Authors assessed building-related risk factors for lower respiratory symptoms in office workers. The National Institute for Occupational Safety and Health in 1993 collected data during indoor environmental health investigations of workplaces. Multivariate logistic regression analyses were used to assess relationships between lower respiratory symptoms in office workers and risk factors plausibly related to microbiologic contamination.
Computed tomography consists in measuring chemical concentrations profiles in a room from the attenuation of a large number of laser rays and converting measurements in a two dimensional concentration profile by a reconstruction algorithm. This study shows the effectiveness of one of these algorithms (Low Third Derivative).
In order to identify the complex flow located at the breathing zone of a seated person exposed to the airflow coming form a PVS (personalized ventilation system) two techniques are used and compared : the PIV ( a two-dimensional particle image velocimeter) and the LDA (laser doppler anemometer) technique with a single point measurement, given by a cross section of laser beams.
The PIV technique appears a very interesting tool in studies aiming at identifying airflow in rooms or around objects.
A new type of thermal manikin DRESSMANN (Dummy Representing Suit for Simulation of huMAN heatloss). is presented : it consists of an overall, that can be worn by a person or a manikin, on which up to 32 heated sensors (artificial skins) can be fixed everywhere by velcrose fastening.
DRESSMANN presents the advantages of heated dummies and of small sensors . It can be used in buildings, vehicles, planes or trains.
For that study , an heated manikin, in a seated position, is exposed to a local thermo ventilator that promotes a non-uniform horizontal flow ( front , behind and right side) ; an interior climate analyser measures the environmental variables around the manikin. Those data are used as inputs of the numerical program.
A numerical model simulates the human and clothing thermal systems and evaluates the thermal comfort level. Verification was made that when the ventilator is places in front of the manikin, acceptable thermal comfort conditions are fullfilled.
This paper reports a large-scale investigation result on seat occupancy rate in a typical Japan office with 240 workers. The experiment lasted 3 months. The sensing device continuously recorded the seating status for about one week for each working person. From these results , a practical use situation of the personal air-conditioning system in the office could be predicted.
The aim of that study is to make a database of the local convective heat transfer coefficients for each part of a human body in sedentary and standing environments through the use of an experimental thermal manikin and an analysis of the radiative heat transfer rate. The results are applicable to both indoor and outdoor environments.
The paper also discusses the influences of wind velocity, sensible heat loss, posture and furniture arrangements on local convective heat transfer coefficients values.
This paper investigates the possibilities to create velocity variations of that type : (change from "low" to "high" velocity and then back "low" velocity again) in a whole room using standard velocity components. The results show large differences at individual points, but the mean value of all 8 positions in the room shows an expected behaviour.
This paper proposes a simple mathematical model for calculation of the convective air flow rate induced by humans. That model has been then compared to a more complex one and to experimental data with satisfactory results.
By means of CFD, the results of that study express a significant influence of Computer Simulated Person geometry on local flow pattern and on personal exposure to contaminants released from the floor surface.