GSAB – Global Standard Accreditation Board provides independent and impartial accreditation to Time & Frequency Calibration Laboratories in accordance with ISO/IEC 17025.
Our accreditation process ensures laboratories demonstrate technical competence in time and frequency measurement, validated calibration methods, reliable measurement results, and internationally traceable standards to the SI unit of time (second).
What Do Time & Frequency Calibration Laboratories Do?
Time & Frequency calibration laboratories calibrate and verify instruments that measure or generate time intervals, frequency, and synchronization signals. They ensure:
-Accuracy of frequency standards and oscillators
-Stability and drift performance over time
-Time interval measurement accuracy
-Synchronization with national or international time scales
-Measurement uncertainty estimation
-Traceability to primary time standards
These laboratories provide critical support where precise timing and frequency control are essential for safety, communication, and system integrity.
Industries supported include:
-Telecommunications
-Broadcasting & Satellite Communication
-Aerospace & Defense
-Power Generation & Grid Synchronization
-IT & Data Centers
-Research & Scientific Institutions
-Navigation & GNSS-based systems
Typical Time & Frequency Calibration Services Performed
Depending on their scope, laboratories may conduct:
-Frequency counter calibration
-Frequency generator calibration
-Signal generator calibration
-Oscillator calibration (quartz, rubidium, cesium standards)
-Atomic clock verification
-GPS/GNSS disciplined clock calibration
-Time interval counter calibration
-Stopwatch and timer calibration
-Time synchronization system verification
-Phase noise measurement
-Stability and Allan deviation analysis
-1 PPS (pulse per second) signal verification
-Network time protocol (NTP) and precision time protocol (PTP) validation
GSAB verifies that calibration methods are technically validated, traceability is established to recognized primary time standards, measurement uncertainty is properly calculated, and environmental influences are controlled.
Who Can Apply?
Time & Frequency calibration accreditation is suitable for:
-Independent calibration laboratories
-National metrology laboratories
-Telecommunications service providers
-Defense and aerospace laboratories
-Research institutions and universities
-Broadcasting and satellite service providers
-Industrial calibration service providers
Accreditation Criteria
GSAB accredits Time & Frequency calibration laboratories based on:
-ISO/IEC 17025
-Applicable ILAC mandatory documents
-National and international metrology guidelines
-Sector-specific regulatory requirements (where applicable)
Accreditation confirms:
-Technical competence of personnel
-Validated time and frequency calibration procedures
-Proper reference standards (atomic clocks, GPS standards, frequency references)
-Measurement uncertainty estimation and documentation
-Environmental control and electromagnetic interference management
-Equipment stability monitoring and drift analysis
-Participation in inter-laboratory comparisons
-Risk-based management system implementation
GSAB operates in accordance with ISO/IEC 17011, ensuring impartiality, technical rigor, and integrity in accreditation decisions.
GSAB follows a structured and technically rigorous accreditation process:
1. Application & Scope Definition
The laboratory submits a defined calibration scope including frequency ranges, time intervals, parameters, and declared Calibration and Measurement Capabilities (CMC).
2. Document Review
Evaluation of:
-Quality Manual
-Time & frequency calibration procedures
-Uncertainty budgets
-Traceability documentation
-Stability and drift monitoring records
-Proficiency testing or time comparison program participation
-Internal audit and management review records
3. On-Site Assessment
-Verification of reference standards and traceability chain
-Witnessing of live calibration activities
-Review of environmental and electromagnetic controls
-Assessment of personnel competence
-Evaluation of monitoring and data analysis systems
4. Corrective Actions & Technical Review
-Review and closure of nonconformities
-Verification of corrective action effectiveness
-Independent technical review prior to accreditation decision