Extech Instruments CO220 User Manual page 8

SHORT-TERM EXPOSURE LIMIT (STEL)
STEL is the Short-Term Exposure Limit (15 minutes weighted average);
the meter updates readings every 60 seconds. If the meter has been
powered on for less than 15 minutes, the STEL value shows the
weighted average of reading taken since the unit was powered ON.
LPS%
LPS% represents Liters per second per person.
CFM/P
CFM/P represents Cubic Feet per Minute per person.
VENT.R (CO
CO -based demand-controlled ventilation refers to the practice of
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using carbon dioxide concentrations as an indicator for a per-person
ventilation rate. In this context, CO
respiration rather than as an indoor contaminant. The rate at which
people produce CO
duration and intensity of physical activity. The more exertion an
activity entails, the more carbon dioxide is produced.
CHANGING THE 2ND TIER DISPLAY COMBINATION
Repeated presses of the C/F-RH% button step through the following
combinations of parameters:

Humidity + Air Temperature

Humidity + Web Bulb Temperature

Humidity + Dew Point Temperature
-based demand-controlled ventilation)
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varies with diet and health, as well as with the
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is monitored as a byproduct of
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