16.03.2019 Views

CFSE - Certified Functional Safety Engineering I - Participant's Notebook - Exida 2007

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

SIF Verification Task<br />

<strong>Safety</strong> Requirements<br />

Specification:<br />

<strong>Safety</strong> Requirements<br />

including SIL target<br />

I Manufacturer <strong>Safety</strong> Manual I I Failure Rate Database I q Reliability I <strong>Safety</strong> Calc.<br />

j<br />

11. SIF Conceptual Design<br />

PFDavg,<br />

RRF<br />

MTTFS,<br />

SIL achieved<br />

/}<br />

0<br />

Copyright exida.com LLC 2001~2008<br />

55<br />

[ SIF Design Options l<br />

If the SIF verification shows that the SIL<br />

level has not been achieved by the<br />

proposed design a number of options<br />

are available to the designer:<br />

1' Re-evaluate the SIL requirement by<br />

adding other layers of protection, etc.<br />

2. Reduce the proof test interval -this<br />

may involve provisions for on-line<br />

testing.<br />

3. Choose equipment with better safety<br />

ratings- lower dangerous failure rate<br />

or better diagnostics.<br />

4. Change the architecture by adding<br />

more redundancy.<br />

4t~>

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!