Issue 41 – August 2012
Electroheating, the high-power heating of a range of materials using electrical energy with specialist equipment, is widespread in industrial applications. However, a different kind of electroheating, designed for smaller tasks, requires portable electric heating tools, such as soldering irons for metals and plastics, paint strippers, or glue guns. The safe operation of these tools is very important as they are widely used globally in domestic and professional environments. A new consolidated Standard, IEC 60335-2-45 Ed. 3.2 b(2012) Household and similar electrical appliances – Safety – Part 2-45: Particular requirements for portable heating tools and similar appliances, ensures this is the case. The consolidated version consists of the third edition (2002), its amendment 1 (2008), and its amendment 2 (2011).
From hobbyists to professionals
Portable heating tools are now available for all sorts of tasks: glue guns often replace conventional adhesives, while paint strippers and soldering irons for metals and plastics are used by do it yourself enthusiasts, hobbyists, and professionals in wide-ranging applications. Since they are not being deployed in an industrial environment where there are specific protection measures, they need to meet stringent safety requirements.
International Electrotechnical Committee (IEC) technical committee (TC) 61 prepares Standards for safety requirements primarily for household purposes, but also for other equipment and appliances in similar fields where there is no IEC TC in existence. This means that it develops Standards for portable heating tools. Earlier this year IEC TC 61 published a consolidated version of IEC 60335-2-45.
Wide range of appliances
IEC 60335-2-45 applies to portable electric heating tools and similar appliances with a rated voltage not exceeding 250 V. It also covers appliances not intended for normal household use, but 'which nevertheless may be a source of danger to the public, such as appliances intended to be used by laymen in shops, in light industry, and on farms'.
The Standard deals with the common hazards presented by appliances in and around the home and assumes these tools are being operated by suitably qualified and experienced persons. The Standard does not apply to appliances intended exclusively for industrial purposes, those intended to be used in locations where special conditions prevail – such as the presence of a corrosive or explosive atmosphere – or to arc-welding equipment. In all these cases, other Standards apply.
Examples of appliances covered by IEC 60335-2-45 include:
- branding tools for marking wood, leather, and other materials
- burning-in pens used for marking on wood, leather, and other materials by means of a heated tip
- conduit-soldering tools used for joining metal piping by means of solder
- firelighters for igniting solid fuel such as charcoal or wood
- heat guns and appliances that produce a jet of hot air
- household film-welding appliances
- paint strippers for softening paint using hot air
- soldering irons with a heated tip for soldering
- thermoplastic conduit-welding tools – appliances for welding conduits by partly melting the thermoplastic material of a separate fitting.
As can be inferred from this non-exhaustive list, the range of application for portable heating tools is extremely wide and covers use by laypersons, so the provision of proper markings and instructions is essential.
Multiple environments – multiple risks
Unlike environments where equipment such as industrial tools is used by trained personnel and where specific safety conditions are generally in force, portable heating tools may be used by individuals with insufficient training.
This means that appropriate and specific safety provisions and test conditions must be set for these appliances even if IEC 60335-2-45 also recognises the internationally accepted level of protection against hazards including electrical, mechanical, thermal, fire, and radiation of appliances.
To ensure these tools are as safe as possible to use, special attention must be paid to many aspects of that use. They include:
- protection against access to live parts
- power input and current
- moisture resistance
- abnormal operation
- stability and mechanical hazards
- mechanical strength
- construction, including internal wiring, components, supply connection and external flexible cords, terminals for external conductors or provision for earthing
- resistance to heat and fire
- resistance to rusting
- radiation, toxicity, and similar hazards.
As these tools and appliances are used in all countries, national or regional differences and additional conditions required by various health and safety authorities may apply.
TC 61 decided that this Standard will remain unchanged until its 2014 stability date when it could be reconfirmed, withdrawn, replaced by a revised edition, or amended.
The range of safety issues taken into account, as well as the continuous additions and improvements made by TC 61 experts to this Standard, combined with the needs of users for such appliances, mean IEC 60335-2-45 will not be withdrawn but remain relevant and essential in the future for the manufacturers of portable heating and similar appliances.
IEC 60335-2-45 is to be read in conjunction with IEC 60335-1:2010.
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Summarised from IEC's e-tech, July 2012.