Dear Mr. Roger Chang

I was hoping if you could provide some information on the ASHRAE 62.1 2007 standard related to "Minimum Ventilation rates in breathing zone" for Hotel room applications. It has been mentioned that the outdoor air rate per person(cfm/person) for bedrooms/living rooms in hotels should be 5 compared to the earlier standard which said 11 cfm/person. This would probably mean a cfm of 10 per room which is considered to be low. Earlier the cfm requirements per room used to be 30. Also, the 2007 standard suggests 30 % more fresh air intake which would also result in the increase in contaminants in some countries where the quality of outdoor air is not good. So if we consider the CO2 level which should generally be 1000 ppm per zone, how much would increase in percentage of fresh air intake affect the CO2 level and how much should it go down approximately.

Can you please provide information on this matter and how does the 2007 standard work for hotel room applications.

Thanks!!