SIS and HIPS - difference

[Buchi]

Hi gangs,

i have been trying to figure out the major difference between SIS (safety instrumented system) and HIPS (high integrity protection sytem), can somebody help out here?

Buchi

Buchi

 

[Guidoo]

You wrote "HIPS", where I am used to the term HIPPS, being High Integrity Pressure Protection System (see for example NORSOK standard P-001).

A HIPPS is a Safety Instrumented Function (SIF), provided to protect against overpressuring and with a high integrity (so with a low probability of failure on demand/a high Safety Integrity Level (I would say SIL3).

As described in the IEC 61511-1, a Safety Instrumented System is an instrumented system used to implement one or more Safety Instrumented Functions.

So in short, a HIPPS is just another word for a SIF with SIL 3 to prevent exceeding of design pressure. The term HIPPS was probably invented before IEC 61508/61511 and terms like SIS, SIF and SIL were invented.

 

[Guidoo]

In addition to my previous reply, I found following definition on the web:

"High Integrity Protection System (HIPS) are Safety Instrumented Systems (SIS) implemented to address overpressure scenarios in lieu of a Pressure Relief Valve (PRV). HIPS essentially replaces the PRV for those scenarios that the SIS is designed to prevent. HIPS applications are generally pipeline and pressure vessel overpressure protection."

So in order for a SIS (SIF?) to be a HIPS/HIPPS it is to be provided to address overpressure scenarios in lieu of a PRV.

 

[Buchi]

Hi Guidoo,

i really appreciate your sole contributions to this issue. It has gone a long way in educating me on this topic.

Buchi