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CDOIF
Chemical and Downstream Oil
Industries Forum
CDOIF is a collaborative venture formed to agree strategic areas for
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benefits.
Guideline – Demonstrating Prior Use v4
Page 10 of 30
4.
DEMONSTRATING PRIOR USE
BS EN 61511 prior use requirements are based upon providing evidence that the
component has suitability for use in a SIF. In the case of field equipment this is achieved
by confirming extensive operating experience in an equivalent (or near equivalent)
process related system, which may or may not be safety related.
Non safety related data is comparable to safety related data only where the application is
similar in terms or duty and environment on both the wetted and non-wetted parts of the
component (for example process fluid characteristics [clean, dirty, viscous], temperature,
corrosiveness, indoor or outdoor service).
The level of detail required in the assessment should be in accordance with the
complexity of the component and with respect to probability of failure required to achieve
the required SIL of the Safety Instrumented Function.
In order to evaluate if a component can be considered for inclusion into a Safety
Instrumented Function based on prior use, and to provide the evidence, the following
requirements must be met:
•
The manufacturer of the component has a recognised quality management
system in operation (Refer to section 4.1)
•
The component has an identifiable specified functionality required for inclusion in
the SIF (Refer to section 4.2)
•
The component has been used before in an equivalent (or near equivalent)
process operation (which may be either safety or non-safety related) (Refer to
section 4.3)
•
The component has been used in sufficient volume to gain realistic and reliable
operating experience (Refer to section 4.4)
This demonstration of Prior Use suitability is an End User activity with respect to a
specific Safety Instrumented Function application.
4.1
Manufacturer’s quality, management and configuration management
systems
In order to assess the suitability of the component it is important that it is manufactured
by a manufacturer with a proven quality management system and product history. This
is important as any documented justification for the component to be classified as
suitable through prior use certain information will be required from or about the
manufacturer.
There are potentially three routes by which this aspect can be supported:
1. The Quality Management System
1
for manufacture of the component in question
has been independently verified by a third party certification body. This would be
supported by a third party certificate verifying compliance with relevant standards
such as ISO 9001.