Specifications

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6.6.2.2 Gas Quality and Gas Quality Ratios
The Envision® gas analyzer measures concentrations of three gases: CH
4
, CO
2
and O
2
. The balance gas is calculated by
subtracting the total of these three gas qualities from 100%.
6.6.2.2.1 Gas Qualities
CH
4
- Methane
CH
4
is measured via an internal Infrared sensor. The measurement range of the sensor is 0-100% CH
4
.
CH
4
– LEL (lower Explosive Limit)
By tapping the CH
4
box the Trimble handheld computer will display the CH
4
LEL%. The user can return
to the standard CH
4
% by tapping the CH
4
box again. Note: 100% LEL is equal to 5% CH
4
.
CO
2
– Carbon Dioxide
CO
2
is measured via an infrared sensor. The measurement range of the sensor is 0-100% CO
2
.
O
2
- Oxygen
O
2
is measured via an electrochemical sensor. The measurement range of the sensor is 0 – 22% O
2
.
Balance Gas
Balance gas is a calculated value. It is calculated as follows:
Balance gas = 100%- CH
4
- CO
2
- O
2