Ensuring that safety footwear works

Investigating the growth of safety footwear standards and test methods.

by Peter Allen

In this first of a series of articles, we are considering SATRA test equipment which can be used to test safety footwear to the requirements of EN ISO 20345:2011 – 'Personal protective equipment – Safety footwear' and the associated method EN ISO 20344:2011 – 'Personal protective equipment – Test methods for footwear'. However, before looking at these standards in more detail, there is merit in gaining an overview of their origins.

The development of the bulk of safety legislation evolved over the last 200-250 years. In Europe, this initially came about as a response to the poor working conditions within industries which developed during the period of the Industrial Revolution. It was also in reaction to significant accidents resulting in loss of life – for instance, in mining or due to accidents involving steam boilers. Initially, the emphasis was on regulating the working conditions within factories and the safe operation of machines. However, with the evolution of health and safety legislation, regulations have also been introduced relating to the protective clothing and equipment worn by employees.

Regulating safety clothing

For many centuries, protective clothing has been worn by people working in trades, crafts and early industries, this use having evolved as a means of protecting the user from specific hazards. As an example, the use of heavy leather aprons by a range of trades – wooden clogs (or 'sabots'), worn in some parts of Europe – provided a degree of footwear protection. As health and safety legislation developed, it was recognised that there was a need to regulate safety clothing. In the last 50 years, this activity has accelerated.

Comprehensive legislation has developed, which affects a wide range of industry sectors and types of protective footwear, clothing and equipment. In many cases, this is related to the industrial activity in which the user is engaged and is focused on the risks to which the user could be subjected. In Europe, individual countries initially developed their own regulations. With the formulation of the European Union (EU), however, common legislation has been implemented – in many cases drawn from and developed from existing national legislation.

For safety footwear, the first EU standard replacing national legislation was EN345:1992 – 'Safety footwear for professional use'. This was superseded by EN ISO 20345:2004 – 'Personal protective equipment. Safety footwear' which, in turn, has evolved to EN ISO 20345:2011. Not all types of EU safety footwear are covered by this standard. Other standards have been developed for specific types of use, including EN ISO 20347:2012 – 'Personal protective equipment – Occupational footwear'. As in Europe, safety footwear standards were developed by individual nations in other parts of the world. There is, though, a growing trend for more counties to look to align their own safety legislation around ISO methods. As shown by the full title of the standard, EN ISO 20345 is also an International Organisation for Standardisation (ISO) method.

Updating the standards

These standards are reviewed after a period of five years, at which point proposals for revisions are invited. A revision of an existing joint (EN/ISO) standard takes place as a parallel revision by both parties. Within the European Committee for Standardisation (CEN – from the French, Comité Européen de Normalisation), a Technical Committee – CEN/TC161 – 'Foot and leg protectors' – is responsible for the development of safety footwear standards. This works in collaboration with ISO technical committee ISO/TC 94 – 'Protective clothing and equipment, Subcommittee SC3 Foot Protection'.

CEN/TC161 currently has three working groups responsible for methods, specifications and slip resistance. Project groups can also be established to address particular issues. The CEN/TC161 committee representatives are drawn from EU countries and receive input from national technical committees. For example, in the UK, this committee is formulated under the British Standards Institute (BSI). ISO members are drawn globally from participating nations.

Many of the tests which are specified within EN ISO 20344 were derived from existing general footwear methods. Others were developed specifically for testing safety footwear. What is contained in EN ISO 20345:2011? This standard specifies basic (mandatory) and additional (optional) requirements for safety footwear used for general purpose. It includes such aspects as mechanical risks, slip resistance, thermal risks and ergonomic behaviour.

Special risks are covered by complementary job-related standards (for instance, footwear for firefighters, electrical insulation, protection against chainsaw injuries, protection against chemicals and molten metal splash and protection for motorcycle riders).

After a section on initial definitions, including illustrating different types of footwear construction, the standard sets out two classes of footwear: I and II. Class I is footwear made from leather and other materials, excluding all-rubber or all-polymeric footwear. Class II is all-rubber footwear (that is, entirely vulcanised) or all-polymeric (entirely moulded) footwear.

Each class has requirements which are specific to the class, as well as others which are common to both classes. This is set out in tabular form within the standard. Hybrid footwear (such as with a polymeric lower section and a textile or leather upper section) is covered in Annex A to the standard.

The approach taken by the standard is to set out a 'basic requirement for safety footwear' (section 5) and 'additional requirements for safety footwear' (section 6). Subsections to these requirements are set out in tabular form and are classified under the following main sub categories:

• for section 5 – design, whole footwear, upper, vamp lining, quarter lining, insole/ insock, tongue and outsole
• for section 6 – whole footwear, upper and outsole.

Within each of these subsections, there are further subsections setting out detailed requirements. The ‘additional requirements for safety footwear’ are also set out in section 6, which also assigns a marking that can be associated with footwear complying with these demands. As an example, 'Whole footwear – Water resistance' is marked 'WR', whereas 'Upper – Water penetration and absorption' is marked 'WRU'.

All safety footwear sold in or into the EU needs to be CE marked. Most fall in Category 2 ('intermediate') with some falling in Category 3 ('complex'). Firefighters’ boots are, therefore, in this latter category.

Development of SATRA footwear tests

SATRA has a long track record in conducting fundamental research and producing test methods. Since its establishment in 1919, SATRA has developed over 400 test methods, the majority relating to the footwear and leather goods industries. Many SATRA test methods have been adopted into national legislation and then into EU or other national regulations. SATRA has contributed to and continues to contribute to the development of EU standards, and has a long track record in the testing and certification of safety footwear.

This is the foundation of SATRA test equipment which is designed and made by SATRA. SATRA designs and manufactures over 300 types of test machines, devices and accessories, which are sold to 70 countries worldwide. Some of these SATRA machines have been the basis of methods incorporated into the safety footwear standards – for example, the STM 603 slip resistance tester, which is the most widely used slip resistance tester in the global footwear industry and associated testing laboratories.

This article provides a background and introduction to EN ISO 20345:2011 and EN ISO 20344:2011. Future articles will feature SATRA test machines that can be used to conduct specific tests defined within these standards.

Click here for comprehensive information on SATRA's range of test equipment.

Publishing Data

This article was originally published on page 36 of the March 2016 issue of SATRA Bulletin.

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