The world of functional safety has its own tribal language and acronyms, e.g. safety instrumented systems (SISs), safety instrumented functions (SIFs), logic solvers, final elements (FEs), safety integrity level (SIL), probability of failure on demand (PFD), etc. In a...
IEC 61511
Approaches to Partial Stroke Testing Safety Valves
The safety valve within a safety instrumented function (SIF) must be tested regularly to help assure proper operation in the event of a safety demand. Operators usually perform an offline full stroke test during a scheduled shutdown because of the impact of this test...
Reducing Level Detector Proof Testing Complexity
Each safety instrumented function (SIF) including its sensor, logic solver and final control element must be periodically tested to make sure it will perform as designed in the event of a safety demand. These "proof tests" help to uncover and failure conditions which...
Storage Tank Overfill Protection
Preventing overfill conditions in tanks and vessels is a job for safety instrumented systems across many industries. In a Flow Control article, A Systemic Approach to Storage Tank Overfill Protection, Emerson's Lydia Miller and AnnCharlott Enberg describe the key...
Remote Proof Testing Safety Level Switches
One of the necessities in managing safety instrumented systems throughout the IEC 61511 safety lifecycle is to perform periodic proof tests on the components in a safety instrumented function to verify proper function. A short 2:44 YouTube video, How to Remotely...
Simplifying Safety Valve Proof Testing
A safety instrumented function (SIF) within a safety instrumented system (SIS) consists of a sensor, logic solver, and final element. As part of the IEC 61511 global safety standard, these elements within the SIF must be tested during the operational phase of the...
Partial Stroke Test for Final Elements—Diagnostic Coverage Factors
Partial stroke test is one of the viable means to check mechanical integrity of Final Element of Safety Instrumented Function (SIF) loop. Generally, end users struggle on question of credit of PST for improvement in SIL (Safety Integrity Level). IEC 61508 and IEC...
Flame and Gas Detection in Layers of Protection
For manufacturing processes with hazardous substances that are combustible or can cause harm to people and property, flame and gas detection systems are often used as part of the risk mitigation strategy. This 11-minute video, Rosemount Flame and Gas Layers of...
Managing Storage Tank Pressure and Overfill Prevention
Across the energy supply chain bulk petroleum storage terminals play an important role in managing supply and demand. A critical safety function is to prevent an overfill condition in each of the storage tanks. Another critical function is to manage the pressure...
Filling Gaps in Global Safety Standards
A safety instrumented function (SIF)'s purpose is to reduce the risk of a specific hazard. For example, an upset condition in an oil and gas production separator may cause a series of SIFs within a safety instrumented system (SIS) to shut in the wells feeding the...
Level Sensor Safety Proof Testing
Backing up your computer or server is a waste of time if restoring the backup fails when you need it. Good practice is to test these backups on separate test systems periodically to make sure they restore properly. Similarly, safety instrumented systems (SISs) need to...
Remote Partial Proof Testing Level Sensors
For safety instrumented functions (SIFs), proof testing is the process of identifying undetected dangerous failures in the sensor, final control element and logic solver which comprise the SIF. Dangerous failures are those that could put the safety instrumented system...
Stay up to Date with the Latest News and Updates
Subscribe for Updates
Follow Us
We invite you to follow us on Facebook, LinkedIn, Twitter and YouTube to keep up to date on all the latest news, events and innovations to help you take on and solve your toughest challenges.
Want to re-purpose, reuse or translate content?
Please do, Just link back to the post and send us a quick note so we can share your work. Thanks!
Our Global Community
The opinions expressed here are the personal opinions of the authors. Content published here is not read or approved by Emerson before it is posted and does not necessarily represent the views and opinions of Emerson.