Overview
ISO 28927-7:2009 - "Hand-held portable power tools - Test methods for evaluation of vibration emission - Part 7: Nibblers and shears" specifies a laboratory, type‑test method for measuring hand‑transmitted vibration at the handles of power‑driven nibblers and shears. The standard defines how to establish vibration magnitudes in gripping areas under specified test conditions so results can be used to compare different models intended for cutting sheet metal or composite materials. It applies to tools driven pneumatically or by other means.
Key topics and technical requirements
- Purpose: Type‑test procedure to determine vibration emission from nibblers and shears (laboratory measurements at the handle).
- Measurement principles: Vibration measured in three orthogonal axes and combined into a total vibration value; measurements at primary hand positions (both hands when applicable).
- Transducer placement: Defined positions and orientations close to the hand (between thumb and index finger) to minimize operator disturbance; updated positions compared to previous standards.
- Instrumentation requirements: Specifications for transducers, mounting, frequency‑weighting filters, integration time, calibration and auxiliary equipment (see Clauses 7 and 9).
- Test conditions: Detailed operating and environmental conditions, sample preparation (supported sheet metal, good condition punches/shear blades), and operator arrangements for reproducible results (Clauses 8 and 9).
- Data reporting and uncertainty: Declarable vibration emission values, model test report format (Annex A), and uncertainty determination (Annex B). The standard notes that emission values below 2.5 m/s² should not be relied on to estimate workplace exposure without additional measurements.
- Reproducibility: Procedures intended to produce representative type‑test values comparable across models; emphasizes sources of variation (operator, task, material support, tool wear).
Practical applications
- Product evaluation and design: Manufacturers use ISO 28927-7:2009 to quantify and compare vibration performance of nibblers and shears during development and type testing.
- Compliance and declaration: Enables consistent declaration of vibration emission for technical specifications and safety documentation.
- Procurement and selection: Purchasing professionals and safety managers can compare models using standardized vibration data.
- Risk assessment guidance: Provides type‑test values that support, but do not replace, workplace exposure assessments performed per ISO 5349.
Who uses this standard
- Tool manufacturers and R&D engineers
- Test laboratories and certification bodies
- Occupational health & safety professionals
- Purchasing/specification engineers for industrial and metal‑working equipment
Related standards
- ISO 20643 - Principles for evaluation of vibration emission (basis for ISO 28927 series)
- ISO 5349 - Measurement/evaluation of hand‑transmitted vibration for workplace exposure
- ISO 2787, ISO 5391, EN 12096 - referenced for related terminology, tests and declaration/verification procedures
Keywords: ISO 28927-7:2009, vibration emission, hand‑transmitted vibration, nibblers and shears, hand‑held power tools, vibration measurement, type‑test, sheet metal cutting.