Overview
EN ISO 28927-8:2009/A2:2019 is a CEN-endorsed amendment to ISO 28927-8 that extends standardized test methods for evaluation of vibration emission from hand-held portable power tools. Amendment 2 specifically adds requirements and test procedures for oscillating knives (vibrating screen removal tools) used with rotary-driven blades that move in an angular reciprocating motion. The text was approved by CEN in January 2019 and is published in English, French and German.
Key topics and technical requirements
- New definition (Clause 3.1.6): defines an oscillating knife as a rotary-motor machine with a blade that moves with an angular reciprocating movement.
- Test specimens and examples: Figures updated (Figures 1–13, new Figure 13 for oscillating knife) and measurement-location diagrams added (e.g., Figure 26 for straight oscillating knives).
- Cutting test material: Two hard rubber square profiles, 20 mm and 35 mm thick, are specified for horizontal cutting tests.
- Feed force: Horizontal feed force during cutting must be (120 ± 12) N (force in direction of cut).
- Rubber hardness and conditions: Hard rubber specified as (57 ± 5) Shore A (ISO 868). Ambient/room and rubber temperature should be 23 °C to 26 °C.
- Test set-ups (8.4.2.5): Two alternative jigs are provided:
- a) Fixed jig where feed force is measured via a measuring platform on which the user stands (constant display of actual feed force).
- b) Jig with direct feed-force measurement and live display.
- Measurement practice: Vibration values must be identified separately for each machine + inserted tool (knife) combination due to variability of inserted tools.
- Duration and practical notes: Measurement duration at least 8 s. Mounted workpiece must have no resonances in the hand–arm frequency range. Ventilation or fume extraction is recommended because rubber cutting may produce smoke.
Applications and who uses it
- Manufacturers of oscillating knives, handheld saws and reciprocating tools - for product development, vibration reduction and labelling.
- Test laboratories and conformity-assessment bodies - to perform repeatable vibration-emission tests and generate comparable data.
- Health & safety engineers and ergonomists - to assess hand–arm vibration exposure and support risk assessments under machinery safety directives.
- Regulatory compliance teams - the standard supports presumption of conformity with relevant clauses of Directive 2006/42/EC where cited.
Related standards
- ISO 28927 series (Part 8) - broader test methods for saws, polishing and filing machines with reciprocating action and small oscillating/rotating saws.
- ISO 868 - referenced for Shore A hardness testing of rubber.
Keywords: EN ISO 28927-8:2009/A2:2019, oscillating knives, vibration emission, hand-held portable power tools, test methods, feed force, Shore A.