Incident Report

Subject:                   Info4fire - Pressure vent dynamics and risk peak pressure

Date of Email report:   Tue 25/01/2011

Report Detail:

For many years the use of gaseous fire suppression systems to protect high value or business critical risks have used calculations to determine the required venting areas, to prevent protected risks from being exposed to pressures in excess of their design strength. The calculations used for determining the required free vent area (FVA) have either had a default figure for the performance characteristics or co-efficient of the pressure vent to be used, or this has been ignored or misunderstood by manufacturers.

This article looks at a series of live gas discharge tests carried out using IG55 (inert gas) and FM200 (clean agent) and compares the calculation system used (VdS Software) of FVA. It looks at and introduces the use of a dynamic co-efficient or resistance to opening pressure factors (RTOP) for the actual performance criteria of three types of pressure vents and their direct effects on the risk peak pressure achieved. Due to the critical nature of venting excess pressure from risks protected by inert gases or clean agent systems, we explore the key elements required to accurately calculate the pressure venting needed, which includes the required free vent area and the dynamic co-efficient or RTOP factor to provide a true and safe application of pressure venting systems.

Additional Documentation:

Article and video here: http://www.info4fire.com/main-content/full/pressure-vent-dynamics-and-risk-peak-pressure-video