Reduce Dust Levels Research Articles

Dispersion and migration characteristics of multisource respirable dust in development panels during tunnelling processes

Underground miners in Australia are facing continued threats from dust-related diseases. To address these issues, improved knowledge of airflow migration patterns and respirable dust dispersion characteristics within a continuous-miner-driven heading under an exhausting ventilation system is required. Based on site-specific conditions of a development heading in New South Wales, a three-dimensional computational fluid dynamics (CFD) model was constructed and validated with onsite dust monitoring data, where a good agreement was achieved. Three scenarios of coal cutting at the middle, floor and roof positions were considered and simulated, with dust generated at four different sources. The simulation results indicated that the operators on the left-hand-side (LHS) with the extraction duct should be equipped with fit-for-purpose personal protective equipment and stay behind the ventilation duct inlet during coal cutting process, while miners standing at the right-hand-side (RHS) of the continuous miner for roof and rib bolting and machine operating should stay immediately behind the roof and rib bolting rig where dust concentration is relatively low. In addition, an increase in airflow rate through the exhausting ventilation duct or a reduction in the distance from the duct inlet to the heading face assisted in reducing dust levels within the heading, particularly at the LHS of the continuous miners. Finally, compared to the scenario of the current ventilation scheme, an on-board exhausting ventilation system could improve dust removal performance, with dust concentration at the breathing level reducing by approximately 43.6%. This modelling study can advance the understanding of multi-source dust diffusion characteristics in the heading face and provide guidance on dust mitigation, thus improving the health and safety of miners and creating a cleaner underground working environment.

A Study on Dust-Control Technology Used for Large Mining Heights Based on the Optimization Design of a Tracking Spray Nozzle

Intense cutting-induced dust production in fully mechanized mining faces (FMMFs) with large mining heights produces a high amount of dust that is difficult to capture and severely affects the working environment, threatening the health of occupational staff. The effective spray range and atomization performance of tracking sprays are counteracted by the influences of the mine’s height and ventilation airflow in FMMFs. Thus, optimizing the spray’s parameters and relationship between the effective spray range and atomization performance to reduce dust levels is the main priority of dust-control techniques. In this study, a new swirl-core atomization nozzle is developed based on fluid mechanics and the solid–liquid coalescence mechanism. The liquid generates a circumferential velocity when passing through the swirl core, which considerably increases the droplet breaking power and reduces the droplet cohesion factor, achieving a remarkable atomization effect. The spray angle of the new nozzle is 57°, which is 80.9% greater than the GZPW-16 mine-use nozzle (31.5°); the effective spray range increases from 5.2 to 5.9 m; and the spray’s mist saturation is significantly better than the GZPW-16 mine-use nozzle. Under different test pressures, the particle size range of the droplets produced by the new nozzle and dust particles on site satisfied the best synergy of droplet–dust coalescence. The total and respirable dust-reduction rates were 78% and 75.1%, respectively, which were 42% and 65% higher than those of the original nozzle. The new nozzle effectively improves the efficiency of the single dust-control technique of the tracking spray, which is significant for the dust-prevention and -control technology of FMMFs with large mining heights.

Expression of epithelial membrane antigen and cytokeratin among Indian workers exposed to cotton fibre dust in textile industries.

In India, around 20 million workers are engaged in the textile industries. However, the prevalence of byssinosis has been little reported. To determine the prevalence of byssinosis and other respiratory disorders among workers exposed to cotton dust in textile mills in Delhi, India. Sputum samples were collected from 156 workers employed in 15 cotton textile mills, and expression of epithelial membrane antigen (EMA) and cytokeratin (CK) marker proteins was investigated. Information regarding respiratory symptoms, certain personal characteristics and occupational history was also gathered. Symptoms were observed in 56.41% of the workers. Expression of EMA and CK was observed in 27.5% and 50% of the workers, respectively. Expression of EMA and CK was significantly associated with smoking and duration of employment. Measures are needed to reduce dust levels in the workplace, and to discourage smoking and alcohol consumption among the textile workers.

