Ethical issues in engineering design - 3TU.Centre for Ethics and ...

Ethical issues in engineering design
The contents of the codes differ. The American ASME codes are low-stress
codes. The stresses permitted in the materials are low. This means that American
constructions are heavier. The ASME codes require little testing and few
inspections once the system is in use. The ASME code is extensive, and the rules
are very detailed. The European codes (BS, Merkblätter, Regels) are high stress
codes. They allow higher stresses in the materials. A construction will probably
be lighter using European codes, but regular inspections and tests during use are
required on an ongoing basis.
5.2.3 Standards regarding pressure vessels and pipes
Standards are designed to achieve compatibility and interchangeability [Hunter,
1995]. Most reasons to standardise measures, products and systems have
economic origins. In most countries there is a national standardisation
organisation, for example the American National Standards Institute (AINSI) and
NEN (Netherlands Standardization Institute). 3 A European normalisation
institute (CEN) exists for the European community. Worldwide the International
Standards Organisation (ISO) is preparing worldwide standards. Standards are
conventions that make trade between different companies and countries and the
application of spare parts possible. Standards are prescriptive and describe in
detail the hardware and conventions required for any item. Dimensions of certain
parts are exactly and unambiguously established in a standard as are conventions
on the technical drawing of an object. Standardisation ensures that a bolt
produced by a certain company will fit a screw produced by another company
provided that both companies use the same standard. Standards are usually not
enforced by legislation. Legislation can however, refer to standards. Codes also
often refer to standards.
Larger companies will have company standards, these company standards are
like national standards, conventions. These conventions can be about issues such
as what kind of pipe is used for which temperature and medium. Some
companies also have company standards that are conventions on good design
practice or conventions to design installations that are safe. Company standards
often refer to (international) standards and codes. As said before these company
standards are not part of the regulative framework. The regulative framework
only comprises the rules and guidelines that hold for all products of a product
type in a country or within Europe. The regulation sets the minimum required
safety level. Company standards can therefore only comply to, or be stricter than,
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3 The NEN formulates both codes and standards. The standards are primarily meant to lead to
interchangeability. The codes are used to guarantee levels of safety and quality, see also
section 6.3.
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