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The use of unverified models for risk estimates and policy recommendations can be highly misleading, as their predictions may not reflect real-world health impacts. For example, a recent article states that NO2 from gas stoves “likely causes ∼50,000 cases of current pediatric asthma from long-term NO2 exposure alone” annually in the United States. This explicitly causal claim, which is contrary to several methodology and review articles published in this journal, among others, reflects both (a) An unverified modeling assumption that pediatric asthma burden is approximately proportional to NO2; and (b) An unverified causal assumption that the assumed proportionality between exposure and response is causal. The article is devoid of any causal analysis showing that these assumptions are likely to be true. It does not show that reducing NO2 exposure from gas stoves would reduce pediatric asthma risk. Its key references report no significant associations – let alone causation – between NO2 and pediatric asthma. Thus, the underlying data suggests that the number of pediatric asthma cases caused by gas stoves in the United States is indistinguishable from zero. This highlights the need to rigorously validate modeling assumptions and causal claims in public health risk assessments to ensure scientifically sound foundations for policy decisions.

Several recent news stories have alarmed many politicians and members of the public by reporting that indoor air pollution from gas stoves causes about 13% of childhood asthma in the United States. Research on the reproducibility and trustworthiness of epidemiological risk assessments has identified a number of common questionable research practices (QRPs) that should be avoided to draw sound causal conclusions from epidemiological data. Examples of such QRPs include claiming causation without using study designs or data analyses that allow valid causal inferences; generalizing or transporting risk estimates based on data for specific populations, time periods, and locations to different ones without accounting for differences in the study and target populations; claiming causation without discussing or quantitatively correcting for confounding, external validity bias, or other biases; and not mentioning or resolving contradictory evidence. We examine the recently estimated gas stove-childhood asthma associations from the perspective of these QRPs and conclude that it exemplifies all of them. The quantitative claim that about 13% of childhood asthma in the United States could be prevented by reducing exposure to gas stove pollution is not supported by the data collected or by the measures of association (Population Attributable Fractions) used to analyze the data. The qualitative finding that reducing exposure to gas stove pollution would reduce the burden of childhood asthma in the United States has no demonstrated validity. Systematically checking how and whether QRPs have been addressed before reporting or responding to claims that everyday exposures cause substantial harm to health might reduce social amplification of perceived risks based on QRPs and help to improve the credibility and trustworthiness of published epidemiological risk assessments.

Triple-crossover randomized controlled intervention trial to test whether reduced exposure to household NO2 or fine particles results in reduced symptoms among children with persistent asthma. Children (n = 126) aged 5–11 years with persistent asthma living in homes with gas stoves and levels of NO2 15 ppb or greater recruited in Connecticut and Massachusetts (2015–2019) participated in an intervention involving three air cleaners configured for: (1) NO2 reduction: sham particle filtration and real NO2 scrubbing; (2) particle filtration: HEPA filter and sham NO2 scrubbing; (3) control: sham particle filtration and sham NO2 scrubbing. Air cleaners were randomly assigned for 5-week treatment periods using a three-arm crossover design. Outcome was number of asthma symptom-days during final 14 days of treatment. Treatment effects were assessed using repeated measures, linear mixed models. Measured NO2 was lower (by 4 ppb, p <.0001) for NO2-reducing compared to control or particle-reducing treatments. NO2-reducing treatment did not reduce asthma morbidity compared to control. In analysis controlling for measured NO2, there were 1.8 (95% CI −0.3 to 3.9, p =.10) fewer symptom days out of 14 in the particle-reducing treatment compared to control. It remains unknown if using an air cleaner alone can achieve levels of NO2 reduction large enough to observe reductions in asthma symptoms. We observed that in small, urban homes with gas stoves, modest reductions in asthma symptoms occurred using air cleaners that remove fine particles. An intervention targeting exposures to both NO2 and fine particles is complicated and further research is warranted. NCT02258893. [ABSTRACT FROM AUTHOR]

The article reports on a legal dispute in Paraguay related to the word "tatakua," which is the name of a traditional oven used in the country. The conflict arose when artisans who were not part of an association began to make and sell portable tatakua ovens, which led to a complaint of misappropriation. The National Secretariat of Culture declared the knowledge and crafting techniques of Ñai’ûpo (ceramics) as National Intangible Cultural Heritage. The Public Ministry requested the dismissal of the case due to lack of crime, and the Intellectual Property Office rejected the registration application submitted for the portable "tatakua" oven as a model and industrial design. [Extracted from the article]

