Safe and efficient electric tools

By Gabriela Ehrlich

For gardening and DIY (do-it-yourself), many of us use electric tools in and around the home. We expect not only that they will do the job at hand but also that they will work safely and reliably. IEC TC (Technical Committee) 116: Safety of motor-operated electric tools, has published International Standards that cover specific safety requirements for hand-held electric tools such as saws, drills, trimmers, sanders, hammers and spray guns as well as for hand-held motor-operated electric tools such as circular and other saws, threading machines, etc. They take into consideration the common hazards encountered in the normal use and (reasonably foreseeable) misuse of the tools and cover general and specific safety requirements so that we can be hands-on without taking our hands off as we work.

Cordless gardening tools. Source Bosch

Battery-operated cordless power tools

With the increasing popularity of battery-operated cordless power tools, the IEC International Standards prepared by IEC SC (Subcommittee) 21A: Secondary cells and batteries containing alkaline or other non-acid electrolytes, have an essential role to play. They provide the technical specifications and testing requirements that are needed to evaluate the safety and operating performance of the batteries used in these devices.

A cordless tool also has the advantage that it doesn’t need to be connected to the mains, except for recharging. This removes the risk of accidentally cutting through or damaging the power cord. However, dust and water can also harm the tool and put the user at risk. That’s why all new power tools are tested against IEC 60529, which rates their dust and water resistance using the IP (Ingress Protection) Rating code. The standard is prepared by TC 70: Degrees of protection provided by enclosures.

Additional safety measures are needed for tools that cut – for example, hedge trimmers. They usually require the user to press two contacts simultaneously, using both hands. If one of the contacts is released, the device stops. RCD (residual current device) sensors react to changes in the flow of electricity and are managed by IEC SC 23E: Circuit-breakers and similar equipment for household use.

Sensor-controlled robotic lawn mowers

Another area that depends strongly on IEC work concerns the electronic components that are part of a growing number of tools and devices. One example is the battery-powered robotic lawn mower. It has sensors that recognize when it is on grass that has to be cut and others that make it change direction when it reaches walkways or patios. Such a lawn mower not only needs high-quality electronic components to enable it to function reliably, its manufacturer also needs to prove that the device complies with hazardous substances requirements – for all of this, manufacturers look to IECQ, the IEC Quality Assessment System for Electronic Components.

bosch_cordless_tools_org Cordless gardening tools. Source Bosch
makita_cordless_jigsaw_org Makita lithium-ion jigsaw
203380fb-6c6f-4dbc-be0a-fb209a73fbb6_tradePrince Norman robot lawn mower. Source: Hangzhou Norman Innovation & Technology Co. Ltd.