105. Hygienic evaluation of heating, illumination and ventilation in housing, public including hospital buildings.

12) hygienic evaluation of the heating and ventilation in housing, public including hospital buildings. Lightning.

HEATING

-hygienic requirements: to maintain constant temperature corresponding to the room space; horizontal magnitude of temp. difference has to be 1-2°C, vertical 1-3,5°C; temp. during 24h should not vary more than 3°C in central heating and 5°C in local heating; heating device surface not more than 80°C; producing air velocity no more than 0,6m/s; no noise more than 40db; no emission of harmful substances or pollutants

-description

-instrumental examination of the microclimate (temp., magnitude of differences…)

-temp. of the walls are measure with electric thermometer (at height of 1,5m from the floor, 0,2m from the floor and 0,5m from the window and 0,2m from opposite wall) -> must not be 3°C higher than air room temperature#

VENTILATION

-hygienic requirements: air velocity lower than 0,6m/s; no creation of harmful substances in the air; no “dead spots” in ventilation; no noise or vibration production; easy to contain

-control the quality of the incoming air (best=fresh outdoor air) regarding to its temperature, humidity and purity

-> natural and artificial ventilation

Natural ventilation: organized natural ventilation -> aeration

-key indicators for natural ventilation is CO₂ (amount of air should be sufficient that CO2 concentrations doesn’t exceed the hygienic norms 0,07-0,1 vol.%)

• Volume of adequate air ventilation; cubic space (required amount of ventilation depends on cubic volume of the room for one person presented)->air that one person needs in one hour => V=A/B-C (V=volume of ventilation; A=22,6L/h CO2; B=0,1vol% (normal CO2); C=0,35% (CO2 content in clear air) -> ventilation per person: 35m³/h air
• Actual volume of air ventilation: V=Q*S*T
• Ventilation rate (K): how many times per 1h the room air must be exchanged

Mechanical ventilation: exhaust ventilation (vacuum, induces fresh air to enter the room via windows, door, inlets); plenum ventilation (fresh air is blown into a room, positive pressure and displace the vitiated air); balanced ventilation (combination of exhaust and plenum ventilation); air conditioning (air is filtered, saturated with water vapor and heated to certain temperature, differences of temperature should not be more than 5°C)

LIGHTING (wavelength 380-780nm)

-is essential for efficient vision (loss of efficiency, general fatigue…)

-evaluation

1. Sufficiency: sufficient that the eye can discern the details of the objects
2. Distribution: should be permanent and with same intensity, without production of shadows
3. Absence of glare: excessive contrast, direct or from another light source or reflection
4. Absence of sharp shadows: sharp shadows should be avoided; slight shadows are inevitable