Air velocity in a ventilated room ?

[TonyVink]

I want to place a combination of gas cylinders in a ventilated enclosure. Ventilation is 140 times the room content (8 m3) When work is done on the gas cylinders the doors of the enclosure are fully open. Does anyone know how to calculate the air velocity in the room when the doors are open and closed?

 

[JLSeagull]

Ventilation velocity is often described in terms of air changes. See NFPA 496 for example guidelines. You need to include the rate such as 140 times the room volume per fortnight. The leakage rate or exhaust rate would provide the velocity data with the doors closed. Calculate the area of the openings such as all doors. Some HVAC systems are push-pull with supply and exhaust fans. Consider this too. The HVAC forum could be helpful too.