The use of unverified models for risk estimates and policy recommendations can be highly misleading, as their predictions may not reflect real-world health impacts. For example, a recent article states that NO 2 from gas stoves "likely causes ∼50,000 cases of current pediatric asthma from long-term NO 2 exposure alone" annually in the United States. This explicitly causal claim, which is contrary to several methodology and review articles published in this journal, among others, reflects both (a) An unverified modeling assumption that pediatric asthma burden is approximately proportional to NO 2 ; and (b) An unverified causal assumption that the assumed proportionality between exposure and response is causal. The article is devoid of any causal analysis showing that these assumptions are likely to be true. It does not show that reducing NO 2 exposure from gas stoves would reduce pediatric asthma risk. Its key references report no significant associations - let alone causation - between NO 2 and pediatric asthma. Thus, the underlying data suggests that the number of pediatric asthma cases caused by gas stoves in the United States is indistinguishable from zero. This highlights the need to rigorously validate modeling assumptions and causal claims in public health risk assessments to ensure scientifically sound foundations for policy decisions., Competing Interests: I declare no competing interests that could influence the work presented in this manuscript. Funding for this work was provided by Cox Associates, LLC. Cox Associates has reasonable expectation of receiving funds in the future from the American Gas Association (AGA) to cover part of the cost of writing up these comments and/or defraying open access charges. Cox Associates has also previously received support from the 10.13039/100000199United States Department of Agriculture (USDA) for research on statistical methods for causal analysis of observational and interventional data. The author has previously received support from the USEPA for a part of the work related to duties related to NAAQS reviews. The research questions, methods, and conclusions are solely those of the author and do not necessarily reflect the views of any funding organizations., (© 2024 The Author.)

In this narrative review, we summarize the literature and provide updates on recent studies of air pollution exposures and child lung function and lung function growth. We include exposures to outdoor air pollutants that are monitored and regulated through air quality standards, and air pollutants that are not routinely monitored or directly regulated, including wildfires, indoor biomass and coal burning, gas and wood stove use, and volatile organic compounds. Included is a more systematic review of the recent literature on long-term air pollution and child lung function because this is an indicator of future adult respiratory health and exposure assessment tools have improved dramatically in recent years. We present "summary observations" and "knowledge gaps." We end by discussing what is known about what can be done at the individual/household, local/regional, and national levels to overcome structural impediments, reduce air pollution exposures, and improve child lung function. We found a large literature on adverse air pollution effects on children's lung function level and growth; however, many questions remain. Important areas needing further research include whether early-life effects are fixed or reversible; and what are windows of increased susceptibility, long-term effects of repeated wildfire events, and effects of air quality interventions. [ABSTRACT FROM AUTHOR]

The Primary aim of the stove is to minimize the ill effects and accidents in every kitchen. This project is economical to produce & assemble, which may be readily available. This Fabrication system can be used in school and college canteens, homes, and hospitals. Our work consists of MQ2 gas Sensor, Arduino board, DC gear motor along with gas stove. Gas monitoring sensor detects the leakage of the percentage of the gas and properly sends signal / Feed back to the attached high accuracy Arduino / electronics board. The Arduino board is programmed to actuate the DC motor which runs the gas knob off so we have to monitor that leakage of the gas is to be prevented and gas accidents are reduced. It also adds ease to cooking zone which helps to reduce concentration on cooking zone. Features to avoid milk spilling, cooker whistle counting and timer are added to enhance the ease of cooking. It makes every activity related to stove with more ease and highly safe. These modes are activated with the help of temperature sensor and limit-switches. This paper deals about the Design and Fabrication of Intelligent Gas Stove for Indian women safety. [ABSTRACT FROM AUTHOR]

Residential kitchens with gas stoves are unique spaces inside dwellings.Occupants directly exposed to the combustion products and thermal effects of the stove. Applying a general model with the knowledge of describing parameters, designer could taken thermal aspects also into consideration in order to provide a save, healthy and comfortable environment in residential kitchens and homes. The aim of this study to develop this model and a new ventilation method. Results of field studies shows disadvantageous effect of kitchen exhaust unit during the operation of oven. However turbulence intensity was decreased from 123% to 25% , indoor temperature was increased by 3,7K in the occupied zone due to the forced air movement. PMV index remained within the recommended intervals (between -1,0 and +1.9), therefore it could be applied to evaulate thermal environment aroun the residential gas stove. Unpleasent effect of draught is not expected. [ABSTRACT FROM AUTHOR]

