The number of hours during which ΔT is greater than or equal to one degree (°K) during the period May to September inclusive shall not be more than 3% of occupied hours. ΔT is defined as operative temperature less the maximum acceptable temperature. ΔT is rounded to the nearest whole degree.
Please note:
If data is not available for the whole period (or if occupancy is only for a part of the period) then 3% of available hours should be used. It may be seen that educational NCM occupancy profiles are inappropriate due to prolonged unoccupied periods in these profiles. The user should assess the appropriate profiles for their models.
