be too quiet). The COPE study suggests that background noise should be kept above 44 dBA.
Speech intelligibility is low
A Sii value of 0.2 corresponds to "normal privacy". Any value lower than this is better than normal for an open plan office.
Desktop illuminance is low
Lower levels of desktop illuminance tend to be associated with lower satisfaction with lighting. The COPE study suggests that desktop illuminance be greater than 300 lux (27.9 footcandles). Applicable standards and regulations may contain a requirement of minimum desktop illuminance. NOTE: the value calculated by COPE-ODE does not account for task lighting.
Desktop illuminance is affected by workstation design (e.g. workstation size, partition height) as well as lighting design.
Glare is high
Glare on the VDT screen is the most common complaint about lighting in offices. The COPE study suggests that glare should be kept below the value shown as "high". Fixtures with prismatic lens generally produce high glare.
Lighting has magnetic ballasts
Magnetic ballasts operate at twice the rate of the AC supply (i.e., in North America, where 60 Hz is the supply rate, magnetic ballasts operate at 120 Hz). This flicker rate is detectable by the nervous system and is associated with reading disruption, lower visual performance, headache, and eyestrain. Magnetic ballasts are also not energy-efficient. Energy-efficient electronic ballasts operate at 20,000 - 40,000 Hz, which does not have these effects.
Screen height is low
Lower partition (screen) height tends to be associated with higher satisfaction with lighting. However, it also tends to have a negative effect on satisfaction with privacy.
More than half of workstations have window
The COPE field study found that having a window improves satisfaction with lighting. Other research has shown that people have strong preferences for windows. Access to a window, especially if it has a natural view, can reduce the strains that result from stressors on the job. However, windows also need shading to prevent problems with thermal comfort and glare.
Individual control of lighting
Research at NRC and elsewhere has shown that providing individual control over workstation lighting can improve satisfaction with lighting. People whose lighting suits their preferences show better mood and well-being. Individual preferences for lighting levels vary widely, and the only way to meet accommodate this variability is to allow individual control.
Satisfaction with Ventilation:
Screen height is high
Higher partition (screen) height tends to be associated with lower values of satisfaction with ventilation. The COPE study suggests caution in using workstation screens having an height greater than 66 inches (1.68 meters). This does not mean that screens higher than this cannot be satisfactory. However, if screens are higher this should be taken into consideration in the design of the ventilation system.
Individual control of ventilation
Other research has shown that providing individual control over ventilation can improve satisfaction. This is probably because it allows individuals to create conditions that suit their preferences and needs. Individual preferences vary widely, and the only way to accommodate this variability is to allow individual control.
