Specifications

Monitor Selection Criteria
887
Table 15.4 Display Power Management Signaling
State Horizontal Vertical Video Power Savings Recovery Time
On Pulses Pulses Active None n/a
Stand-By No Pulses Pulses Blanked Minimal Short
Suspend Pulses No Pulses Blanked Substantial Longer
Off No Pulses No Pulses Blanked Maximum System Dependent
Virtually all monitors with power management features meet the requirements of the United States
EPA’s Energy Star labeling program, which requires that monitor power usage be reduced to 15 watts
or less in standby mode. However, some current monitors also comply with the far more stringent
Energy 2000 (E2000) standard developed in Switzerland. E2000 requires that monitors use less than 5
watts when in standby mode.
Emissions
Another trend in green monitor design is to minimize the user’s exposure to potentially harmful elec-
tromagnetic fields. Several medical studies indicate that these electromagnetic emissions can cause
health problems, such as miscarriages, birth defects, and cancer. The risk might be low, but if you
spend a third of your day (or more) in front of a computer monitor, that risk is increased.
The concern is that VLF (very low frequency) and ELF (extremely low frequency) emissions might
affect the body. These two emissions come in two forms: electric and magnetic. Some research indi-
cates that ELF magnetic emissions are more threatening than VLF emissions because they interact
with the natural electric activity of body cells. Monitors are not the only culprits; significant ELF
emissions also come from electric blankets and power lines.
Note
ELF and VLF are a form of electromagnetic radiation; they consist of radio frequencies below those used for normal radio
broadcasting.
The standards shown in Table 15.5 have been established to regulate emissions and other aspects of
monitor operations. Even though these standards originated with Swedish organizations, they are rec-
ognized and supported throughout the world.
Table 15.5 Monitor Emissions Standards
Standard Established Date
Name by Established Regulates Notes
MPR I SWEDAC
1
1987 Monitor emissions Replaced by MPR II
MPR II SWEDAC
1
1990 Monitor emissions Added maximums for ELF and VLF;
minimum standard in recent monitors
TCO
2
TCO
2
1992, 1995, 1999, 2003 Tighter monitor emissions limits than
MPR- II; power management TCO
‘95, ‘99, and ‘03 add other classes
of devices to the TCO standard
1. The Swedish Board for Accreditation and Conformity Assessment
2. Swedish abbreviation for the Swedish Confederation of Professional Employees
Today, virtually all monitors on the market support TCO standards.
Chapter 15
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