8 replies to this topic

[mido]

I work in a gas plant consisting of four trains.  We propose a shutdown for two trains for inspection purposes.  We discussed positive inspection and clean-out isolation procedures for the vessels with our managers and two plans were studied:

 

Plan A is to isolate every vessel individually (every vessel will have a minimum of three points to achieve positive isolation) a big number of points appears in this plan that required a lot of spades (blind flanges), gaskets, and manpower.

 

Plan B is to positively isolate the boundary limits of each train and isolate the vessels by valves only.  This plan will reduce time, manpower, and materials but our managers refuse to use it because our standards require positive isolation during vessel entry.

 

My question is: Although the standards require positive isolation for every vessel, can we use plan  B which makes positive isolation for boundary limits only - and what are the standards used in isolation required for maintenance???

 

Thank You  

Edited by Art Montemayor, 10 December 2015 - 01:05 PM.
composition, grammar

[siraj paracha]

Well you have to stick with plan A as confined space entry requirements says that vessel or any confined space should be blinded from the nearest points.
Though it will cause you more money in terms of manpower and time but personnel safety is the utmost priority.
Hope this answers your question.
Best of luck.

[breizh]

mido ,

 

Plan A only , with associated permits, atmosphere control , watchers ,.....No compromise .

Good luck.

Breizh

[Bobby Strain]

Would you enter all the equipment isolated with plan B?

 

Bobby

[P.K.Rao]

I agree with plan A. No compromise with human life.

[fallah]

mido,

 

Normally plan A is to be considered...but to evaluate if plan B can be employed, you should provide the detail of the relevant procedure/manual and the schematic diagram of each train including the valves and their sequential actions along with the purging detail... 

Edited by fallah, 10 December 2015 - 10:47 AM.

[manojkaila]

I suggest Plan A and even daily checklist before man entry of all blinds or some visual indication on blind tags. In shut down there are many party & changing work situation. 

[Napo]

Mido,

You can review the book: The safe Isolation of Plant and Equipment by HSE (Health and Safety Executive), UK, 2006.

I hope help you.

Napo.

[mido]

Thanks every one for answers, and from answers i can see that all people prefer to isolate every vessel.

Mr.Fallah, for Plan B the blinds will be at every point in plant which connected to live system ,every vessel have two isolation valves and bleed  and the purge proposed to be two times with 5 barg and 2 hrs continuous purging with N2 for 2 hrs for all the shutdown plant.

Mr.Bobby, not every vessels in the shutdown plant will be entered.

Mr.Napo, Thanks for reference i will download it now.