Cooking is the main source of ultrafine particles (UFP) in homes. This study investigated the effect of venting range hood flow rate on size-resolved UFP concentrations from gas stove cooking. The same cooking protocol was conducted 60 times using three venting range hoods operated at six flow rates in twin research houses. Size-resolved particle (10-420 nm) concentrations were monitored using a NanoScan scanning mobility particle sizer (SMPS) from 15 min before cooking to 3 h after the cooking had stopped. Cooking increased the background total UFP number concentrations to 1.3 × 103 particles/cm3 on average, with a mean exposure-relevant source strength of 1.8 × 1012 particles/min. Total particle peak reductions ranged from 25% at the lowest fan flow rate of 36 L/s to 98% at the highest rate of 146 L/s. During the operation of a venting range hood, particle removal by deposition was less significant compared to the increasing air exchange rate driven by exhaust ventilation. Exposure to total particles due to cooking varied from 0.9 to 5.8 × 104 particles/cm3·h, 3 h after cooking ended. Compared to the 36 L/s range hood, higher flow rates of 120 and 146 L/s reduced the first-hour post-cooking exposure by 76% and 85%, respectively. © 2018 Crown Copyright. Published with license by Taylor & Francis Group, LLC [ABSTRACT FROM AUTHOR]

Conditional cash transfers (CCTs)—cash payments provided to households or specific household members who meet defined conditions or fulfill certain behaviors—have been extensively used in India to encourage antenatal care, institutional delivery, and vaccination. This paper describes the social design and technical development of a low-cost, meal-counting stove use monitor (the Pink Key) that enables a CCT based on liquefied petroleum gas (LPG) usage and presents pilot data from its testing and the initial deployment. The system consists of a sensing harness attached to a two-burner LPG stove and an easily removable datalogger. For each cooking event with LPG, households receive 2 rupees—less than the cost of fuel, but enough to partially defray LPG refill costs. The system could enable innovative “self-monitoring” at a large scale—participants initiate the CCT by bringing their Pink Key to antenatal clinic visits, where care providers download data and initiate payments, and participants return the sensor to their stove at home. The system aligns with existing Indian programs to improve health among poor, pregnant women, and contributes a new method to encourage the use of clean cooking technologies. [ABSTRACT FROM AUTHOR]

Household air pollution (HAP) is a leading cause of morbidity and mortality worldwide. To limit HAP exposure and environmental degradation from biomass fuel use, the Government of Ghana promotes liquefied petroleum gas (LPG) use in rural Ghana via the Rural LPG program (RLP). We assessed the experiences of the RLP in 2015, 2 years after its launch. A mixed methods approach was used involving Focus Group Discussions (19) and in-depth interviews (25). In addition, a survey questionnaire was administered to elicit socio-demographic characteristics, household cooking practices and stove use patterns of 200 randomly selected respondents. At about 9 months after LPG acquisition, < 5% of LPG beneficiaries used their stoves. Some of the reasons ascribed to the low usage of the LPG cookstoves were financial constraints, distance to LPG filling point and fear of burns. Community members appreciate the convenience of using LPG. Our results underscore a need for innovative funding mechanisms contextualized within an overall economic empowerment of rural folks to encourage sustained LPG use. It emphasizes the need for innovative accessibility interventions. This could include establishing new LPG filling stations in RLP beneficiary districts to overcome the barriers to sustained LPG use. [ABSTRACT FROM AUTHOR]

Household air pollution is the sixth leading risk factor for premature mortality in Guatemala. Households in Guatemala are gradually adopting liquefied petroleum gas (LPG) stoves, but a strong tradition of woodstove use persists. We conducted a mixed-methods study of LPG stove use in peri-urban Guatemala. We used knowledge, attitudes and practices surveys with 187 LPG stove owners who also used woodstoves to identify perceptions of stove and cooking practices. Barriers to sustained use of LPG stoves were evaluated through focus groups, participant observations with stove users, and key informant interviews with community leaders. Seven themes emerged that explain household decisions to use LPG stoves: (1) The “new technology” should be framed in terms of what the “old technology” lacks, (2) income is not a predictor of gas stove acquisition but may predict sustained use, (3) men are key decision-makers but messages about LPG do not target them, (4) when stoves are viewed as “prize possessions” they may not be used, (5) collective fear about gas stoves is not based on personal experience, but on “stories we hear,” (6) sustained LPG use is hampered by two major factors, seasonally available wood and LPG retailers who are perceived as dishonest, and (7) wood fuel collection is a time to enjoy the company of friends and family and is not “drudgery.” National policies should promote the use of clean cookstove technologies in peri-urban and rapidly urbanizing areas in Guatemala where LPG stoves are in use, but used intermittently, instead of the current plan to install 100,000 “improved” woodstoves by 2032. This could be done by improving dependable cylinder distribution services, targeting gas safety and promoting positive health messages that appeal to men, as well as women. [ABSTRACT FROM AUTHOR]

