Ken Moore
Lifetime Supporting Member
Any of you folks have to work with a process that's covered by OSHA PSM? How do you handle management of change when it comes to plc or dcs logic?
My plant has a general management of change procedure that's used for everything from changing a valve to changing plc logic, and it doesn't work that great for the plc logic.
If I need to change logic, be it one line or 100 lines. I have to document why, when, and the expected results. Then three other people have to sign off on the changes before they are made. Of these three people, one is the safety guy and knows nothing about PLC's, one is the department supervisor, knows nothing about plc's, and one is the engineering supervisor, once knew plc's, but hasn't done any programming in years. He always approves the changes.
So I have a piece of paper that okay's the changes, and it's been approved by three other people. My butt is covered. But, it's just a piece of paper, I could easily blow the place up, and the three guys reviewing my changes wouldn't have a clue.
I'm good, but I'm not perfect, someday I fear that I will overlook something important.
Does anyone have a better method?
Whenever we get audited we always pass, because we have a management of change program in place, and use it. It doesn't matter that it's ineffective. In my opinion software changes should be reviewed by people that understand the changes. Not the same people that review changing out a valve or pump.
Just ranting, but any and all suggestions would be appreciated.
Ken
My plant has a general management of change procedure that's used for everything from changing a valve to changing plc logic, and it doesn't work that great for the plc logic.
If I need to change logic, be it one line or 100 lines. I have to document why, when, and the expected results. Then three other people have to sign off on the changes before they are made. Of these three people, one is the safety guy and knows nothing about PLC's, one is the department supervisor, knows nothing about plc's, and one is the engineering supervisor, once knew plc's, but hasn't done any programming in years. He always approves the changes.
So I have a piece of paper that okay's the changes, and it's been approved by three other people. My butt is covered. But, it's just a piece of paper, I could easily blow the place up, and the three guys reviewing my changes wouldn't have a clue.
I'm good, but I'm not perfect, someday I fear that I will overlook something important.
Does anyone have a better method?
Whenever we get audited we always pass, because we have a management of change program in place, and use it. It doesn't matter that it's ineffective. In my opinion software changes should be reviewed by people that understand the changes. Not the same people that review changing out a valve or pump.
Just ranting, but any and all suggestions would be appreciated.
Ken