- The term "ergonomics" is interpreted broadly in the study and treated as equivalent to the term "industrial science" (incl. occupational health and safety) as far as content is concerned. It refers not only to the design of technical products, workplaces etc. in accordance with given human characteristics, but also to the aspects work and work organisation.
- The study assesses and systematically processes the current range of European standards containing definitions, ascertainments and statements concerning ergonomics (hereafter referred to as "ergonomic standards") (see point 4.). In addition, the areas of ergonomics in which there is a possible need for standardisation are presented. Standards were classified with the help of key words; this did not take account of whether or not the standards' statements in terms of content meet the technical requirements of ergonomics (e.g. with regard to completeness or accuracy).
- The results obtained can be used in a number of ways. The main areas of emphasis are as follows:
- to provide information about standards with ergonomic relevance using an information system which can be searched through by subject and statement forms,
- to point out gaps which can possibly be filled with the help of further regulations (need for standardisation) provided that this appears useful in view of the spirit of the "German Consensus Statement" on European standardisation,
- to find areas containing repeated mentions,
- to consult information for ergonomic design and for assessing work equipment, workplaces and working environments.
- In this way, the information system provides a useful addition and extension to the PERINORM data bank, the general information system for standards, in the field of ergonomics
Analysis system, method
The European standards relating to ergonomics - including draft standards and several standard proposals - which were available by the qualifying date (1.8.95) were analysed and organised with the help of a two-dimensional classification system according to their thematic dimension (in the three areas working conditions, effects and human characteristics) and their statement (e.g. terms and definitions, protection and design objectives, test methods, measuring and sampling procedures).
The German Consensus Statement was included in the classification system in order to find out in which areas standardisation can be regarded as problematic due to the fact that it is subject to the binding regulations of the member states. This revealed that criteria in the annex of the German Consensus Statement can be interpreted in different ways. Accordingly, categorisation in the classification system is variable. The means of categorisation used in this study should therefore be conceived as a basis for discussion and/or work. Resulting contradictions and uncertainties could result in further development of the German Consensus Statement.
The list of standards presented in the "Ergonomics" section of the DIN catalogue does not provide a comprehensive picture of ergonomics standardisation in the spirit of this study. The majority of European standards to be found there have the word "ergonomics" or "body measurements" in their title (e.g. ENV 26385 "Ergonomic principles of the design of work systems", EN 28996 "Ergonomics; determination of metabolic heat production"). Conversely, not all standards with the words "ergonomics" or "ergonomic" in their title are allocated to this section.
A search profile combining suitable industrial scientific and ergonomic terms was developed and researched in PERINORM. Of the around 1200 European standards (EN and EN ISO), including drafts, traced in this way, around 250 standards were accepted as being relevant to ergonomics following an assessment of content and were included in the classification system. As far as their titles were concerned, some of the ergonomic standards discovered did not appear to have anything to do with ergonomics.
Structure and content of standards
One of the key results of research is an indication that basic or generic standards and a suitable system are largely lacking. By contrast, in the field of machinery there is a structured set of standards clearly divided into generic A and B-type standards and machinery-specific C standards. In this case, B standardisation could deal with the ergonomic machinery requirements in general, especially as the Machinery Directive definitely calls for ergonomics or ergonomic principles to be observed. Due to the lack of comprehensive ergonomic B standardisation, the subject of ergonomics is, in some cases, dealt with in C-type standards which therefore contain mostly specific questions.
Examples of structural shortcomings
It is often unclear on what requirements in standards relating to human characteristics are based. In other words, it is not made clear whether values can be scientifically justified, if they were evaluated based on tests carried out with the help of workers, fixed more or less arbitrarily or not derived from human characteristics at all, despite the fact that this would have been appropriate in certain cases (e.g. EN 441-2 "Refrigerated display cabinets").
- Due to a lack of generic standards, basic requirements are dealt with in individual C-type standards (e.g. prEN 474-1 "General requirements - operator's seat") or divided between a number of different standards (e.g. human resistance levels or temperatures of touchable surfaces in EN 563, prEN 461, prEN 521), which could be grouped together at a single point.