Indoor air pollution (IAP) originating from firewood used as cooking fuel relates to respiratory problems and can generate economic losses. IAP is associated with 1.6 million deaths worldwide annually. We assess the mechanisms behind the cooking fuel choice – in particular, firewood or LPG –, if the exposure to IAP due to firewood usage causes respiratory problems, and if this has implications for the probability to participate in the labor market. A small economic-theoretical model is proposed in which an individual maximizes utility generated by the fuel choice, consumption, health status, and the time dedicated to health and leisure, under financial and time constraints. For an empirical test, we use the 2002 Mexican Family Life Survey (MxFLS), estimating a trivariate recursive probit model. Our study finds that the usage of firewood as the household's fuel for cooking results in an increased prevalence of respiratory problems among women (but not among men), probably related to the traditional duties in the household. In the labor participation decision, we find a negative impact of respiratory problems on participation; hence, especially for women we find a strong causal channel from exposure to IAP to health problems to a reduction of labor force participation. A possible policy to break the circle of negative effects could involve the provision of improved firewood or LPG stoves that provoke less pollution and therefore reduces the health risks. [ABSTRACT FROM AUTHOR]

Black carbon (BC) emissions from household cookstoves consuming solid fuel produce approximately 25 percent of total anthropogenic BC emissions. The short atmospheric lifetime of BC means that reducing BC emissions would result in a faster climate response than mitigating CO 2 and other long-lived greenhouse gases. This study presents the results of optical BC measurements of two new cookstove emissions field assessments and 17 archived cookstove datasets. BC was determined from attenuation of 880 nm light, which is strongly absorbed by BC, and linearly related between 1 and 125 attenuation units. A relationship was experimentally determined correlating BC mass deposition on quartz filters determined via thermal optical analysis (TOA) and on PTFE and quartz filters using transmissometry, yielding an attenuation cross-section (σ ATN ) for both filter media types. σ ATN relates TOA measurements to optical measurements on PTFE and quartz (σ ATN(PTFE) = 13.7 cm −2 μg, R 2 = 0.87, σ ATN(Quartz) = 15.6 cm −2 μg, R 2 = 0.87). These filter-specific σ ATN , optical measurements of archived filters were used to determine BC emission factors and the fraction of particulate matter (PM) in the form of black carbon (BC/PM). The 19 stoves measured fell into five stove classes; simple wood, rocket, advanced biomass, simple charcoal, and advanced charcoal. Advanced biomass stoves include forced- and natural-draft gasifiers which use wood or biomass pellets as fuel. Of these classes, the simple wood and rocket stoves demonstrated the highest median BC emission factors, ranging from 0.051 to 0.14 g MJ −1 . The lowest BC emission factors were seen in charcoal stoves, which corresponds to the generally low PM emission factors observed during charcoal combustion, ranging from 0.0084 to 0.014 g MJ −1 . The advanced biomass stoves generally showed an improvement in BC emissions factors compared to simple wood and rocket stoves, ranging from 0.0031 to 0.071 g MJ −1 . BC/PM ratios were highest for the advanced and rocket stoves. Potential relative climate impacts were estimated by converting aerosol emissions to CO 2 -equivalent, and suggest that some advanced stove/fuel combinations could provide substantial climate benefits. [ABSTRACT FROM AUTHOR]

