Every piece of survey or testing equipment on a job site should be tracked with: equipment ID or serial number, calibration certificate date and next due date, current job assignment, and condition notes. An out-of-calibration instrument that generates failing grade checks or invalid compaction tests causes re-work and potentially invalidated as-built records. Systematic equipment tracking prevents this.
Why Equipment Tracking Matters
When an inspector or engineer reviews your as-built documentation, they will ask: what instrument was used for these measurements, and when was it last calibrated? If the calibration was expired at the time of measurement, the measurements may be rejected. On DOT and municipal projects, calibration documentation is a contract requirement, not optional.
Beyond calibration, tracking which instrument is on which job prevents the common problem of a grade checker showing up to a job with a different instrument than usual, entering the wrong parameters, and generating a systematic error that affects the entire day’s work.
What to Track for Each Instrument
| Data Point | Why It Matters |
|---|---|
| Equipment type and model | Inspector identification; specification compliance check |
| Serial number | Unique identification; matches calibration certificate |
| Last calibration date | Verify cert is current when measuring |
| Next calibration due date | Alert before using on a project where cert will expire mid-job |
| Current job assignment | Know where each instrument is; prevent scheduling conflicts |
| Condition notes | Track any known issues or recent impacts |
| Service history | Record of repairs that may affect accuracy history |
Calibration Requirements by Instrument Type
| Instrument Type | Typical Calibration Interval | Field Check |
|---|---|---|
| Rotating laser level | 12 months (factory) | Two-peg test every 3 months |
| Automatic level | 12 months (factory) | Two-peg test at start of project |
| Total station | 12 months (factory) | Check shot on known control |
| GPS/GNSS receiver | Firmware current; no traditional “calibration” | Check shot on known control before each project |
| Nuclear density gauge | Annual source certification + calibration block check daily | Calibration block check every use per ASTM D6938 |
| Pipe laser | 12 months (factory) | Grade display check before each setup |
Managing Equipment in Gradelog
Gradelog’s equipment registry tracks every instrument: model, serial number, calibration certificate date, and current job assignment. When you create a grade verification or compaction test session, you select the instrument from the registry — the equipment ID and calibration date are embedded in every as-built report automatically. If a calibration date is expired, Gradelog flags it before you start the session.
See also: Laser Level Calibration and Field Checks.