The Effect of Alumunium Dust Exposure on Lung Function Disorders

Background: Industrial development continues to increase every year. CV X is a company in the manufacture of cauldrons and prickles which produce aluminum dust contaminants. Workers who work more than eight hours and lack of air exchange can affect lung function. This study aims to analyze the effect of aluminum dust exposure on lung function disorders in workers at CV X. Methods: This type of research was quantitative study with cross-sectional design. Sampling using simple random sampling technique according to inclusion and exclusion criteria with 40 respondents. Data analysis by using univariate and bivariate analysis with Chi-Square and Kolmogorov-Smirnov tests. Results: The results showed that there was no effect of aluminum dust exposure on lung function disorders (p = 0.166). However, there are 65% of workers who have lung function disorders, consists of 42.5% obstructive workers, 22.5% restrictive workers, and none of which have impaired combined lung function, while 35% of workers is normal. The majority of aluminum dust levels in the work environment are above the Threshold Value (5 mg/m3) of 72.5%. Conclusion: It is known that workers who experience obstruction problems of 51.7% are workers that exposed to aluminum dust above TLV (5 mg/m3) and there are 24.1% of workers experiencing restriction disorders exposed to aluminum dust above TLV. To prevent workers from experiencing lung function disorders due to exposure to aluminum dust, it is necessary to control efforts in the form of additional ventilation to reduce dust levels in the work environment.

Mathematical justification of the mechanism of dust deposition by electrofilters for improving working conditions of poultry farm workers

The aim of the research is to reduce the concentration of dust in poultry houses by means of dust deposition by means of electrostatic precipitators. The objectives of the study include ensuring the improvement of working conditions for workers in poultry farms by reducing the dust content of the air; analysis of methods of air purification from industrial dust in poultry buildings; proposing the most effective way to clean the air from industrial dust in poultry buildings based on the analysis of existing methods and technical means. Analysis of the existing methods and technical means for cleaning the air environment of production facilities in poultry farming revealed that the most effective devices for reducing dust levels are electrostatic precipitators based on the action of corona discharge. But currently patented electrostatic precipitators have a limited scope. This is due to the fact that electrostatic precipitators provide high efficiency of dust removal with significant overall dimensions of these devices. The technical solution to this problem is the use of cylindrical multisection electrostatic precipitators, in which all corona and collecting electrodes have the shape of a cylinder and are arranged radially, alternately following one after the other. As practical results have shown, this design cleans significant volumes of air in a better quality, without the need for reconstruction of technological equipment, expansion of production areas and freeing up additional space.

The Impact of Black Lung and a Methodology for Controlling Respirable Dust.

Coal workers' pneumoconiosis (CWP), commonly known as black lung, is caused by the inhalation of respirable coal mine dust and is a disabling and potentially fatal lung disease with no cure. Historically, CWP has taken a tremendous human and financial toll in the US coal mining industry. Recent health surveillance data indicates that CWP continues to occur at elevated levels. Respirable coal dust exposure must be controlled to prevent the development of CWP. The Pittsburgh Mining Research Division of the National Institute for Occupational Safety and Health (NIOSH) conducts laboratory and mine-site research to identify control technologies that can be used to successfully reduce respirable dust levels. Various technologies, using multiple methods of control, can be applied in order to reduce dust levels. An overview of CWP's impact and a general methodology for controlling respirable dust in underground coal mines are discussed in this paper.

