Overview
ISO 22476-15:2016 - Measuring while drilling (MWD) is part of the ISO 22476 series on geotechnical field testing. It specifies technical principles, equipment requirements, execution and reporting for recording drilling parameters during geotechnical investigation drilling. The standard applies primarily to top-driven, destructive drilling methods carried out with fully hydraulically powered drill rigs and driving devices, and can also be used with core drilling. It does not cover recording parameters for soil grouting, installation of nails, anchors or piles.
Key topics and technical requirements
- Purpose and scope: Defines what drilling processes and applications are included and excluded for MWD in geotechnical investigations.
- Measuring systems and sensors: Requirements for sensors and data acquisition used to record drilling parameters such as hydraulic pressures, penetration length, flushing medium flow and pressure, rotation speed, torque, hammering energy, reflected vibrations and time.
- Drilling equipment: Guidance on selection of stable, adequately powered drill rigs, rods and bits suitable for achieving required borehole depth and stability.
- Selection of measured parameters: Identification of parameters imposed by method, set by the operator, and those reflecting ground response; and procedures to measure or calculate them.
- Test procedures: Preparation, positioning of the drill rig, drilling procedure, frequency of logging, registration of penetration length, equipment checks and calibrations, and test completion steps.
- Calculated and compound parameters: Processing of raw data to obtain penetration rate, down-thrust and net down-thrust, flushing medium pressure, drill-head torque, specific energies and other derived indices.
- Reporting and presentation: Requirements for reporting test results and recommended graphical presentation of drilling parameters (Annex B), plus applications guidance (Annex A).
Practical applications and users
ISO 22476-15 is used to:
- Provide objective, real‑time and recorded drilling parameter data for geotechnical site investigations
- Support interpretation of ground conditions alongside sampling and geophysical logs
- Improve quality control of destructive and core drilling operations
Typical users:
- Geotechnical engineers and site investigation specialists
- Drilling contractors and rig operators implementing MWD systems
- Manufacturers and integrators of drilling sensors/data logging systems
- Consultants preparing investigation reports and asset owners requiring standardized data
Related standards
- ISO 22476 series (Geotechnical investigation and testing - Field testing)
- ISO 22475-1 (Sampling methods and ground water measurements)
- ISO 14688-1 (Identification and description of soil)
- ISO 14689-1 (Identification and description of rock)
Keywords: ISO 22476-15, measuring while drilling, MWD, geotechnical investigation, drilling parameters, field testing, drill rig, hydraulic drilling, drilling sensors, penetration rate, down-thrust, flushing medium.