It has long been known that ventilation is a costeffective method to lower respirable dust concentrations in all types of mining applications. The National Institute for Occupational Safety and Health has been working on a number of different research techniques that use ventilation as a critical component to lower respirable dust levels at surface and metal/nonmetal operations in the United St...

This study aims at estimating variability in exposure to respirable dust and assessing whether the a priori grouping by job team is appropriate for an exposure-response study on respiratory effects among workers in a manually operated coal mine in Tanzania. Furthermore, estimated exposure levels were used to calculate cumulative exposure. Full-shift personal respirable dust samples (n = 204) we...

Chest x rays, smoking histories, and pulmonary function tests were obtained for 171 men employed in the manufacturing of silicon carbide. A lifetime exposure to respirable particulates (organic and inorganic fractions) and sulphur dioxide was estimated for each worker. Chest x ray abnormalities were related to respirable particulates (round opacities) and to age and smoking (linear opacities). ...

it is very important to determine the stable nitrogen isotope ratio for the nitrogenous substances in aerosols and the geochemistry behavior of stable nitrate ion isotopes in aerosols in order to elucidate the chemical and physical functions of clouds. hence, aerosol field sampling was conducted in the skies offshore from malibu beach and santa barbara, california, u.s.a. on 16 and 18 july 200...

it is very important to determine the stable nitrogen isotope ratio for the nitrogenous substances in aerosols and the geochemistry behavior of stable nitrate ion isotopes in aerosols in order to elucidate the chemical and physical functions of clouds. hence, aerosol field sampling was conducted in the skies offshore from malibu beach and santa barbara, california, u.s.a. on 16 and 18 july 2009...

The concentrations in the air of total and of respirable (less than 7 microns equivalent diameter) dust were measured in 142 workrooms of 17 Northern Ireland flax spinning mills using a hexhlet air sampler. Neither the distribution of total nor of respirable dust concentrations (mg./100 m.3 air) measured in each of four large workrooms conformed to the normal (or Gaussian) distribution, but it ...

Omar Bagasra, Mohammed Alsayari, Rebecca Bullard-Dillard and Mohamed A Daw (1) Department of Biology, South Carolina Center for Biotechnology and Department Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina. (2) Department of Biology, Claflin University (3) Department of Medical Microbiology and Immunology, Faculty of Medicine, Al-Fateh University, Tripoli...

This paper describes separation performance of newly developed forward cyclones with 7 kinds size and structure. The have 2 or 4 tangential-air-inlets, a dust pot flow receiver for fine particles. Our previous study showed that the had sharp PM2.5 but did not clarify mechanism. Size characteristics were evaluated using pair optical particle counters test aerosols standard polystyrene latex part...