MultiTex RCT \u2013 a multifaceted intervention package for protection against cotton dust exposure among textile workers \u2013 a cluster randomized controlled trial in Pakistan: study protocol

BackgroundIn the Pakistani textile industry the prevalence of workplace respiratory illnesses, including byssinosis, is high. The MultiTex RCT study aims to determine the effectiveness of a multifaceted intervention package in reducing dust levels in cotton mills, decreasing the frequency of respiratory symptoms among cotton textile workers, and improving their lung function.Methods/designWe will conduct a cluster-randomized controlled trial at 28 textile mills in Karachi. The intervention will comprise: training in occupational health for all workers and managers reinforced by regular refresher sessions; the formation of workplace committees to draw up, agree and promote a health and safety plan that includes wet mopping, safe disposal of cotton dust, and the use of simple face-masks, as well as further publicity about the risks from cotton dust; and provision of adequate supplies of face-masks to support the health and safety plan. Participating mills will be randomized to intervention and control arms following a baseline survey. The impact of the intervention will be determined through follow-up surveys conducted at 3, 12 and 18 months. Data collection in the surveys will include spirometry, questionnaire-based interviews and cotton-dust measurements.DiscussionIf successful, the study may pave the way for simple, low-cost interventions that can help reduce cotton-dust levels in textile mills, and improve the respiratory health of textile workers in developing countries such as Pakistan.Trial registrationClinicalTrials.gov, ID: NCT03738202. Registered on 12 November 2018.

Dust collection potential and air pollution tolerance indices in some young plant species in arid regions of Iran

Abstract: Dust is one of the main environmental challenges in most arid zone cities of Iran. Tree plantation and forest belts can provide a cost-effective and eco-friendly solution to mitigate dust pollution. Air pollution tolerance index (APTI) based on a combination of total chlorophyll (TChl), relative water content (RWC), ascorbic acid (AsA), and leaf pH is considered as one of the most important means for determining sensitive and tolerant plant species for greening. The present study aimed to evaluate the dust capturing efficiency and APTI of Fraxinus rotundifolia Mill., Morus alba L., Celtis caucasica Willd., and Melia azedarach L., four tree species commonly used in urban green areas of most cities in Iran. As a completely randomized design, 256 saplings were grown in four plastic sheets (64 saplings of four species in each chamber) and the dust was applied at concentrations of 0, 300, 750, and 1500 μg m-3 once a week for 70 days. The results revealed that dust accumulation was greatest in the 750 and 1500 μg m-3 treatment in the following order: M. alba > C. caucasica > F. rotundifolia > M. azedarach. In all species, pH, RWC, AsA, and TChl diminished with increasing dust concentration. A decline in APTI of 0 to 1500 μg m-3 was observed in all species. At 750 μg m-3, only M. alba was tolerant to dust and the other species were intermediate. At 1500 μg m-3, M. alba and M. azedarach showed to be intermediate while two other species were sensitive. The greatest relationship was found between APTI and RWC (R2= 0.85), followed by APTI and AsA (R2 = 0.82). Although C. caucasica showed a high capacity for dust accumulation at 1500 μg m-3, it was found to be sensitive and can, therefore, be used as a dust pollution bioindicator. F. rotundifolia and C. caucasica are not suitable for plantation in urban green spaces where dust concentration is 1500 μg m-3. M. alba appeared to be a tolerant species adaptable to arid urban environments with a potential for reducing dust levels by sinking its particles.

Application of neutral electrolyzed water spray for reducing dust levels in a layer breeding house

