Ozone's impact on public health : contributions from indoor exposures to ozone and products of ozone-initiated chemistry

In this paper, the author examines the contributions of indoor exposures to ozone and its ozone-initiated oxidation products to ozone's overall impact on public health. He presents relatively simple strategies that could mitigate those effects. For example, by filtering ozone from ventilation air and by limiting the indoor use of products and materials whose emissions react with ozone.

Prevalence and implementation of IAQ programs in U.S. schools

in that study the extent to which US schools are implementing IAQ programs is analyzed. It appears that having a program is not equivalent to implementing effective IAQ policies and procedures. The survey results indicate that schools are paying an increasing amount of attention to IAQ and when actively supported by the school administration the program appears a good means to improve the learning environment for US schoolchildren.

Factors affecting the association between ambient concentrations and personal exposures to particles and gases

In that paper, the data collected in a previous study was used to examine the impact of season, home ventilation, and particle composition on associations between ambient concentrations and corresponding personal exposures to particles and gases. The results suggest that ventilation may be an important modifier of the magnitude of effect in time-series health studies, and that results from time-series health studies are more readily analysable for particles than for gases.

A new formula for determining a minimum recommended value of inlet air velocity from UFAD system to prevent occupants from draught risk

Numerical simulations were executed to estimate air movement in a typical room.The analytical estimation of minimum value of inlet air velocity from UFAD system has been confirmed by those simulation results of temperature and velocity distributions..

Real-time evaluation of ventilation filter-bank systems

Two government facility ventilation systems were evaluated in that study, one with a recirculation system, and the other one that used 100% outside air with no recirculation. For the two systems different filters have been tested : low-efficiency bag filters and medium-efficiency filters for the first one and electrostatic bag filters and V bank filters for the second one. The results of a 3 year evaluation are presented.

Correlation between airflow patterns and performance of a laboratory fume hood

For that paper, the three-dimensional flow patterns and the real-time tracer gas leakage were studied to understand the physical mechanisms of the contaminant dispersion and containment leakage during the ventilation process through a laboratory fume hood. In that aim the laser-assisted flow visualization method and the standard/special gas sampling technique were used.

Designing a dedicated outdoor air system with ceiling radiant cooling panels

In this paper , eight simple steps for designing a DOAS with CRCP system are provided . They consist in the determination of design outdoor air conditions, target space conditions, design cooling load and required ventilation rate for each space, supply air conditions, enthalpy wheel effectiveness and design cooling coil load, sensible cooling load for the CRCP system, design panel cooling capacity. The following of those steps should be very useful for engineers considering a DOAS/CRCP system.

Research report on effects of HVAC on student performance

The objective of that experimental field study was to investigate if a better indoor air quality in classrooms improves the performance of schoolwork for children. The results demonstrate that thanks to an increase of the outdoor air supply rate, or a moderate reduction of elevated classroom temperatures, the performance of a wide range of schooltasks are improved.

Calculation tools for the ventilation rate procedure

HVAC engineers have to incorporate the calculations and directives of the Ashrae standard 62.1-2004 into the normal design process to improve ventilation air delivery. Calculation of the ventilation rate procedure are difficult but several tools exist to make it easier.

Predictive models of control strategies involved in containing airborne infections

The objective of this paper was to develop a flexible mathematical model that could help to determine the best strategies for containing indoor airborne infections at the early stage of outbreak.The impact of engineering control measures combined with public health interventions was examined mathematicallyl.

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