air cleaning

An experiment was carried out to determine the effect of photocatalytic air cleaning on perceivedair quality. Thirty-eight subjects assessed the air quality in a low-polluting, 108 m3 office, with pollution sources either present or absent behind a partition. The pollution sources were carpet, linoleum and chipboard. The office was ventilated with outdoor air at 0.6, 2.5, and 6 h-1. The air temperature was 22C and the relative humidity 40%.

Electrostatic air cleaners (precipitators) were tested in four classrooms during ordinarylessons for four weeks. Airborne dust in the classrooms was collected on filters using two different kinds of samplers: IOM-sampler and a new kind of ionizing sampler. The amount of collected dust was evaluated by visual inspection (filter blackening) and the content of cat allergen was measured using an amplified ELISA assay. It was found that the filter blackening was 64% lower when the air cleaners were active than when they where inactive (p

There are many schoolchildren who have a minor chemical sensitivity and cannot go toschool just because of the activities taken place such as arts & craft, waxing the floor or justopening the textbook. The solution for those children to go school is to protect them fromthose chemicals. However a renovation to make the whole classroom into a chemical freeroom is not a realistic solution for just one child not just because of its cost but also the effectto the other schoolchildren going in and out from chemical free room because of the risk ofrebound.

Various air cleaning technologies and products are commercially available to remove VOCsfrom indoor environment. By conducting full-scale chamber tests, this paper compares theremoval characteristics for VOCs between three commercial portable room air cleaners,representing three major types of technology: sorption filtration, ultraviolet-photo-catalyticoxidation (UV-PCO) and ozone oxidation.

The aim of the study was to evaluate the technical and financial impact of the ENV 12097 requirements and to compare them with the “state of the art” in France. The comparison has been carried out on the basis of a case study consisting in a three-floor o

The aim of this document is to outline and summarize the principles to be followed when the aim isto produce and to install a clean air handling system. A large Finnish research and developmentproject CLEAN VENTILATION has focused on to find the main reasons and phases where theodours and other harmful pollution from the ventilation system originate. In the project bettertechnical solutions have been developed to produce cleaner components with less harmfulemissions.

The excitation of pulsed plasmas for the air treatment (odors, toxic and volatile gases suppression, and sterilization) needs fast high electric pulse generators with powers that can require high repetition frequencies according to the applications .This paper shows that those solid state generators are today available. They use several technologies thanks to a global approach of the high power electronics physics and recent evolutions of active and passive components.

The heterogeneous photocatalysis relies on the activation of a half-conductor. The most often used is TiO2, with radiations of energy at least equal to the ones of the width of the forbidden band.The electronic changes due to that activation lead, in the presence of air, to the creation of oxygenated radicals. Those radicals attack the adsorbed organic compounds and degrade them. Starting from evaluations made with a laboratory photoreactor, this paper shows that photocatalysis is an appropriate method to purify air in domestic buildings (or other confined spaces).

The Volatile Organic Compounds concentrations in indoor air tend to be higher than the level allowed by the standards or codes. Photocatalytic oxidation by employing UV radiation is a promising approach for the VOCs removal .The purpose of this paper is the development of a simple but effective model of photocatalytic oxidation air cleaner.With that model, the design and the selection of suitable photooxidation air cleaners and the measurement of their Volatile Oragnic Compounds removing effect can be easily conducted..

This article describes a new system developed and patented by a Belgian firm for air purification, using photocatalysis (UVA radiation + titania dioxide) for VOC and odour removal. Results from degradation tests are presented.