Reducing airborne dust is an essential process for improving hen housing environment. Dust reduction effects of neutral electrolyzed water (pH 8.2) spray were investigated in a commercial tunnel-ventilated layer breeding house during production in northern China. A multipoint sampler was used to measure airborne dust concentration to study the dust reduction effects and distribution in the house. Compared with the control treatment (without spray), airborne dust level was reduced 34% in the 3 hr after spraying 216 mL m−2 neutral electrolyzed water in the breeding house. The dust concentration was significantly higher during the periods of feed distribution (1.13 ± 0.13 mg m−3) and artificial insemination (0.72 ± 0.13 mg m−3) compared with after spray (0.47 ± 0.09 mg m−3) and during lights-off period (0.29 ± 0.08 mg m−3) in the three consecutive testing days (P < 0.05). The experimental cage area was divided into four zones along the length of the house, with zone 1 nearest to the evaporative cooling pad and zone 4 nearest to the fans. The air temperature, relative humidity, airflow rate, and dust concentration were measured at the sampling points of the four zones in 3 consecutive days and mortality of the birds for the duration of a month were investigated. The results showed that the air temperature, airflow rate, dust concentration, and number of dead birds increase from zone 1 to zone 4 in the tunnel-ventilated layer breeding house. Implications: It is difficult to effectively reduce hen house airborne dust levels and limited information is available on airborne dust distribution in tunnel-ventilated hen houses. This work investigates (i) the application of neutral electrolyzed water spray for reducing dust in a layer breeding houses; (ii) dust concentration variations in 24-hr house operation; as well as (iii) the effects of location on dust concentrations. It was demonstrated that neutral electrolyzed water spray can be efficiently used for dust reduction in poultry houses. Further, a better understanding of the dust concentration variations in 24-hr house operation and in different spatial zones can contribute to bird housing environment management and poultry house design so as to improve bird health.

Occupational lung disease in the South African mining industry: Research and policy implementation

South African miners face an epidemic of occupational lung diseases. Despite a plethora of research on the mining industry, and the gold mining industry in particular, research impact (including disease surveillance) on policy implementation and occupational health systems performance lags. We describe the gold mining environment, and research on silicosis, tuberculosis, HIV and AIDS, and compensation for occupational disease including initiatives to influence policy and thus reduce dust levels and disease. As these have been largely unsuccessful, we identify possible impediments, some common to other low- and middle-income countries, to the translation of research findings and policy initiatives into effective interventions.

A study of the occupational health function among female textile workers

Reduction of respiratory function among textile workers in the textile industry has been observed since the 1970s. A contaminant of raw cotton fiber and cotton dust, has been proposed as a affecting agent that may deteriorate the respiratory function. Present study aimed to find the factors associated with the deterioration of respiratory function among female textile workers. The sample consisted of 243 men above the age of 20 years who had worked for at least 3 months years in a textile factory and 235 female non textile workers of same area were studied. All the respondents were interviewed by a pretested questionnaire to gather information regarding the chest symptoms, certain personal characteristics and occupational history. Statistical analyses like Chi-square and odds ratio was done to determine the significant difference between female textile workers and female non textile workers. Univariate analysis of the factors for symptomatic byssinosis showed that dusty worksites, heavy smoking and duration of service years were significant. Logistic regression analysis showed that working in the scouring (odds ratio 11.0), spinning (odds ratio 4.7) and weaving sections (odds ratio 2.6), heavy smoking (odds ratio 12.4) and more than 10 years of service (odds ratio 2.8) were independent significant risk factors. Efforts to reduce dust levels in the working environment and to discourage smoking among textile workers need to be strengthened to minimize the risk of developing byssinosis. Key words: Occupational health, respiratory problems, textiles workers, non textiles workers, FEV 1.0.

Smoke and dust get in your eyes: what does it mean in the workplace?

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality in the world. UK statistics show that it is the third biggest cause of respiratory deaths, accounting...

The Effectiveness of Various Biofiltration Substrates in Removing Bacteria, Endotoxins, and Dust from Ventilation System Exhaust from a Chicken Hatchery

The objective of this study was to evaluate the effectiveness of various organic and organic-mineral biofilter media in purifying ventilation exhaust from a chicken hatchery room. Three different substrates were tested. Efficiency levels for the removal of dust, gram-negative bacteria, and bacterial endotoxin were recorded. The microbiological properties of the substrates were also studied. All of the biofilter substrates were highly effective in removing gram-negative bacteria, moderately effective in reducing dust levels, and only slightly effective in removing endotoxin. The substrate that was most efficient in retaining bioaerosols was the organic-mineral medium containing 20% halloysite, 40% compost, and 40% peat, which generally had at least satisfactory efficiency values for removing all of the contaminants tested.