Background: Biomass fuel smoke is a leading risk factor for the burden of disease worldwide. International campaigns are promoting the widespread adoption of liquefied petroleum gas (LPG) in resource-limited settings. However, it is unclear if the introduction and use of LPG stoves, in settings where biomass fuels are used daily, reduces pollution concentration exposure, improves health outcomes, or how cultural and social barriers influence the exclusive adoption of LPG stoves.Methods: We will conduct a randomized controlled, field intervention trial of LPG stoves and fuel distribution in rural Puno, Peru, in which we will enroll 180 female participants aged 25-64 years and follow them for 2 years. After enrollment, we will collect information on sociodemographic characteristics, household characteristics, and cooking practices. During the first year of the study, LPG stoves and fuel tanks will be delivered to the homes of 90 intervention participants. During the second year, participants in the intervention arm will keep their LPG stoves, but the gas supply will stop. Control participants will receive LPG stoves and vouchers to obtain free fuel from distributors at the beginning of the second year, but gas will not be delivered. Starting at baseline, we will collect longitudinal measurements of respiratory symptoms, pulmonary function, blood pressure, endothelial function, carotid artery intima-media thickness, 24-h dietary recalls, exhaled carbon monoxide, quality-of-life indicators, and stove-use behaviors. Environmental exposure assessments will occur six times over the 2-year follow-up period, consisting of 48-h personal exposure and kitchen concentration measurements of fine particulate matter and carbon monoxide, and 48-h kitchen concentrations of nitrogen dioxide for a subset of 100 participants.Discussion: Findings from this study will allow us to better understand behavioral patterns, environmental exposures, and cardiovascular and pulmonary outcomes resulting from the adoption of LPG stoves. If this trial indicates that LPG stoves are a feasible and effective way to reduce household air pollution and improve health, it will provide important information to support widespread adoption of LPG fuel as a strategy to reduce the global burden of disease.Trial Registration: ClinicalTrials.gov, ID: NCT02994680 , Cardiopulmonary Outcomes and Household Air Pollution (CHAP) Trial. Registered on 28 November 2016. [ABSTRACT FROM AUTHOR]

Exposure to nitrogen dioxide (NO 2 ), a byproduct of combustion, is associated with poor asthma control in children. We sought to determine whether gas-fueled kitchen appliance use is associated with 24-h indoor NO 2 concentrations and whether these concentrations are associated with asthma morbidity in children. Children aged 5–12 years old with asthma were eligible. Mean 24-h NO 2 concentration was measured in the kitchen over a four-day sampling period and gas stove use was captured in time activity diaries. The relationship between stove and oven use and daily NO 2 concentration was analyzed. Longitudinal analysis assessed the effect of daily NO 2 exposure on symptoms, inhaler use, and lung function. Multivariate models were adjusted for age, sex, season, and maternal education. Thirty children contributed 126 participant days of sampling. Mean indoor 24-h NO 2 concentration was 58(48) ppb with a median (range) of 45(12–276) ppb. All homes had gas stoves and furnaces. Each hour of kitchen appliance use was associated with an 18 ppb increase in 24-h NO 2 concentration. In longitudinal multivariate analysis, each ten-fold increase in previous-day NO 2 was associated with increased nighttime inhaler use (OR = 4.9, p = 0.04). There were no associations between NO 2 and lung function or asthma symptoms. Higher previous-day 24-h concentration of NO 2 is associated with increased nighttime inhaler use in children with asthma. [ABSTRACT FROM AUTHOR]

The Galapagos Islands are a fragile ecosystem, which belongs to Ecuador country. The supply of energy is through of combined technologies such as thermal, photovoltaic and wind. The government of Ecuador is fostering the policy zero CO 2 emissions within the islands. In order to achieve this objective, some initiatives are carried out like replacing the conventional vehicles and the gas stoves by electrical ones. Taking into account this framework, it becomes vital to assess the impact of these new policies on the distribution network; for sure, this will change significantly the operation and control of Galapagos distribution grid. In addition, once determined the impact it is worth proposing smart strategies in order to deal with the load growth due to new services. Thus, this paper proposes an adapted and intelligent method for performing Demand Side Management in the Galapagos low voltage network, the proposal executes Demand Response in the presence of time of use pricing. An ingenious approach, which consists in modifying load curves by means of polynomial functions is presented; several scenarios with different strategies are analyzed, the main results show as the proposal strategy respect all the limits stablished by the regulator and as the rebound effect is annulated. Real field information has been used in the presented models. [ABSTRACT FROM AUTHOR]

