exida explains Blog

How the PHA and LOPA are going to affect your SIS

How the PHA and LOPA are going to affect your SIS

Both Process Safety Analysis (PHA) and Layer of Protection Analysis (LOPA) occur in the early stage of the Functional Safety Lifecycle, detailed in both IEC 61511 and IEC 61508. They both serve significant roles in the whole process safety management. Yet, as a facilitator…

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Share the Wealth (of Functional Safety Knowledge)

Share the Wealth (of Functional Safety Knowledge)

Experience is a good teacher.  But how do you get the experience?  

Formal classroom or online training is often available for more general skills, but on-the-job training usually provides a more in-depth path to gain such experience.  After doing a job for a while, working through difficulties with colleagues,…

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IEC 62061 Machine Safety: “It’s simply the right thing to do”

IEC 62061 Machine Safety: “It’s simply the right thing to do”

I can't begin to tell you how many of our customers share with us how lucky they have been to be incident-free at their plant.

Or, because they have not had an incident in over 10 years, it is hard to justify the cost of a Machine Hazard…

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Back to Basics: Failure Rates - λS

Back to Basics: Failure Rates - λS

The Greek symbol  λS represents safe or spurious failure rates in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).

λS is the number of safe…

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IEC61511 and Failure Rates

IEC61511 and Failure Rates

Most end users I teach in our FSE100 class are not really aware of or fully, understand when we talk about failure rates.  For example, what’s a FIT mean?  For those end users more versed in this, they understand what is meant by a FIT.  Essentially a device can have…

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Know Your Human Error (Part II)

Know Your Human Error (Part II)

 

“…there is a belief amongst many engineers and managers that human error is both inevitable and unpredictable. 

However, human error is inevitable only if people are placed in situations that emphasize human weaknesses and that do not support human strengths”

Martin Anderson, IChemE Safety and Loss Prevention…

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Functional Safety Management Systems & Engineering Companies

Functional Safety Management Systems & Engineering Companies

In recent discussions with several engineering and integrators of Safety Instrumented Systems (SIS), it’s become very clear to me that the majority I have spoken to, don’t have any form of Functional Safety Management System (FSMS) in place.  This is interesting because one of the changes in the…

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OLD component data = Bad FMEDAs

OLD component data = Bad FMEDAs

When we first invented the FMEDA technique in the late 1980s the biggest problem was the component failure rate and failure mode data.  Still is.  I picked up a well-known standard for component failure rates and saw a date of 2010.  The technology world has gone through an order of…

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Back to Basics: Failure Rates - λDD

Back to Basics: Failure Rates - λDD

The Greek symbol  λDD is the detectable dangerous failure rate in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).

Lambda DD

λDD is the number of…

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Risk Management in the News

Risk Management in the News

I just read a great article in the May issue of IEEE Spectrum magazine called “Managing Risk and Responsibility During a Crisis.”  The author Robert N. Charette says “If the American people desire the federal government to be their risk manager of first resort, then an open and…

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What is Prior Use Justification?

What is Prior Use Justification?

When it comes to IEC61511 and the selection of equipment for use within Safety Instrumented Systems (SIS) and Safety Instrumented Functions (SIF), there are only two methods that can be used to justify selection: IEC61508 Certified devices for the required SIL or Prior Use Justification.  Just…

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Know Your Human Error (Part I)

Know Your Human Error (Part I)

Increases in levels of automation and system complexity impact human error. Medical errors in hospitals and clinics result in approximately 100,000 people dying each year and cost the healthcare industry between $4B – $20B each year. In the petrochemical industries, operational error can cost upwards of $80M per incident. “Operator error”…

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Back to Basics: Failure Rates - λDU

Back to Basics: Failure Rates - λDU

The Greek symbol  λDU is the undetectable dangerous failure rate in functional safety expressed in the unit of measurement of FITs which can be determined through FMEDAs. (FITs (λ) are failures per billion hours, expressed by 10-9 hours).

λDU is the number of dangerous undetected failures…

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What’s inside a COVID-19 Ventilator?

What’s inside a COVID-19 Ventilator?

At exida, we just finished a Failure Modes and Effects Analysis (FMEA) on a medical ventilator. This was done for a new manufacturer who needed independent design verification.  It was a fascinating job.  We found lots of pneumatic devices very similar if not identical to the kind used in…

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10 Years After, Has Anything Been Learned from Deepwater Horizon?

10 Years After, Has Anything Been Learned from Deepwater Horizon?

It’s hard to believe that it’s been 10 years since the Deepwater Horizon incident on April 20th 2010.  Even today, the Gulf Coast is still feeling the effects.  In its latest estimates, BP is looking at a total loss of $65Bn USD, in settlements, fines and compensation.  This latest estimate was published in…

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