WHAT IS FUNCTIONAL SAFETY?
Before jumping directly into the concept of Functional Safety, we will start with the concept of overall safety, which is simply defined as “freedom from harm”. It is the expectation of every human being, to have a safe environment. In order to achieve this, different means are employed. So we need to have a safe home, a safe work environment, a safe means of transport and so on. Safety by itself is a vast subject and there are various sub disciplines within it.
Where is Functional Safety used?
It is used in a variety of sectors, not just in industrial manufacturing plants. It is used in aircraft, buildings, machinery, railways, automotive- just to name a few. However different functional safety standards apply in different industry and business sectors. Here, we will learn more about applying functional safety in the manufacturing and allied industries, such as power generation, oil & gas, etc.
Functional Safety in process plants
In a manufacturing plant or facility, safety can be achieved in different ways. For example, we may reduce the risk of overflow of a day tank, by having an overflow pipeline that will divert the excess flow to another tank, located at a lower level. In this case safety is achieved purely by the right piping and the use of gravity. This can be considered an example of achieving overfill protection by mechanical means and using Process Safety principles.
However, we have an alternate way of achieving overfilling protection for the tank. Say, if we use control system elements like a level sensor switch, to detect the high level of liquid in the tank and then use it to solve logic to shut off an actuated valve on the inlet line, then this is an example of Functional Safety ( which depends on "Active Systems" and not passive systems). This is why we have the Functional Safety definition that says that it is a part of the overall safety of any system, that achieves safety by correctly responding to inputs automatically. This overfill prevention arrangement is an example of a typical Safety Function.
Take a look at the Functional Safety video below, which will make matters clearer.
When operators of this unit shown above use Personal Protection Equipment such as helmets, gloves or safety shoes, they are following principles of Occupational Safety.
In a nutshell, in a manufacturing plant, especially in the process industries such as Oil & Gas, Chemicals, Pharmaceuticals, Power generation, Nuclear and similar we achieve safety via Process Safety, Functional Safety and Occupational Safety. In case the plant or facility has materials that are flammable or explosive, then we also use principles of Hazardous Area management to ensure safety. In case the facility uses electronic systems Automation systems such as DCS or PLC or SCADA (basic process control systems) or a SIS (safety related system), then we also need to maintain cyber security of these systems in order to ensure overall safety.
Abhisam has online courses, workshops & consulting services on all the above areas. On this page, we will be only discussing Functional Safety, Safety Intergity Level (SIL) and and Safety Instrumented Systems. You can explore other pages of the Abhisam site to get more information on HAZOP, LOPA, Hazardous Area Classification, Industrial Cybersecurity, Personal Protective Equipment and similar related subjects.
Which Functional Safety Standards are important?
The IEC 61508 standard is considered as the mother standard in the world of Functional Safety. Other sector specific standards are based on this principal standard. IEC 61508 has seven parts, the first four are normative (means mandatory to claim compliance with the standard) and others are informative (just for information on how to meet the requirements of the standard). In the process industry IEC 61511 is the accepted international standard worldwide. The US uses ISA S84, but this is now almost identical to IEC 61511. In the automotive sector, ISO 26262 is the primarily accepted functional safety standard, whereas in the machinery it is IEC 62061. There is also an ISO functional safety standard for machinery, ISO 13849. In the railway industry there are three functional safety standards, EN 50126, EN 50128 and EN 50129- the entire set is based on IEC 61508.
There are other sector specific functional safety standards, such as IEC 61513 for the nuclear industry. Where no sector specific standard exists, we can use IEC 61508. However it must be noted that even a sector specific standard does reference back to the main standard IEC 61508, so we should have a good idea of both. For example, in the process industry, the safety instrumented functions are designed as per IEC 61511 (or ISA S84) but the devices used in these functions, such as sensors, transmitters, safety logic solvers, relays, final control elements such as actuators, all have to conform to IEC 61508.
Many times, engineers are focused only on hardware failures. However every functional safety standard, covers hardware failures, systematic failures (including software failures and management failures) and common cause failures for the safety function. If we are able to reduce all these three types of failures to a great extent, then we will have a good functionally safe system that is part of the overall safety of the plant. Our safety requirements must address all these types of failures.
The Safety Life Cycle approach
One of the main concepts of these standards, is their focus on the Safety Lifecycle. This approcah means that ensuring safety is not a one shot affair, but it must be present and match the entire lifecycle of the plant or equipment. This starts from the concept stage, then hazard and risk analysis, then deciding the safety requirements, then designing the safety functions (and also other means of risk reduction that contribute to overall safety), installation, validation, commissioning and finally decommissioning at the end of the plant or machinery life. In between, if there are any modifications, then these are also part of the safety lifecycle and some steps need to be done again.
Functional Safety Management
Management of Functional Safety is a very important part of the Safety Life cycle. Since the life period of a typical plant or an equipment can sometimes easily exceed 4--50 years, we need good management to manage the Functional Safety over the entire life of the asset. This is emphasized in all functional safety standards, be it IEC 61508 or ISO 26262 or any other. You may have the best safety functions & control systems designed and installed, but if you have poor management, then it may not really work over the life of the plant or equipment.
