Dear Mr. Kwon,
there are country wise regulations, how to calculate. f.e. for dust explosion venting in USA you have to follow the NFPA 68, for europe you follow the EN 14491. the best way is to send all available data with your request and we or an international expert will calculate the necessary venting area.
please let me know your fully details by email to sales@rembe.de

My email address is kokwon@jj.ac.kr.
If you are available, would you send me the file that explained Pressure and explosion venting calculation?

If someone needs assistance in pressure and venting calculation, please let me know. our company has huge experience in the process and explosion protection field.