API RP 500, Appendix B - Minimum Air Induction Ratio to Achive Adequate Ventilation Using Fugitive Emissions

Written by Jerry Ratzlaff on . Posted in Electrical Engineering

Total Hydrocarbon Leak Rate formula

\(\large{ G =  \frac{ E \; V }{ 60 \; mw  }   }\)   

Where:

\(\large{ G }\) = leak rate

\(\large{  E }\) = emission rate

\(\large{ V }\) = volume

\(\large{ mw }\) = average mole rate

\(\large{ 60 }\) = minutes/hour

 

Hydrocarbon Concentration formula

  • As per NFPA 69 - Explosion Prevention System
\(\large{ C =  \frac{ G }{ Q } \; 1 \; -e^{-kn}    }\)   

Where:

\(\large{ C }\) = concentration of hydrocarbon in air, percent (expressed in decimal formula)

\(\large{ G }\) = leak rate

\(\large{ Q }\) = fresh air induction rate, cfm

\(\large{ n }\) = number of air changes