- While repetition is avoided in sections on machinery by referring to generic standards, C-type standards in other areas, which can be assigned to the same design area, often contain the same or only slightly modified ergonomic considerations (e.g. EN 140).
All three clauses of prEN 894 "Ergonomic requirements for the design of displays and control actuators" and both parts of prEN 50099 "Principles for indicating, operating parts (control actuators) and marking" deal with terms and definitions. A separate clause on "definitions" or listing terminology in the first part of each standard would improve clarity and prevent definitions from being repeated.
- Requirements which do not refer to a single design feature only (e.g. temperatures for "touchable surfaces" in prEN 521) should be laid down in a more general, generic standard.
A good example of lacking coordination within standards is prEN 711 "Inland navigation vessels - Railings for decks - requirements, types". This includes, for example, different dimensions for the height of the railings in passenger and working areas.
In many of the standards classified in the study, the ergonomic requirements are not understood or distinguishable as such. In some cases, no reference to ergonomics is apparent at all, in others there are direct references to ergonomics at several points. By contrast, in the case of other equally ergonomic requirements in the same standard, no reference is made to ergonomics.
During research, errors were found in many draft standards which can be attributed to the translation; there are fewer errors in the final versions. Translating errors occur above all when technical terminology and colloquial speech use identical words with different meanings (e.g. in EN 60204-1 "grip" does not mean "Handhabe", but "Stellteil" or "Griff"). A trilingual version of a standard with a list of terms with the same meaning (e.g. in ENV 1070) could help to avoid similar errors.
- DIN EN 25353 "Earth-moving machinery", a C-type standard, contains information on the seat index point which is also necessary for other machinery without making this clear in its title or the descriptors.
- The Technical Committee CEN/TC 151 on "Machines for the building and building material industries" deals with ergonomic design in three standards (prEN 474-1, EN ISO 6682, EN 25353) without mentioning it explicitly. Standard EN 60900 on hand-guided tools deals with ergonomics in content without mentioning it by name.
Many standards contain statements on the category "stress resistance" without defining what individual stress resistance levels actually mean. An indirect definition is provided by stating stress resistance values, but stress resistance is not standardised explicitly.
Gaps in ergonomic standardisation
Not all areas of the classification system have been filled with standards relating to ergonomics. An empty section of the classification system, in other words the lack of European standards in a certain area, is considered a "gap" in the ergonomic standards system. A gap is described as a "deficit" if there is need for regulation (see 2.). The following standardisation gaps are given a special mention in the study:
- Individual standards deal with requirements for special tools. There is a lack of general requirements made of the ergonomic design of tools in a generic standard.
- The ergonomic design of work equipment in the field of "Agricultural and forestry machinery" contains gaps.
- There are no European standards on the design objects "Skin protection" and "Waistcoats, jackets".
- No ergonomically related standards could be assigned to the design object "Textiles"; however, in some cases requirements are made of the materials used for personal protective equipment which could also refer to textiles (e.g. no skin irritation).
- There is no definition for "physical strength" in the section on "human characteristics".
- As far as "stress resistance" is concerned, statements are often made about a certain stress resistance without providing a guide value for an acceptable stress resistance level. Measuring methods for stress resistance in the "human characteristics" design are only standardised for "body measurements" and "Ergonomics; determination of metabolic heat production" (EN 28996).
- KAN endorses the results of the study and has decided to publish them as a KAN report. KAN shares the authors' opinion, namely that the term ergonomics does not only refer to the design of technical products, workplaces etc. in accordance with given human characteristics, but also to the aspects work and work organisation. Standards containing definitions, ascertainments and statements concerning ergonomics in this sense are considered here as "ergonomic standards".
- The KAN report is being published for two target groups in particular:
Need for DIN to take action
- to inform the standardisers about the ergonomics standardisation which covers many different specialist areas,
- to inform designers and those people and institutions responsible for industrial design and occupational health and safety about existing ergonomic standards on which ergonomic design and the assessment of work systems (work equipment, workplaces, working environment) can be based.
