Question: Crude oil storage and handling facilities operating at a total absolute pressure below 0.45 MPa. My understanding of the above paragraph is that, it includes only dead oils with no gas in equilibrium. If any gas is in equilibrium with a crude (operating less than 0.45 MPa) which contains H2S more than 0.3kPa (in the gas phase), the whole system is considered as sour. I need your advice for my understanding, if correct or not?

Answer:

Crude oil storage and handling facilities means that it is dead oil and H2S/CO2 have been removed. The very low residual amount is considered negligible. This is the reason why these facilities are permitted exclusions from the standard. However, it is up to the user to check that these statements are true for the considered facilities.

This question is in relation to NACE MR0175/ISO 15156

Reference: ISO 15156 Maintenance Panel Inquiry #2009-14