Development of Performance-Based Tests for Nontraditional Road Additives

Nontraditional road additives (chemical stabilizers and dust palliatives) are applied to unsealed roads to reduce dust levels and gravel loss and improve riding quality and all-weather passability. However, the level of research conducted on additives and documentation derived from it are often unsatisfactory. A review of studies revealed that similar procedures were followed, which entailed routine laboratory tests on a locally available material, followed by a field test during which the period of effectiveness was assessed. No documented test methods exist specifically for these additives. Researchers tend to adapt methods developed for cementitious and asphaltic additives or compare before- and after-treatment results on standard indicator tests. Results rarely correlate with field performance, necessitating construction of full-scale experiments before making a decision on applying the additives on a wider scale. Invariably, a new experiment must be constructed each time conditions such as material, traffic, and climate change. A series of performance-based laboratory tests for nontraditional road additives has been developed, and results have been compared with performance in full-scale experiments. Results are compared with untreated controls or traditional stabilizers. The tests have been incorporated into a research protocol as well as a fit-for-purpose certification system for road additives. They are sensitive enough to assess performance at different application rates and to compare the performance of different additives on the same material. Tentative limits for decision making have been developed on the basis of comparisons of test results with performance on full-scale sections.

Field assessment of control techniques and long-term dust variability for surface coal mine rock drills and bulldozers

ABSTRACT Airborne respirable dust surveys were conducted at six surface coal mines to investigate the effectiveness of dust control methods used on rotary rock drills and bulldozers. Dust controls commonly used on drills include a dry dust collection system, exhausting from a shrouded area around the collared hole, and an enclosed drill operator cab, filtering airborne dust from the cab. Bulldozers are also typically equipped with an enclosed operator cab as a dust control measure. Airborne respirable dust sampling was conducted near each equipment's source of generation and inside its enclosed cab. Silica analysis was performed on the dust samples to determine the percent silica content in the dust generated at the six mining operations. An additional eight-month follow-up of dust sampling was also conducted in the enclosed operator cabs of several rock drills and bulldozers. Data were analyzed for long-term variability of accepted control methods to abate dust and silica levels. The highwall rock drill was the major and most variable dust source as compared to the bulldozer, generating dust levels, on average, one order of magnitude higher than dust levels of the bulldozer. Four of the six drills surveyed had dust containment and capture problems at the shrouded drill table above the hole. Repairs or modifications to three of the drill dust collection systems were shown to reduce dust levels by more that 50% next to the shrouded drill table. The enclosed operator cabs provided more than 90percnt; and more than 40% lower dust levels than at the dust source for the drill and bulldozer, respectively. Long-term sampling of several of these highwall drills and bulldozers showed that the dust levels in the drill cabs were frequently higher than 0.2 mg/m3 and more variable than in the bulldozers. The bulldozer dust levels were frequently below 0.2 mg/m3. Future research should focus on improving some of the deficiencies present in the drill/s primary dust collection system, and developing quality control methods to ensure the integrity of enclosed cab protection for equipment operators.

Improved nasal clearance among pulp-mill workers after the reduction of lime dust.

The purpose of this study was to investigate nasal symptoms and function among workers exposed to lime dust and to determine if a reconstruction of the workplace improved the worker's nasal health. In 1992, pulp-mill workers (N = 15) exposed to lime dust and an equal number of matched unexposed referents were examined by questionnaires, nasal peak expiratory flow, the saccharin test, nasal lavage, and a clinical examination of the upper airways. The study was repeated one year later, after the pulp mill had been rebuilt. Dust levels were measured on both occasions with stationary and personal samplings. In 1992 the total dust level was 1.2 mg.m-3. The saccharin test showed a significantly increased nasal transit time for the exposed workers in comparison with that of the unexposed referents (difference 3.5 min, 95% confidence interval 0.1-6.9 min). One year later the dust levels had decreased to 0.1 mg. m-3, and the difference in nasal transit time had decreased (difference- 0.8 min, 95% confidence interval -4.8-3.3 min). Workers exposed to lime dust have an impaired mucociliary function. This impairment is probably due to the alkalinity of the lime. When dust levels are reduced, mucociliary function improves; therefore renovating a workplace to reduce dust levels has a positive effect.

