Specifications

N
2
O Monitor 3010
14 Instruction 19-9208
3.8 Zero Calibration
There are two methods available to perform a zero calibration:
• Fresh Air
• Nitrogen
Note that a span gas is not required. The monitor is digitally calibrated
and has a linear curve relationship between 0 and 1,000 ppm N
2
O. There-
fore a zero in fresh air or with Nitrogen will adjust the curve across its
full reading range.
Follow these guidlines when calibrating:
• A calibration can be performed after the monitor’s initial 30 minute
warm-up period has expired. A calibration should not be performed
immediately after the measurement of a high concentration of gas.
• A calibration should only be done in clean air prior to the monitor’s initial
use for the day, or after the unit has been switched OFF/ON. If clean air
is not available, zero the unit using Nitrogen.
WARNING! Never attempt a zero in the actual testing envi-
ronment. Zeroing in a contaminated environment can
cause erroneous gas readings.
WARNING! Do not perform a zero calibration if the air
temperature is below 60 °F (15 °C). Zeroing in cold air can
cause erroneous gas readings.
WARNING! Do not immediately perform a zero calibration
when the instrument has just been brought in from a cold
environment, such as a cold vehicle in the Winter. First allow
the instrument to warm up to the temperature at which
measurements are to be made before zeroing.
When using the monitor for . . .
• TWA readings – zero before starting each 8 hour measurement period.
• leak measurements – zero daily before initial use.
• background monitoring – zero when moving from place to place.