Tolerable Risk for Hydrogen Sulfide in Sewage Treatment Plant- STP

Hydrogen sulphide is a toxic gas, it can cause a range of physiological responses from simple annoyance to permanent injury and death. There are a number of approaches to deal with the impacts of toxic gases. This study focused on minimizing the hazard exposure for hydrogen sulfide in the different operational zones for activated sludge process in sewage waterplant. Research tools/ approaches conducted were interviews, toxic gas testers, analysis report interpretation & quantitative risk assessment method. The study was conducted on Arabian Peninsula during the period (September 2019- September 2021). The (13) operational locations tested for toxic gas concentrations were inlet chamber, outlet channel, coarse /fine screens, primary sedimentation tank, activated sludge tanks, secondary sedimentation tanks, gas desulfurization unit, disc filters, chlorine dosing unit, sludge dewatering, sludge silos and digester tanks. The study found that the highest concentration for H₂S in the inlet chamber/ outlet channel. The severity hazards in the sewage treatment plant using activated sludge process are the asphyxiation by H₂S was extremely high can cause harm to public health, followed by the radiation hazard followed by electrical hazard, then (working at height, mechanical, traffic, health, chemical, physical, ergonomic, environmental, microbial and natural). The frequency of hazards occurrence is asphyxiation by H₂S was extremely high followed by the radiation hazard and health hazard including the infection with Covid 19 virus followed by mechanical hazard then (electrical, traffic, ergonomic, natural, chemical, physical and natural). Control measures were recommended to minimize the risk of asphyxiation by H₂S in the working environment at the STP.

A Major Challenges Advanced Underground Drainage Monitoring and Automatic Rescue System using Internet of Things

In this project, An Advanced Underground Drainage Monitoring And Automatic Rescue System using Internet of Things is proposed to protect the sanitation workers form health issues. In India sewage can be cleaned from manholes and drains are a difficult and risky task for anyone, but these people/workers are forced to do these jobs just to earn for their family economy. In order to overcome this issues, a new device is proposed to monitor the human health while entering into the sewage and provide the health parameters in the real time to the officials outside or the control room. Particularly, blood pressure of sanitation workers and toxic gas level of drainage is monitored using this new proposed rescue system. The main component of this system is Arduino controller. There are three types of sensors such as Toxic gas sensor, Methane gas sensor and Ultrasonic sensor used for the proposed system. Water level indicator is used when drainage is full to find from ultrasonic sensor, SMS will be send through GSM technology. Methane Gas and Toxic gas sensor level is high, Buzzer will be ON at the same time location will be share automatically with the help of GPS. The received sensor details display on LCD at receiver with help of GSM. The performance of proposed system is compared with other existing system and shown to be more effective in terms of protect the sanitation workers from health issues.

A Study on Applying Phenol Foam Insulation Material as Pipe Lagging Material

During a fire, the major cause of casualties is the toxic gas produced from combustible interior and exterior materials. Increasing the time for occupant evacuation by reducing toxic gas is the most effective way of reducing casualties. Many casualties occurred in recent fires at the Jecheon Sports Center, Miryang Sejong Hospital, and Icheon Distribution Center. The commonality is that the toxic gas produced from combustible interior and exterior materials was the major cause of the casualties. In this study, phenol foam insulation material was considered as an alternative pipe lagging material, owing to its limited combustibility and non-production of toxic gas, to determine a method for removing the toxic gas generated from the combustion of pipe lagging material. Phenol foam insulation material is often used as the insulation material for building exteriors owing to its excellent insulation performance. Moreover, it has the advantage of being an environment-friendly product with zero ozone layer destruction coefficient and low harmful substance emissions. The incombustibility of phenol foam insulation material was verified through the Standard Performance Test of the Limited Combustible Material (Ministry of Land, Infrastructure and Transport Notice No. 2020-1053). Further, an alternative is to be proposed if a pipe lagging material with inadequate incombustibility is used in the site even though a tested pipe lagging material with limited combustibility is available.

