Thermal manikin test and subjective experiments with a desktop based task conditioningsystem were carried out in a climate chamber of Kanto-Gakuin University, Japan. Theexperiments were conducted under three different combinations of ambient air temperatureand relative humidity. It was found that skin temperatures at the upper half of the manikinsbody exposed to the supply air were decreased. Setting of task condition was fixed at first, andthen the subjects were allowed to control the environment freely after a certain period in thesubjective experiments.
Subjective tests with a desktop-based task conditioning system were conducted. Previous tothe subjective tests, detailed measurements of air velocities influenced by the system wereperformed. For subjective experiments, three ambient air temperature and relative humiditycombinations, (1) 27C/40%RH, (2) 30C/40%RH and (3) 30C/70%RH, were applied. Eachof 16 college age subjects was exposed to the three different experimental room airconditions.
By simulating ‘the ramp change of thermal environment’ in the laboratory, we carried out the thermal comfort experiment and observed the changes of subjects' thermal reaction to the ramp change. We compared the effect of air velocity on the change of subj
This report is a part of a study to search whether comfort conditions can be attained by localairflow. In the present experiment, local airflow was directed to two locations of subjectsbody and its effect was examined on which location percepts the airflow more strongly,responds physiologically more sensitively and feels more comfortable. The laboratory airtemperature was set in a range of 26-28C. This experiment was held in summer seasons atToyohashi, Japan.
A novel PMV index based productivity model is derived and it is used to estimate the effectsof different thermal conditions on productivity. Past research findings are used as inputs in thecreation of this productivity loss model. The PMV equation is useful to predict productivityloss that is due to the rate of change in thermal conditions. Using the model prediction, thetheoretical maximum level of productivity occurs when the PMV value is -0.21. Admitting a30% productivity loss in typing-task, the model predicts PMV value ought to be at least+0.63.
In practice, the commonly used Dutch design criterion for long-term thermal comfort inbuildings- the weighted temperature exceeding hours method- often leads to confusion.The criterion is hard to understand for non-experts, and many doubt the validity of thepresent criterion: how sure are we that meeting the requirements really means that futureoccupants will be comfortable?
The primary purpose of heating, ventilating and air-conditioning (HVAC) system is to makeoccupants comfortable. Without real-time practical measurement and method to determinehuman thermal comfort, it may not be feasible that the HVAC system can provide humancomfortable all the time. This paper presents a practical measurement and model to determinehuman thermal comfort index for feedback control. The proposed model is developed basedon the original thermal comfort index called predicted mean vote (PMV) index by applyingfeed-forward neural network model.
Many studies have shown that ventilation systems often host bacteria and fungi that may bedangerous for the health of people exposed to them. This problem may be particularly acute inhospitals, where exposed people are more sensitive. The paper presents the methodologydeveloped to study the effectiveness of some plants extract, the essential oils to hindermicrobial growth, in order to propose an indoor air purification method based on thegermicidal and odorant properties of the essential oils. First results are encouraging.
The use of high-speed rotary and spray-producing instruments can pose a serious risk indental clinics, by continuously creating a potential harmful contamination of the room. Indoorclimate parameters (temperature, relative humidity) and microbiological airbornecontamination (total bacterial count at 37C, fungal particles) were evaluated in 12 privatedental clinics, partially equipped with air conditioning systems. Carbon dioxide airconcentrations were also measured to evaluate the efficacy of air exchange. Air microbialcounts were highest in the consulting rooms and waiting rooms.
The aim of the investigation was to evaluate different methods to sample microbial cell wallagents (MCWA) indoors and to relate the results to clinical markers of inflammation amongpersons (n = 27), living in houses with suspected mould problems. Airborne particles weresampled for 8 h or by agitating floor dust. Sedimented particles were collected from floor dust.Analysis was done for endotoxin and (1?3)--D-glucan. Endotoxin was found only in a few ofthe agitated floor dust samples.