rooms, including practical spaces, and eg manually opened windows or room computer suites ventilation with on/off and variable speed control Spaces with less than normal level of activity Category II or III or clothing, including sick, isolation rooms, changing rooms and gymnasia and dance and movement studios Special schools and resourced provision, Category I or II where needs of pupils tend to be complex and varied, including pupils with physical difficulties or profound and multiple learning difficulties. pupils or adults may be wet and partially Category II clothed for a significant length of time, such as swimming pools; young children under 5 years old or those Category I with SEN (Special education needs) or physical disabilities may be wet or partially clothed for a significant length of time. More rapid air movement leads to greater chilling by evaporation and to compensate, a higher design temperature is required. Category IV should only be used in classrooms and other teaching spaces where there is local control over the room ventilation with variable speed control with override control by the teacher. The air quality criteria regarding CO2 levels must still be met. Table 74 Draught criteria for mechanical ventilation systems Recommended to provide thermal comfort Draught criteria to provide thermal comfort Winter Summer and mid-season ∆T ∆T (Troom, Category of (Min Maximum Maximum operative - maintained air air plume local operative velocity velocity air temp) temp - plume When Troom (m/s) (m/s) local air or ≤25oC temp) Tcomf 1.5 0.15 1.5 0.15 I
rooms, including practical spaces, and computer suites eg manually opened windows or room ventilation with on/off and variable speed control Spaces with less than normal level of activity or clothing, including sick, isolation rooms, changing rooms and gymnasia and dance and movement studios Category II or III Special schools and resourced provision, where needs of pupils tend to be complex and varied, including pupils with physical difficulties or profound and multiple learning difficulties. Category I or II pupils or adults may be wet and partially clothed for a significant length of time, such as swimming pools; Category II young children under 5 years old or those with SEN (Special education needs) or physical disabilities may be wet or partially clothed for a significant length of time. More rapid air movement leads to greater chilling by evaporation and to compensate, a higher design temperature is required. Category I Category IV should only be used in classrooms and other teaching spaces where there is local control over the room ventilation with variable speed control with override control by the teacher. The air quality criteria regarding CO2 levels must still be met. Table 74 Draught criteria for mechanical ventilation systems Recommended to provide thermal comfort Category of Draught criteria to provide thermal comfort Winter Summer and mid-season ∆T (Min maintained operative temp - plume local air temp) Maximum air velocity (m/s) ∆T (Troom, operative - plume local air temp) When Troom ≤25oC or Tcomf Maximum air velocity (m/s) I 1.5 0.15 1.5 0.15
BB101_Guidelines_on_ventilation_thermal_comfort_and_indoor_air_quality_in_schools.docx