Close Interval Survey Planning
Counts stations, data points, wire-spool setups, and field days for a close interval survey.
Example
You enter
- Survey length (miles) 10
- Reading interval (ft) 2.5
- Readings per station (2 for on/off) 2
- Usable wire spool (ft) 5000
- Crew production (miles per day) 2.5
- Seconds per reading 1.5
- Crew day (hours) 8
- Test station spacing (miles) 1
- Alternative interval (ft) 5
You get
- Stations read 21120 stations, 42240 potentials
- Data points 42240
- Against test stations alone 11
- Readings between stations 21109
- Wire spool setups 11 reconnections to a test station
- Field time 4.0 crew-days
- Actual reading time 8.8
- Meter busy (%) 27.5
- At the alternative interval 10560
Details, formula, and sources
Ten miles at 2.5 ft is 21,120 stations against 11 test stations, and the meter is busy only 28% of the field time. Doubling the interval steps over half the holidays.
stations = length / interval, doubled for on/off; spool setups = length / spool, rounded up; field days = length / production rate.
NACE SP0207 (now AMPP) governs close interval survey practice.
Public planning arithmetic.
Estimate. AHJ and licensed professional govern.
Field names used by the API: survey_length_mi, reading_interval_ft, readings_per_station, spool_length_ft, production_mi_per_day, seconds_per_reading, crew_day_hours, test_station_spacing_mi, alternative_interval_ft, reading_count, data_points, test_station_readings, readings_between_stations, spool_setups, field_days, reading_hours, meter_busy_pct, alternative_reading_count
- Field time scales linearly with interval here, which overstates the saving since walking does not shrinkspec-v1772 caveat
- Crew day entered; the meter-busy share depends on itfield practice