Air exchange standards.
The volume of air supplied to the ventilated room per hour can be approximately calculated, using the concept of the so-called. air changes per hour, which is:
where: n - air exchange rate,
L - volume of air supplied to a given room per hour in m³ / h,
V - room capacity in m³.
The amount of air supplied to a given workplace should correspond to the standards necessary for the proper course of human life processes, i.e.. 30 m³ / h for one man. In accordance with applicable regulations, natural ventilation - gravity should be used in all rooms of the gastronomic establishment, and also in the consumption room, the kitchen, dishwashing rooms and preparation rooms - mechanical supply and exhaust ventilation, not related to the ventilation of the building.
Mechanical ventilation must provide:
• in consumption rooms 10-12 air exchange and the temperature of the supply in winter 18 ° C;
• in the kitchen 15-30 air exchange and air supply temperature in winter + 20 ° C and exhaust air discharge through a hood above the kitchen hearth;
• in the prepress room 4-8 exchanges and in the washing room 5-10 exchanges at the supply temperature + 20° C in winter and the connection of the duct system to the kitchen ventilation;
• expense lifts in toilets 50 m³ / h na 1 toilet seat and 20-50 m³ / h per pen.
In winter, ventilation must not lower the temperature maintained in the rooms by the heating devices and may not cause the air flow velocity to exceed above 0,3 m / s in the zone where people are.