Particulate matter reduction efficiency analysis of sprinkler system as targeted control measures for construction activity.

Air pollution caused by the construction industry in the form of particulate matter (PM) has increased to an alarming level. The effects on the health of construction workers are found to be hazardous despite the current advancement in construction methods and practices. In particular, the efficiency of existing control measures for reducing PM from various construction activities has not been improved to the desired level. This study investigated the factors that influence the efficiency of a sprinkler system-based control measure when water spraying and dust suppressant solutions are used. The real-time PM exposure was measured during hollow-block cutting activity using Alphanese OPC-N3 sensors in dust chamber. The dust suppressant suppresses dust particles by initially forming a solidified film on the particle surface, and the high cohesion of this film enhances the suppression rate by promoting dust particle coagulation. It was observed that when using a dust suppressant, the PM concentration at 100 bar exceeded concentrations at other pressures, resulting in increased efficacy in reducing PM10. Additionally, water spraying at 115 bar was determined to be the optimal control measure for achieving a significant percentage of PM reduction in a shorter period. These findings can be highly beneficial if the water sprinkler system can be modified into a smart mobility-based sprinkler system either ground-based or drone-based at construction sites in improving PM reduction efficiency particularly on high PM emitting activities.

A review on health risk assessment of PM in the construction industry - Current situation and future directions.

Particulate matter (PM) is one of the primary pollutants of the environment. The amount of PM discharged from construction projects is considerably high; it generates 70-80% of the overall PM. The composition of PM is complex and may contain various toxic substances that have severe health effects on human health. Existing health risk assessment in the construction industry lacks the efficiency to reduce the risk level of PM exposure. This study systematically reviews literature in this research area to understand the primary reasons which generates PM health risk assessments. The authors reviewed health risk assessment studies in the construction industry to analyze the current situation, and then reviewed health risk assessment studies from four different industries to compare the advancement of research and outcomes in all the five industries. From the study it is understood that the area of research related to ambient air were more developed compared to those in other areas due to their sampling methods and the size of the PM studied. From the findings of the systematic review, it is understood that majority of the risk assessment studies still rely on a two decade-old system and neglect recent research findings pertaining inhalation rate and size of PM. To overcome this, the level of risk involved in various common construction activities needs to be explored using real-time location-based PM monitoring and real-time inhalation monitoring methods. The findings of this review will help researchers gain a better perspective while conducting occupational health risk studies in the construction industry.

Data on different sized particulate matter concentration produced from a construction activity.

Particulate matter (PM) exposure is produced during most of the construction activities. The dataset was acquired from an experimental investigation by monitoring PM10, PM2.5, and PM1 concentration produced while building a solid concrete block wall. Alphasense OPC-N2 sensors and Sharp GP2Y1010 sensors were collocated in each of the monitoring stations (MS) to measure the PM concentration. The data was collected at 2 s time interval during the entire 40 min of the activity. The data can be utilized for study PM produced and propagated from construction. Furthermore, the dataset can be used to improve the awareness of the construction professionals about the PM production and exposure during the construction works and refine the current construction practices.

Meta-analysis of outcomes of endoscopic ultrasound-guided gallbladder drainage versus percutaneous cholecystostomy for the management of acute cholecystitis.

BACKGROUND: Endoscopic ultrasound-guided gallbladder drainage is a novel method of treating acute cholecystitis in patients deemed too high risk for surgery. It involves endoscopic stent placement between the gallbladder and the alimentary tract to internally drain the infection and is an alternative to percutaneous cholecystostomy (PC). This meta-analysis assesses the clinical outcomes of high-risk patients undergoing endoscopic drainage with an acute cholecystoenterostomy (ACE) compared with PC in acute cholecystitis. METHODS: A literature search was performed using the preferred reporting items for systematic reviews and meta-analyses guidelines. Databases were searched for studies reporting outcomes of patients undergoing ACE or PC. Results were reported as mean differences or pooled odds ratios (OR) with 95% confidence intervals (95% CI). RESULTS: A total of 1593 citations were reviewed; five studies comprising 495 patients were ultimately selected for analysis. There were no differences in technical or clinical success rates between the two groups on pooled meta-analysis. ACE had significantly lower post-procedural pain scores (mean difference - 3.0, 95% CI - 2.3 to - 3.6, p < 0.001, on a 10-point pain scale). There were no statistically significant differences in procedure complications between groups. Re-intervention rates were significantly higher in the PC group (OR 4.3, 95% CI 2.0-9.3, p < 0.001). CONCLUSION: ACE is a promising alternative to PC in high-risk patients with acute cholecystitis, with equivalent success rates, improved pain scores and lower re-intervention rates, without the morbidities associated with external drainage.