Introduction to Modern Product Development - Advanced Design and Manufacturing Technologies for Biomedical Devices - page 15

available with the general function and all the sub-functions involved in the
product s proper working, all of which must be checked. The different functions

and sub-functions are checked one by one, thinking of how they could fail and
searching out any possible faults and then looking for the possible causes and
disturbances that could lead to those faults. When any possible causes of faults
have been assessed, countermeasures are designed for each one. If necessary, the
concept is redesigned, the design is improved or the procedures for manufacture,
assembly, logistics, quality, maintenance and others are modifi ed. As the work
required to complete a fault tree for an entire product is considerable, this method
is usually limited to decisive issues and critical processes. It is advisable for
designers to make this way of working part of their everyday activities and so
apply these concepts almost by intuition.
• “FMEA method (failure mode and effects analysis)” - This method, originally
designed for the “Apollo” program, is more powerful than the fault tree since it
quantifi es the absolute importance of every fault mode by using the so-called
RN, risk number, which is quantifi ed according to the probability of fault occur-
rence and the probability of its being detected. Therefore, risks can be classifi ed
in order of importance and priorities set for searching for and executing counter-
measures. It is widely used nowadays in all industrial sectors. However, the use
of this method requires expert staff in all departments. The “FMEA” is usually
reviewed several times during product design and possible countermeasures,
responsible persons and control dates are set. This method helps ensure the qual-
ity but above all the safety of the product right from the design stage, which has
previously proven to be of great help in fi elds such as machine design (Muñoz
Sanz et al. 2007 ).
• Quality meetings - Specially designed to avoid diffi cult-to-solve faults in the
advanced stages of development. The starting point is usually a check list based
on questions concerning the experience of previous designs. Members of all
departments usually take part in these meetings where countermeasures are sug-
gested and persons are proposed for being responsible for applying the measures
in the set timeframe. Once again, it is essential to emphasise the importance of
fl uid communication between all those involved in the product design process if
a successful outcome is to be reached.

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Additional tools for ensuring quality include several standards, which provide sys-
tematic descriptions of methodologies for direct application. Among such standards it
is important to cite the ISO 9000 family for quality management, the ISO 14000 and
19000 families for quality audits and environment, the OHSAS 18000 standards on
security and health and the ISO 28000 family on supply chain quality.
In the Biomedical fi eld, quality and security insurance are intimately linked to
assessing the effectiveness and risks related to a novel device, including aspects
such as biocompatibility testing, as introduced in Chap. 2 , detailed in Chap. 1 5
and incorporated to the global biodevice development systematic methodology
described in Chap. 17 .