ASHRAE 62.1 requires outdoor air to be provided to corridors - stairs seems to be a grey area ?. If you are using Option 2. CEN Standards EN 15251–2007 and EN 13779–2007 do you require outdoor air to be provided to corridors and stairs ? Seems to be overkill for transient spaces ? Has anyone ever got any clear direction on this ?

Many Thanks,

Ciaran