Guidelines on ventilation and air conditioning

[Download the digitally-signed recommendations in PDF format]

In view of the situation that we are currently facing and the queries raised by different UGR centres regarding the guidelines on ventilation to maintain acceptable indoor air quality, both in teaching facilities and in workplaces, we wish to communicate the following recommendations drawn up by the Health and Risk Prevention Service (SSPRL) and the Technical Unit.

These general recommendations are additional to and compatible with those already indicated in the preventive measures of the University of Granada for the on-site return of staff in the face of Covid-19, which are included in the amendment of Specific Procedure No.22 “Preventive Measures of the UGR Plan for the On-site Return of UGR Staff in the face of Covid-19”, developed by the Health and Risk Prevention Service and unanimously approved by the UGR Health and Safety Committee (CSS) in its session of 18 June 2020.

  • In harsh winter periods the heating will be switched on an hour before the normal time.
  • Even if the weather conditions are adverse, natural ventilation will be maintained via open windows and doors.
  • We must bear in mind that given the situation we find ourselves in, energy efficiency and conditions of comfort will be affected, since health criteria must take precedence in all instances. However, taking into account the diversity of our centres and buildings, as well as their characteristics, an attempt will be made to strike a balance between healthy and comfortable conditions. To offset the lack of thermal comfort, we recommend using more warm clothing.
  • When ventilation by natural or mechanical means is not possible, the use of air purifiers should be considered. As they require a more detailed study to meet the required standards and to be truly effective as purifiers to tackle Covid-19 contamination, they may only be installed under the approval of the SSPRL. This equipment is designed for very specific rooms in terms of size and capacity, and can lead to a false sense of security that can be harmful. In addition, a safety protocol must be established to prevent biological risks owing to maintenance and changing the filters.
  • In general, for queries or clarifications regarding the ventilation system of each centre or room, consult the maintenance staff.
  • Try to ensure that the external air flows that are generated circulate between windows, or between windows and doors, in order to effectively extract the air inside spaces.
  • When rooms are occupied, and provided the outdoor weather conditions allow, windows will be kept open (to try to create a cross-flow of air as mentioned above). If the weather conditions do not allow this, the windows will be kept open for ten minutes every fifty minutes.
  • The ventilators will run continuously and at 100% at all times while the room is occupied, starting two hours before the room is used and operating up to two hours after its use.
  • Units/machines that feature an “all external air” mode (without recovery) will run in this mode. For units/machines that do not have this feature, maintenance staff will check that there is no air flowing from the air being extracted to the air being blown in.
  • All air handling units and equipment that can operate solely using external air will do so in this mode.
  • In the Annexes we detail how each space must be managed based on its characteristics.

Javier Machado Santiago    
Director for Health and Risk Prevention (SSPRL)

Juan Francisco Moriana Ávila
Director of the Technical Unit

Ventilation of spaces (classrooms, administrative areas, laboratories, and workspaces in general) without mechanical ventilation

  • Since the cleaning, disinfection and ventilation of these spaces takes place the day before (at the very end of the day), it is not necessary to ventilate them naturally first thing in the morning, especially on days with low temperatures, since they have already been disinfected and ventilated.
  • Ventilation will be carried out for ten minutes between classes and throughout the workday in the remainder of administrative and/or work areas, during which time all windows and doors will be kept open.
  • If the weather conditions permit, the windows will remain open for the entire class and the entire workday.
  • If the weather conditions are adverse, the windows and doors will be opened to generate a cross-flow of air that allows the air to be renewed, for ten minutes every fifty minutes.
  • At the end of class, the doors and windows will be opened again until the start of the next class.

Ventilation of spaces (classrooms, administrative areas, laboratories, and workspaces in general) equipped with mechanical ventilation

  • Since the cleaning, disinfection and ventilation of these spaces takes place the day before (at the very end of the day), it is not necessary to ventilate them naturally first thing in the morning, especially on days with low temperatures, since they have already been disinfected and ventilated.
  • Two hours before the start of classes and the workday, the ventilation system will be switched on in "all external air" mode.
  • For the duration of classes and the workday the system will be kept on constantly.
  • After classes and at the end of the workday, the system will be kept on for the following two hours.

Additional remarks:

  • If in doubt, consult the maintenance staff about the mechanical ventilation system available at the centre/building in question.
  • If it is possible to naturally ventilate the rooms, this will be used to complement the mechanical ventilation system.

 

Imagen
Docente abre las ventanas de un aula