If you are done with pneumatic or hydraulic testing then there are much less chances of leakage.
So, operators roam around the circuit during gas introduction & operation, so no barrication etc required. But access control must be practiced. no trespassing etc.
Moreover, you should keep following ...

Before introducing H2,
Purge the whole circuit with Nitrogen to displace all the Oxygen.
Pl keep following things in mind during N2 purging:
1. Connect N2 from the very 1st (upstream) available point in the circuit.
2. Pressurize the circuit to the N2 header pressure (around 4 to 8 bar) keeping ...

Very well done Waseem.
Your efforts are appreciated.

Dear Fraz,
Pl go to the topic titled "SIL" on "HSE Engineers" forum of thepetrostreet. It'd hopefully help you thru.

SIL : Safety Integrity Level

Training seems very good & helpful.
I strongly recommend HSE beginners & production / maintenance guys to go for it.

Well Done thepetrostreet team.
It's THE DIGNIFIED WAY to celebrate Independence Day.
God bless you.

O Gr8 ! ! ! !
Keep releasing..........

Great !!
Lookin forward to see another handy tool.
Congrats in advance.

Thanx a lot arcpro.
We'll definitely consider the points hilited by you.
Pl share whatever aspects come to your mind

Thanx Ashfaq.
I'm using this document as guide as well as a legal requirement.
More importantly I'm interested in getting some pratical info from some experienced individual.