terminology: you are referring to a "water level" and not a manometer, though the principle is similar.

Just curious:
What is the industry standard on how to conduct this measurement?
What is the calibration procedure?
Storage of the equipment? Operating temps?
Temp. compensation?
What liquids/ dyes are acceptable?
What slope over what distance is acceptable or unacceptable?
How do you measure for an undulation or "belly" btw points?
How do you account for unstable soil conditions?
What is the accepted standard deviation for this measurement according to AIA Stds.?
What are you using for reference points? The finished floor, top of foundation wall, soffit, etc?
Who is requiring this measurement?
Does your liabiliy insurance cover you for this sort of measuring/ testing?
With one person, who holds the other end?
Do you read the top or bottom of the meniscus?

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