KAN is to make the "Ergonomic Standards" data bank available to DIN thereby offering its committee "ergonomics" (FNErg) the chance to pursue standardisation in the field of ergonomics, which is divided up among a number of Technical Committees. DIN is requested to continue to add to and update the "Ergonomic Standards" data bank. KAN offers to make the "Ergonomic Standards" data bank accessible to the user via the "PERINORM" CD or on the Internet. If DIN does not accept this offer, the KAN secretariat is to demonstrate other means of distribution in discussion with DIN.
KAN recommends that DIN analyse the data bank of the "Kommission Sicherheitstechnik" on standardisation projects related to occupational health and safety and other internal DIN information which makes it possible to establish which standards bodies apart from FNErg, CEN/TC 122 and ISO/TC 159 operate ergonomics projects. According to KAN, by optimising the flow of information between standards bodies it is possible to control standardisation activities even more closely, at the same time improving the way in which scientific results are converted into ergonomic standards.
Safety-related B-type standards for completing the Machinery Directive must set practical, concrete guide values for stress, taking account of the German Consensus Statement in accordance with the needs of C-type standardisation.
Similar to the way in which safety standards for the Machinery Directive are divided into A, B and C-type standards, ergonomic standards for special design objects (e.g. industrial sewing machines) should also be distinguished from those that are too general (e.g. noise levels, basic design principles, control actuators). A typology of the ergonomic standards based on machinery standardisation is recommended since this would make it easier to structure the ergonomic standards and the search process. In this context, CEN/BTS 4's suggestion of dividing ergonomic standards into "Generic standards", "Application standards" and "Products standards" is supported by KAN. All ergonomic standards in the field of "Personal protective equipment" could then be assigned to "Products standards" and the human characteristics given in these standards could be combined in a "Generic standard" (an anthropometric data atlas or a collection of guide values for acceptable stress to which people can be subjected). As far as this type of standardisation project is concerned, the way in which human characteristics are divided up in the study could serve as an classification criterion.
KAN recommends the following structural improvements:
Taking account of the fact that in European standardisation ergonomic standards have so far been prepared by at least 74 different standards bodies, KAN believes that it is essential for FNErg and CEN/TC 122 to develop a guide for drawing up ergonomic standards which allows other standards bodies to coordinate the contents of their work. This includes consideration of
- combining human characteristics and ergonomic requirements in generic standards,
- (source) information or at least explanations in informative annexes on the derivation of the human characteristics dealt with in the standards,
- presenting the connections between ergonomic requirements and the human characteristics on which they are based,
- disseminating a general opinion of the term "ergonomics" as perceived by this study, especially with regard to the allocation of headwords in PERINORM.
In this way, FNErg, CEN/TC 122 and ISO/TC 159 would take on a coordinating role which is yet to be perceived.
- anthropometric data specific to sex and dependent on age,
- parts of the population (percentiles) for whom the design and dimensioning of products is intended and
- combined stress.
KAN considers it necessary for FNErg and CEN/TC 122 to compile a trilingual terminology standard for general definitions in the field of ergonomics which would help to produce better coordinated and structured ergonomics standardisation and improve the quality of translations of standards.
KAN requests DIN to support the follow-up project "Ergonomics - status review of ISO and DIN standards as a continuation of the KAN study 6/94" by means of active participation.
Need for the KAN secretariat to take action
In the form of the "Ergonomic Standards" data bank, the study has provided an instrument which makes it possible to identify standards which, as far as the "German Consensus Statement" is concerned, can be categorised as problematic. The KAN secretariat is instructed to test and develop this identification procedure in the implementation of the KAN study "Standardisation in the field of health and safety at the workplace" (KAN Report 2).
The KAN secretariat is instructed to consult DIN to make sure that the ergonomics data bank is made available to the target groups listed at point 2.
The KAN secretariat is instructed to address the problems mentioned at point 5. concerning setting guide values for ergonomic stress in the field of product standardisation based on the German Consensus Statement so that the KAN committee for "Standardisation in the field of directives based on Article 118a of the EC Treaty" can determine its position on this matter.