Evaluation of Cytogenetic Alterations of Toxic Gas Exposed Population of Bhopal Having Chronic Kidney Disease

The industrial disaster of Bhopal in 1984 resulted in widespread morbidity and mortality in the vicinity of the industry and required long-term surveillance for chronic health effects in those affected by the leakage of gas. Although few cytogenetic studies were undertaken to assess genetic damage in survivors of the disaster, no studies are available on cytogenetic damage of toxic gas-exposed populations having chronic kidney disease (CKD). Thus, the present study aimed to evaluate cytogenetic alterations in chronic kidney disease patients who were exposed to leaked gas and to compare it with those who were not exposed to the leaked gas. The cytogenetic alterations were evaluated through chromosomal aberration analysis and micronuclei assay. The study included 608 study participants divided into four groups based on the history of exposure to the leaked gas and the presence or absence of CKD. The results of the study showed no statistically significant difference in cytogenetic damage between gas-exposed and non-exposed patients of CKD. However, significantly higher cytogenetic damage was observed among gas-exposed participants having CKD as compared to gas-exposed participants free from CKD. Thus, to conclude though the cytogenetic alterations were observed in an exposed group it cannot be solely attributed to the gas exposure and the role of other confounders must also be studied.

Reconfigurable Modular Platform for Prolonged Sensing of Toxic Gases in Particle Polluted Environments

The prolonged sensing of toxic gases in polluted particles and harsh environments is a challenging task that is also in high demand. In this work, the proof of principle of a sensitive, low-cost, and low-maintenance reconfigurable platform for filter-free and continuous ammonia (NH3) sensing in polluted environments is simulated. The platform can be modified for the detection of various toxic gases and includes three main modules: a microfluidic system for in-line continuous dust filtering; a toxic gas adsorption module; and a low-frequency microwave split-ring resonator (SRR). An inertia-based spiral microfluidic system has been designed and optimized through simulation for the in-line filtration of small particles from the intake air. Zeolite Y is selected as the adsorbent in the adsorption module. The adsorption module is a non-metallic thin tube that is filled with zeolite Y powder and precisely fixed at the drilled through-hole into the 3D microwave system. For the sensing module, a low-frequency three-dimensional (3D) split-ring resonator is proposed and optimally designed. A microwave resonator continuously monitors the permittivity of zeolite Y and can detect small permittivity alterations upon the presence of ammonia in the intake air. The microwave resonator is optimized at a frequency range of 2.5–3 GHz toward the detection of ammonia under different ammonia concentrations from 400 to 2800 ppm. The microwave simulation results show a clear contrast of around 4 MHz that shifts at 2.7 GHz for 400 ppm ammonia concentration. The results show the proof of principle of the proposed microfluidic-microwave platform for toxic gas detection.

Evaluation of cytogenetic alterations of toxic gas exposed population of Bhopal having chronic kidney disease

The industrial disaster of Bhopal in 1984 resulted into widespread morbidity and mortality in the vicinity of the industry and required long term surveillance for chronic health effects in those affected by the leakage of gas. Although few cytogenetic studies were undertaken to assess genetic damage in survivors of the disaster, no studies are available on cytogenetic damage of toxic gas exposed population having chronic kidney disease (CKD).Thus, the present study aimed to evaluate cytogenetic alterations in chronic kidney disease patients who wereexposed to leaked gas and to compare it with those who were not exposed to the leaked gas. The cytogenetic alterations were evaluated through chromosomal aberration analysis and micronuclei assay. The study included 608 study participants divided into four groups on the basis of history of exposure to the leaked gas and presence or absence of CKD. The results of the study showed no statistically significant difference in cytogenetic damagebetween gas exposed and non-exposed patients of CKD. However, significantly higher cytogenetic damage was observed among gas exposed participants having CKD as compared to gas exposed participants free from CKD.Thus, to conclude though the cytogenetic alterations were observed in exposed group it cannot be solely attributed to the gas exposure and the role of other confounders must also be studied.