Calculating the contamination concentrations in a space or the required ventilation for a spacehas been a difficult and confusing part in the application of the IAQ Procedure ofANSI/ASHRAE Standard 62, Ventilation for Acceptable Indoor Air Quality. Appendix D ofASHRAE Standard 62 currently presents one method for performing these calculations, but itis limited to the steady-state analysis of a single zone.

The traditional ways of maintaining cleanliness, temperature and moisture level in anoperation theatre (OT) usually use larger HVAC system and keep both the heating andcooling functions operating at the same time. The temperature and moisture level are thusunder control at the cost of tremendous amount of wasted energy. Incorporating the HVACsystem with the newly developed secondary return air system, the system capacity can bereduced while the energy efficiency can be increased. In this paper, concepts of the secondaryreturn air system are described.

An assessment concept is being developed for iterative design of office buildings withintegrated energy and indoor comfort solutions. An indexing system has been devised thatincorporates environmental effects of energy use with thermal and atmospheric indoor climatein a score on a common scale from 0 to 100%, called the Eco-factor. Only the operativephase of the building life cycle is considered. Only indoor climate aspects that are closelyinter-related with energy use are considered: Thermal comfort and Indoor Air Quality.

A Personalised Ventilation system provides occupants with means of adjusting their individualthermal environment and of achieving good indoor air quality. The individual control ofenvironmental variables makes it possible to compensate for the differences between people withregard to their requirements. In most tropical designs, the air-conditioning and mechanicalventilation system maintains the indoor spaces at cold temperatures in the vicinity of 21 C.

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

The quality of air in the indoor environment is dependent on the nature and source of indoorpollutants and the performance of the ventilation system. Increased dilution in a tropical contextimplies a high energy penalty. This paper presents a novel method of addressing IAQ and energyissues. An innovative energy efficient method and means of air-conditioning for an independentcontrol of temperature and humidity of two different air streams has been developed.

A thermal comfort designer is especially concerned with creating an environment to improvethe physical, mental and psychical health of human beings. The general thermal state of thebody both in comfort and in heat or cold stress is dependent on an analysis of the heat balancefor the human body. Traditional methods of thermal analysis are based on the first law ofthermodynamics. By contrast, the second law of thermodynamics introduces the usefulconcept of exergy in the analysis.

Problems of heat and mass transfer optimization in the plate cross-flow heat exchangers, usedin air conditioning systems for energy recovery from exhaust air, are discussed. The mainpeculiarity of the investigated unit is the possibility of realization of heat transfer withinexhaust air canals in the dry heat exchange conditions or in the conditions of coupled heatand mass transfer with occurrence of vapour condensation on the whole or on a part of theheat exchange surface of the matrix in the form of dew or frost.

In this paper, the very recent laboratory research results on personalized air supply (PAS)from three universities are critically reviewed. Based upon these experimental results, thepotential improvements on inhaled air quality versus indoor air quality are analysed in termsof reduced air pollutant levels in the inhaled air. Depending on the configuration of the PAStested, up to 80% reduction of pollutant levels in the inhaled air can be achieved at the sametotal ventilation rate of the present mixed ventilation methods.

Air-conditioning and ventilation systems, which help to maintain the indoor environment ofbuildings, account for more than half of the energy consumed in them. While it is necessary toimprove the energy efficiency of buildings due to economic and environmental reasons, it isimportant to do so without compromising their indoor environment. Various optimizingstrategies for air-conditioning and ventilation systems that help to improve energy efficiencywhile enhancing the quality of the indoor environment of buildings are described in this paper.