Where can I learn more about this?
Please see some useful functional safety training courses below.
Functional Safety Online Courses
We have the following Online Courses (e-learning courses) related to Functional Safety and SIL. Every course, consists of several modules that have text, animations & simulations, graphics, assessments, examples, real life case studies that help you become a professional. You can complete them from the comfort of your home or office or anywhere else. You can either take them online over the internet via any device such as your laptop/PC/tablet/ipad/smartphone or PC. You can even download it to your Windows 10 PC or laptop (when you take the appropriate version). On passing the associated exam, you can get qualified as a professional, earn an electronic certificate with a unique ID number and an electronic badge that can be added to your Linked In Profile or other places online such as email signatures. This displays your qualifications and competencies to your colleagues, peers, bosses and potential employers and clients. Note that however, we do not have any automotive functional safety courses related to ISO 26262.
Safety Instrumented Systems
This course is highly detailed, starts from the basic concepts and covers everything related to SIS including :
a) Basic Concepts
b) Hazard and Risk Analysis
c) Failures and Reliability
d) Safety Integrity Level (SIL)
e) SIS Standards (including IEC 61508 and IEC 61511 / ISA S84)
f) SIS in practice
g) SIS Proof Testing and Maintenance.
Get the Safety Instrumented Systems course now
Functional Safety, SIL & SIS Cybersecurity (Level 1)
This is a first level course on Functional Safety, SIL and SIS Cybersecurity. It can be taken by any engineering or technical professional who wishes to know more about the subject and earn a certificate and electronic badge.
1. Introduction to Functional Safety & Safety Functions
2. Basic Concepts of Hazards, Risks
3. Safety Instrumented Systems
4. Failures & Reliability
5. Safety Integrity Level
6. Functional Safety Standards
7. Functional Safety Management
8. SIS Cybersecurity
You can view more details about the Functional Safety, SIL and SIS Cyber security course here
Functional Safety Professional Practice Test (Free)
If you are planning to enroll into any course related to FS or SIL, not just from Abhisam, but from any provider, then most probably you will have to take an exam after the course.
Taking the Abhisam Functional Safety Mock Test (free) will help you test your own preparation before you take the actual exam. Take the Functional Safety Mock Test now.
Offline Functional Safety Training Courses and Workshops
In addition to the above online courses, we along with our associates, also conduct Functional Safety Training Workshops from time to time in multiple cities around the world. These cover all topics related to Functional Safety including a typical functional safety standard such as IEC 61511. They are offered as public courses but can also be offered as on site training at your location. Our trainers will travel to your location and deliver these programs. They can be customized as per your needs.
Free White Papers
The following free white papers on Functional Safety, SIL and Safety Instrumented Systems are available on the Abhisam website and can be accessed from the links below.
1.An Introduction to Functional Safety and SIL
3. Integrated SIS DCS or separate?
4. High Integrity Pressure Protection Systems (HIPPS)
Functional Safety Posts from the Abhisam Blog
- Become a Certified Functional Safety Professional (Level 1) - Functional Safety Certification Functional Safety Certification is essential for all engineering professionals, who wish to work with Safety Instrumented Systems in industry. Most employers and clients demand that people that they employ have a good understanding of Functional Safety concepts, Standards that are in use and engineering practices. This competency requirement is now mandatory. Take ... Read more
- Certified Functional Safety Professional-Training Workshop in Mumbai-Nov 2017 - Update: July 2020:Functional Safety Training We have suspended all in person workshops, due to the pandemic. But all of these have now been replaced by easy, self paced e-learning Functional Safety courses, that you can take online. They are NOT videos of a professor speaking or a simple power point presentation. They are full fledged ... Read more
- Functional Safety Certification Course IEC 61508 Pune India - Update: July 2020:Functional Safety Training We have suspended all in person workshops, due to the pandemic. But all of these have now been replaced by easy, self paced e-learning Functional Safety courses, that you can take online. They are NOT videos of a professor speaking or a simple power point presentation. They are full fledged ... Read more
- Introduction to SIL & Functional Safety in India-Mumbai and Chennai - Update: These workshops are no longer being held. Now learn Functional Safety, SIL & SIS Cybersecurity when you take the Abhisam online, self paced, Level 1, e-learning course anytime at your convenience and from anywhere via any device. No restrictions at all. Learn everything about Safety Instrumented Systems, Safety Integrity level and the latest updates ... Read more
- Functional Safety Training in Mumbai in April 2016 - Update: These workshops are no longer being held. Now get trained in Functional Safety, SIL & SIS Cybersecurity when you take our online, self paced, e-learning course anytime at your convenience. Course is from Abhisam. Learn every thing that you need to know about Safety Instrumented Systems, Safety Integrity level and the latest updates regarding ... Read more