A positive, individually ventilated caging system: a local barrier system to protect both animals and personnel.

Most local barrier systems are designed primarily either to protect animals from airborne contamination (exclusion) or to ensure the safety of personnel (hazard containment). Few, other than isolators, are able to cope with the often conflicting demands to do both. The Positive Individually Ventilated system (PIV), which provides pressure adjustable, individual supply and exhaust ventilation to each cage has been tested with this in mind as well as the need to ensure that environmental conditions comply with the requirements of the Home Office Code of Practice (CoP). The results indicate that when compared with traditional open racking the system can reduce both the risk of animals becoming contaminated by airborne infection from the room and the risk of aeroallergens escaping from the cages into the room air. At the same time, environmental conditions within the cages are both less variable and less stressful to the occupants. Conditions of air temperature, relative humidity, ventilation rates, light intensity and (with appropriate air handling) sound levels, all comply with or are better than those required by the CoP. Even with the room air change rate set at only 8/h (8 ac/h) the air distribution system results in draught-free cage ventilation rates of around 50-120 ac/h. This means that with at least the PIV exhaust(s) linked directly into the air conditioning system of the building, the size of the latter and its associated running costs can be reduced by around 50%; this energy saving concept has been approved in principle by the Home Office. Additional benefits include the fact that bedding is kept much drier allowing further cost savings in bedding and associated labour costs. The system is thus beneficial to the animals in protecting them from airborne infection and other stresses. By providing a less variable environment it also helps to minimise the sort of interference with experiments which can arise from that source. Similarly, in accordance with the aims of 'The Control of Substances Hazardous to Health Regulations' (COSHH 1988) and the Health & Safety Executive (HSE 1990), by reducing dust levels in the room air, including allergens, it is also beneficial to the personnel working in the animal rooms.

Occupational health problems due to garbage sorting

Medical examinations and dust analysis showed that illness of workers, predominently asthma, in an enclosed waste sorting plant in Denmark, was probably related to high particulate levels containing bacteria and endotoxins derived from decaying waste. Modification of the plant to enclose conveyors and install vacuum cleaning systems to reduce dust levels led to significant reductions in airborne bacteria and the nearly complete elimination of endotoxins. However, fungi concentrations were not reduced.

Occupational Health Problems Due To Garbage Sorting

Medical examinations and dust analysis showed that illness of workers, predominently asthma, in an enclosed waste sorting plant in Denmark, was probably related to high particulate levels containing bacteria and endotoxins derived from decaying waste. Modification of the plant to enclose conveyors and install vacuum cleaning systems to reduce dust levels led to significant reductions in airborne bacteria and the nearly complete elimination of endotoxins. However, fungi concentrations were not reduced.

DUST CONTROL MEASURES IN DUTCH BRICKWORKS

Dust concentrations in Dutch brickworks and the efficiency of measures to reduce exposure to dust were investigated in four representative works. The project consisted of three parts. In Part 1 total and respirable dust and respirable quartz dust were measured before control measures were recommended or taken. The dust concentrations were in many cases too high; the respirable quartz dust concentration was most critical. Recommendations were made for the introduction at short notice of simple control measures and good housekeeping rules. The works were investigated again a year later to assess the effect of the recommendations (Part 2). The concentrations had decreased considerably in some cases where the recommendations were followed. Part 3 describes the experiment with nozzles that generate a fine water mist to moisten dusty surfaces and so reduce dust levels. These nozzles reduced respirable dust concentrations to 0.5 mg m−3 or less, which is acceptable.