Exhaust Smoke Validity of Vertical Shaft in Restrooms using the Stack Effect

This study is performed to validate a quantitative relationship between the exhaust rate through vertical shaft, which are used for restroom ventilation, and smoke generation based on NFSC 501. The exhaust rate is calculated using heat balance equations and is based on the input and exhaust air temperatures. The neutral plan in the vertical shaft was formed at approximately 46% of the total height. Because the smoke that is exhausted through the vertical shaft is more than 20% of the minimum smoke generation suggested by NFSC 501, the smoke exhaust through the vertical shaft is considered to be possible.