The ‘time out of range’ (TOR) requirement is satisfied when a significantly better performance is justified to have been achieved in comparison to the appropriate industry standard. Where there is no appropriate industry standard available or TOR recommendation, the building services engineer needs to confirm the TOR is acceptable for the specific building.
Where there is a reference to 60 hours TOR in relation to Building Bulletin 101 recommendations, this is purely for illustration and not a compliance requirement.
