Skip to content
EDWartens UK

Free course · Safety

Safety Instrumented Systems and SIL to IEC 61511

The protection layer that acts once control has already failed: why the SIS is kept apart from the BPCS, safety instrumented functions written with a trip point and a safe state, LOPA and the SIL target, PFDavg arithmetic, sensors, logic solvers and shutdown valves, de-energise against energise to trip, bypass and MOS discipline, 1oo2 and 2oo3 voting, common cause failure, the safety requirements specification, application programs, validation, proof testing and repair deferral.

See the modules

Free to learn. Verifiable certificate £19 when you pass the final exam (optional, VAT included).

Level
Advanced
Modules
15
Video
16 hours
Price
Free

Outcome

What you will be able to do

Explain why a safety instrumented system is kept independent of the control system; write a safety instrumented function with a trip point, a safe state and a response time; follow a LOPA to a SIL target and check it against a PFDavg calculation; choose a voting architecture from the SIL target and the cost of a spurious trip; find the common causes that quietly defeat redundancy; read a safety requirements specification and name what is missing; plan a validation test and a proof test that actually finds dangerous undetected failures; and run bypasses, overrides and repair deferrals with a record that stands up to an audit.

  • Say in one paragraph why a safety instrumented system is kept independent of the basic process control system
  • Write a safety instrumented function with a trip point, a safe state and a response time a designer can build from
  • Follow a LOPA to a SIL target and check it with a PFDavg calculation and a proof test interval
  • Choose between 1oo1, 1oo2, 2oo2 and 2oo3 using the SIL target and the cost of one spurious shutdown
  • Find the shared impulse lines, supplies and procedures that defeat redundancy, and read a safety requirements specification for what is missing
  • Plan a validation test and a proof test, and run bypasses, overrides and repair deferrals with an auditable record

Software

None required.

Hardware

None required. Access to a plant P&ID and a cause and effect chart makes the practice tasks real.

Syllabus

15 modules

Each module has video lessons, notes and a short quiz. The final exam closes the course.

  1. 1Why a plant needs a safety layer4 lessons
  2. 2BPCS, SIS and the safety instrumented function3 lessons
  3. 3Functional safety, IEC 61508, IEC 61511 and LOPA3 lessons
  4. 4PFD and the reliability arithmetic behind SIL3 lessons
  5. 5The SIS loop end to end4 lessons
  6. 6Trip philosophy, fail-safe design and overrides4 lessonsLab
  7. 7Redundancy, voting and safety architecture3 lessons
  8. 8Common cause failure and how SIS equipment fails4 lessons
  9. 9The safety requirements specification4 lessons
  10. 10SIS design and the documents it produces2 lessons
  11. 11The application program in the safety logic solver3 lessons
  12. 12Validation, verification and the SIS work process4 lessonsLab
  13. 13Proof testing instruments and valves4 lessonsLab
  14. 14Maintenance, repair deferral and engineering practice4 lessons
  15. 15Final assessment0 lessons

How it works

How this course works

  1. Watch the video lessonsOne module at a time, at your own pace.
  2. Take the module quizA short quiz at the end of each module shows what stuck.
  3. Keep your notesWrite in My notes beside each module and ask the trainer if you are stuck.
  4. Practise in the labOptionalTry a task from the module in the EDWartens Lab, in your browser.
  5. Sit the final examPass it once you have been through the modules.
  6. Certificate, if you want oneOptionalPaid, and only after you pass. Anyone can check it online.

EDWartens Lab

Practise this in the EDWartens Lab

Calibrate a 4 to 20 mA transmitter, tune a level or flow loop and read the trend in the Lab's process simulator.

Works alongside Safety Instrumented Systems and SIL to IEC 61511. The Lab is process control practice in your browser: no install, no hardware, free to use. Sign in as a learner and it opens with your account.

Open the free lab See the Lab
Process control: Tune a real process loop.

Levels to try with this course

Optional. Skip it whenever you like: it never blocks your progress or your certificate.

Why practise in a lab

Technical work is judged on what you can do: wiring, commissioning, finding a fault. Doing a task yourself teaches more than watching it a second time, and a lab lets you try it safely before you meet real equipment. It does not replace working on real hardware.

  • Practise safely, so a mistake costs nothing.
  • The lab checks your work like a site test, so you know when it is right.
  • Free, in your browser, with nothing to install.

Certificate

An optional certificate when you pass

Learning is free. Pass the final exam and you can have a certificate for £19, including VAT, with a number employers can check online. It records that you completed a free online course; it is not a regulated qualification or a CPD certificate.

  • Your name, the course, its study time and your final exam score
  • A unique certificate number and a QR code to its verification page
  • Issued by Wartens Ltd; add it to your LinkedIn profile in one click
  • Pay now or after you pass: it is issued the moment you pass the final

How the certificate works

Sample certificate for Safety Instrumented Systems and SIL to IEC 61511

Credits

Who made the lessons

The video lessons belong to their creators. EDWartens wrote the study plan, notes, quizzes and the final exam.

  • Instrumentation Tools

    the Safety Instrumented System training playlist, which supplies every video lesson in this course, from BPCS against SIS through LOPA, SIL and PFD to voting, the SRS, application programs, validation, proof testing and maintenance

Questions

About this course

Is the course really free?
Yes. Every module, practice task and assessment. You create an account so your progress is saved and the assessments can be marked. The certificate is the only paid item, and only if you want it.
What certificate do I get?
An EDWartens Certificate of Completion, issued when you have finished every module and passed the final assessment at 60 percent, with a verification code anyone can check. It is not a vendor credential and is never described as one.
Is this the same as a TUV or exida functional safety engineer certification?
No, and it is not equivalent to one. Those are paid, examined certifications awarded by certification bodies and they have their own fees, syllabus and eligibility rules. This course is preparation: it teaches the subject those exams are built on, so you arrive knowing the material rather than meeting it for the first time in a classroom.
Who made the video lessons?
Instrumentation Tools, on their own YouTube channel, credited in the Credits block at the foot of this page. EDWartens did not make the videos and the creator is not affiliated with EDWartens. What EDWartens wrote is the study plan, the notes, the practice tasks and the assessments.
What should I know before starting?
PLC or DCS basics and some field instrumentation experience. You should be comfortable reading a loop drawing and know what a transmitter, a solenoid and a shutdown valve do. Any of the free PLC or DCS courses on this site is enough of a foundation.
Do I need any software, hardware or a licence?
No. There is nothing to install and nothing to buy. If you can get hold of a P&ID, a cause and effect chart and a few SIS work orders from a plant you know, the practice tasks become much more useful, but the course works without them.
Does the course cover HAZOP?
No. It starts where the hazard study leaves off. LOPA, SIL determination, the SIL target and everything downstream of it are covered in full, but facilitating a HAZOP is a separate skill and this course does not teach it.
Who is it for?
Instrumentation, control, DCS and maintenance engineers in refineries, petrochemicals, chemicals, fertiliser and gas processing, EPC design engineers working on ESD and fire and gas packages, and instrumentation graduates who want to move towards the safety systems group rather than stay on general loop maintenance.

The Professional Module is five live days of Siemens PLC, HMI and SCADA with an instructor, then a resume session and a CPD certificate.

See the Professional Module