Safety 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.

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 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.

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 computerized Automation systems such as DCS or PLC or SCADA or a SIS, 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.

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 or download it to your Windows PC (when you buy the Standard version). On passing the associated exam, you can get qualified as a professional, earn an electronic certificate with a unique ID number and a badge issued via Credly, 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.

Safety Instrumented Systems

Safety Instrumented Systems Training

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 System course now

Functional Safety,  SIL & SIS Cybersecurity (Level 1)

Functional Safety SIL Training

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

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 here.

Functional Safety Professional Practice Test (Free)

Safety Instrumented Systems Training

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 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 Safety Integrity Level.

 2 Safety Instrumented Systems- Design Tips for engineers

3. Integrated SIS and 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