An improperly sized pressure relief system can cause damage to your facility if you are lucky. Often, serious injury or death can occur as the result of an overpressure in an improperly sized system.

OSHA takes this matter very seriously. It is required that any pressure vessel or relief valve system have up to date calculations on the proper sizing of relief devices within a system. This is true even if the system is not under a Process Safety Management (PSM) Condition. (29CFR 1910.119)

If OSHA discovers that a facility has been neglecting to keep current records on a system after the system conditions are known to have changed, the violation could be considered “willful”. Under a willful condition, OSHA has the authority to fine the facility up to $70,000 for each of the Inlet Pressure Calculations, Outlet Pressure Calculations, Sizing Calculations, and for operating under an undocumented system FOR EACH VALVE OR VESSEL. This could add up to $280,000 for every undocumented relief device or pressure vessel in your facility. A well-known case of this happening was to BP Products North America. (OSHA.gov) Court records indicate that this added up to a $84 Million fine.

How do you know if you need to revisit the calculations for the pressure relief system?

• Has your system had a change in capacity or throughput?
• Has the process changed?
• Has the size of a pressure vessel changed?
• Have the operating conditions changed?
• Have any relief system discharge headers changed?

If any of these line items has changed in your facility, then the pressure calculations need to be revisited and confirmed. An unsafe condition may exist in your facility.

Our Mechanical Engineering staff at VITOK Engineers has had many years of experience in confirming these calculations. We have performed these calculations for diverse industries.

Please feel free to reach out to our experts to learn if you have conditions that would require updated calculations. We are glad to assist you in any way that we can.