BS IEC 62841-2-1 AMD1. Electric motor-operated hand-held tools, transportable tools and lawn and garden machinery. Safety - Part 2-1. Particular requirements for hand-held drills and impact drills Ingestion-build-47182 ISO 14405-2 specifies technicalities for

ISO 14405-2 specifies technicalities for dimensional tolerancing such as related terms and definitions

the product category rules (PCR) section of this Technical Report recommends “state-of-the-art” process and data assumptions in order to reduce uncertainty

(Which gives terms and definitions) and you may also be interested in BS 8887-1 which is aimed at the design stage

It details best practices to minimize fatigue failure and prolong service-life of spur and helical gears

DD 183 also provides guidance on election of package size according to dimensions

BS IEC 62841-2-1 AMD1. Electric motor-operated hand-held tools, transportable tools and lawn and garden machinery. Safety - Part 2-1. Particular requirements for hand-held drills and impact drills Ingestion-build-47182 ISO 14405-2 specifies technicalities for