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1.6.3 Simple Calculation Check

Arithmetic checks (necessary for checking the reduction)

∑ BS - ∑ FS = ∑ Rise - ∑ Fall = Last RL – First RL

1.6.4 Actual and Allowable Misclosure (accuracy in levelling)

Allowable misclosure = ± 5 √N mm, where N is the Number of Instrument

Positions which is the same as Number of BS readings.

If actual misclosure > allowance misclosure, levelling should be repeated If

actual misclosure < allowance misclosure, misclosure should be equally

distributed between the instrument positions

9 | Soil Engineering Practical Workbook