English

The programme ‘Energy Audit’ has been worked out at the Energy Efficiency Centre of the Institute of Physical Energetics, LAS, and may be used for evaluation of heat losses from buildings and the economic efficiency of measures to be taken for their therm

Existing technical recommendations and standards regarding natural ventilation in Portugalestablish one air change rate, ACH, in main rooms (bedrooms and living rooms) and fourACH in service rooms (kitchens and bathrooms).

Currently, a design of the maximum velocity stress in the occupied zone is based on applicationof the jet theory equations or on the data from the manufacturers catalogue. However, thesemethods are based on the idealized test conditions in empty rooms and do not necessarily predictthe conditions existing in realistic rooms with heat sources and sinks. Furthermore, little data isavailable of the distributions inside the occupied zone. A new statistical method for occupiedzone maximum velocity prediction is introduced and verified using experimental data.

The visual evaluation method has been created for a primary method to verify cleanliness ofHVAC system. The results of two simple measuring methods for thickness of dust and debriswere compared to accumulation values measured by vacuum sampling method. The thicknessof dust layer and the dust accumulation results correlated when the dust was homogeneousbut the correlation was poor if the quality of the dust varied. Both the field and laboratorystudies showed that a commercial contact method gave lower microbial counts than the swabmethod with cultivation.

In the present paper, the influence of the initial inclination angle of the jet on the efficiency ofa vertical downward air curtain is analysed. The air curtain device was mounted over anoverture, in the wall between two equal contiguous rooms, with the typical dimensions of adoor.

A combined windcatcher and light pipe (SunCatcher) was installed in the building of theSchool of Construction Management and Engineering in the MSc Seminar Room (2N09).Monitoring of indoor environment in real weather conditions was conducted to evaluate theperformance of windcatchers in the room and to conduct occupant survey. External weatherconditions and internal indoor environment and air quality indicators were recorded. Thetracer gas decay method using SF6 was used to establish the air change rate for variousconditions.

Almost all existing analysis methods for building ventilation airflows, such as the simpleanalytical methods, multi-zone methods and computational fluid dynamics (CFD), give onlyone unique solution for one set of identical input parameters when started with zeroinitialization or zero initial conditions. This can be shown to be incorrect in some situations.Multiple stable solutions are found in some very simple buildings, which indicate that thebuilding airflows are of a nonlinear dynamical system.

Continuous measurements have been operated on 28 identical low energy houses near Leipzig (Germany) during two years.The houses face due south, have two levels and one occupied attic, with a total aera of 147 m2. Heating period is from September to May. All houses except 2 were equipped with different mechanical ventilation systems, providing about 180 m3/hr of fresh air : central balanced flue systems with heat recovery, air heating system with heat recovery, central exhaust ventilation with heat recovery by heat pump, room mechanical ventilation systems.

The system of education in Poland is affected by rapid and deep political, organizational,demographic and financial changes. Although requirements for indoor air quality aredescribed in detail in Polish building codes and standards, the real state of indoor environmentin classrooms is not well documented. However, published studies show that in schools withconventional stack ventilation indoor air quality is rather poor. Unintentionally, very oftenproblems are related to modernized buildings where energy conservation measures have beenapplied.

There is increasing evidence of a causal link between airborne particles and ill health and thisstudy examined the exposure to both airborne particles and the gas phase contaminants ofenvironmental tobacco smoke (ETS) in a bar. The work reported here utilized concurrent andcontinuous monitoring using real-time optical scattering personal samplers to recordparticulate (PM10) concentrations at two internal locations. Very high episodes were observedin seating areas compared with the bar area.