Energy efficient behaviour was studied by a questionnaire addressing office workersaltogether in 34 office buildings in Finland, Sweden, the Netherlands, France and Italy. AFinnish occupancy study of the possibilities to adjust working environment and thus gainbetter working efficiency offered comparative reference results on similar themes.The possibility to control personal working environment was most important for the officeworkers. The qualitative building automation had a positive influence on the feedbackregarding workspaces.
This paper presents the findings of a short-term monitoring exercise and questionnaire surveyto assess the thermal comfort conditions actually being achieved in 6 Iranian Office buildings.The findings of the questionnaire and monitoring are compared to give confidence that thequestionnaire is accurately reflecting the calculated comfort conditions obtained from thephysically monitoring and site observations.
Subjective experiments were carried out in a climate chamber using 16 Japanese subjects ofboth genders, in order to evaluate human comfort at very low humidity. Two levels ofabsolute humidity were set, 2.0 g/kg(DA) and 10.0 g/kg(DA). Three air temperatureconditions with absolute humidity of 2.0g/kg(DA), 20.0C/13%RH, 25.0C/10%RH and30.0C/8%RH, and 3 conditions with 10.0g/kg(DA), 20.0C/68%RH, 25.0C/50%RH,30.0C/38%RH, were examined. People were exposed in a chamber for 90 minutes withsedentary activity.
Physiological parameters measured by an embedded body sensor system were demonstratedto respond to changes of the air temperature in an office environment. The thermal parameterswere monitored with the use of a wireless sensor system that made possible to turn anyexisting room into a field laboratory. Two human subjects were monitored over dailyactivities and at various steady-state thermal conditions when the air temperature of the roomwas altered from 22-23C to 25-28C. The subjects indicated their thermal feeling onquestionnaires.
Thermal comfort studies and standards show that room temperatures should be higher in thewarmer season than in the colder season. An interview survey with a sample size of 3,094people was performed in Finland. The respondents were asked to state the Celsius values ofroom temperature they prefer in the winter and summer season in living room at home. Theresults show that people have a false idea of comfortable temperatures. 41% of therespondents think that room temperature should be lower in the summer season than in thewinter season.
This paper describes a methodology for improving individual thermal comfort in an officebuilding without increasing energy consumption. Our approach is based on the observationthat an individuals preferred temperature is not a precise value, but a range around apreferred value. We take advantage of this to optimize the temperature settings of eachoccupants personal space to minimize the overall energy use. We have employed a nonlinearprogramming approach to improve individual thermal comfort without increasing energyconsumption, even possibly saving energy.
Entrance of snow into the HVACsystemsis common problem in the arcticandsubarcticclimates and may cause moistening or wetting of filters and outdoor air chambers whichpromotes microbe growth. Blocking the filters also increases pressure drop or even damages thefilters. The design features and velocity of air in the outdoor air intake play key role when theproblems occurs. To eliminate the snow entrance into the HVACsystemsthe face velocity of theoutdoor air shall be below 1 m/s at the intake louvre.
Since the study by P.O Fanger (1988) [1] we know that the Heating Ventilating and AirConditioning (HVAC) system could be responsible for a large amount of indoor air pollutionand Sick Build Syndrome (SBS). The pollution could become from filters, cooling coils anddust accumulated on duct surfaces in systems with poor maintenance.While the importance of maintenance of air handling units and replacement of air filters iswell recognized in Portugal, the cleanliness of ducts is sometimes forgotten.
Man made mineral fibers (MMMFs) that can cause irritation in upper respiratory tract, eyesand skin, can be emitted to indoor air from the HVAC system. A Finnish project was set up tomeasure fiber emissions and to develop design and materials of the HVAC systems toimprove indoor air quality. Within the project laboratory tests and field measurements werecarried out.As a result, new methods of testing the emission rates of the MMMFs from HVACcomponentshave been developed. With these methods HVAC-components can be classifiedwithin the Finnish Indoor Air Classification.
The published REHVA guidebook provides comprehensive uptodateinformation aboutdesign features, criteria for cleanliness, inspection and cleaning instructions of ventilationsystems. The guidebook is aimed at practitioners, designers and those who are setting criteriafor cleanliness of ventilation systems. The design practice includes guides to construct a cleanventilation system and which cleanliness can be maintained during whole lifetime of thebuilding.
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