REACCTING (Research on Emissions Air Quality, Climate, and Cooking Technologies in Northern Ghana) was a 200-home cookstove intervention study from 2013 to 2015. Study households were divided into four groups: a control group, a group given two locally made rocket stoves, a group given two Philips forced draft stoves, and a group given a locally made rocket stove and a Philips stove. In a subset of study households, 48-hour PM 2.5 exposure samples were collected for adults and children, as well as in the primary cooking area. Further, weekly ambient background PM 2.5 samples were collected for the first nine months of the study. All PM 2.5 samples were analyzed for elemental and organic carbon (EC/OC), and a subset was also analyzed for organics. Mixed effects modeling was applied to quantify differences in PM exposures between the groups and to assess relationships between exposures and cooking area measurements. Results showed that personal OC exposure for the intervention groups was 56.6% lower than the control group ( p ≤ 0.01). Both intervention groups given Philips stoves had significantly lower EC exposure than the control group (60.6% reduction, p ≤ 0.02). Only weak relationships were found between personal and cooking area EC or OC. Source apportionment modeling was performed on both the personal/microenvironment and the ambient organics PM 2.5 data sets to assess the sources of the observed PM. We identified six PM sources. The identified source factors were similar among the data sets, as well as with previous work in Navrongo. Two sources, one characterized by the presence of methoxyphenols, and one by the presence of polyaromatic hydrocarbons and EC, were associated with biomass burning, and accounted for a median of 9.2% of OC and 15.3% of EC personal exposure. Here, we demonstrate the utility of using the cooking-related source apportionment factors within a mixed effects model for more precise estimation of exposures due to cooking, rather than other combustion sources unrelated to the intervention. [ABSTRACT FROM AUTHOR]

Exposure pathways to the carcinogen benzene are well-established from tobacco smoke, oil and gas development, refining, gasoline pumping, and gasoline and diesel combustion. Combustion has also been linked to the formation of nitrogen dioxide, carbon monoxide, and formaldehyde indoors from gas stoves. To our knowledge, however, no research has quantified the formation of benzene indoors from gas combustion by stoves. Across 87 homes in California and Colorado, natural gas and propane combustion emitted detectable and repeatable levels of benzene that in some homes raised indoor benzene concentrations above well-established health benchmarks. Mean benzene emissions from gas and propane burners on high and ovens set to 350 °F ranged from 2.8 to 6.5 μg min -1 , 10 to 25 times higher than emissions from electric coil and radiant alternatives; neither induction stoves nor the food being cooked emitted detectable benzene. Benzene produced by gas and propane stoves also migrated throughout homes, in some cases elevating bedroom benzene concentrations above chronic health benchmarks for hours after the stove was turned off. Combustion of gas and propane from stoves may be a substantial benzene exposure pathway and can reduce indoor air quality.

Objective: Patients with obsessive-compulsive disorder (OCD) typically report to have "not just right experiences" (NJRE). Up till now it is unclear which behavioral OCD features may give rise to NJREs. We used an induced checking paradigm to experimentally study whether perseverative checking elicits NJREs. Method: Two experiments separately tested this hypothesis among n = 48 (Experiment I) and n = 55 (Experiment II) healthy participants. We used a virtual checking task, in which participants either checked gas stoves or light bulbs. All participants started and ended with a trial in which they checked a gas stove (i.e., pre- and post-test). In between, the experimental group repeatedly checked the gas stove (i.e., relevant checking), while the control group repeatedly checked light bulbs (i.e., irrelevant checking). At pre- and post-test, all participants answered questions about the corresponding gas stove checking trial (i.e., memory confidence, vividness and details) and rated their level of NJRE. Results: In line with previous research, both experiments showed that relevant checking (as opposed to irrelevant checking) resulted in reduced memory confidence and less vivid and detailed recollections of the last checking trial. Most importantly, both studies found a medium effect for increased NJREs after relevant checking compared to irrelevant checking. Since not all results reached statistical significance in the individual studies, we combined the findings in a meta-analysis that clearly confirmed our hypotheses. Conclusions: Data of Experiment I and II strongly suggest that repeated checking results in NJRE. [ABSTRACT FROM AUTHOR]

Lean manufacturing techniques leads to the elimination of non-value added activities in the industrial ambiance and identifies the current manufacturing procedures, processes to achieve improvement in terms of cost reduction, increase in quality and profit. Lean manufacturing tools are extensively used in industries for recognizing and eliminating the non-value added activities, aiming towards to effective utilization of resources and productivity improvement. Through this research article a study has been made by adopting lean manufacturing techniques to enhance the productivity in gas stove burner manufacturing unit by reduction of lead time. The process flow of existing system is analyzed by using visual study and time study for individual processes. The current layout for the process flow studied and the proposed layout was derived. The proposed layout has been used for successful work flow to meet the future production requirement. To minimize the material movement and reduce work in progress inventory the Kanban storage system was established. Rank position method has been used for line balancing which gives optimum resource allocation for the process based on the Tori Amos Khang Trang time. The proposed layout reduced the material movement from 97 meters to 63 meters and production had also increased by about 20%. [ABSTRACT FROM AUTHOR]

Indoor air pollution significantly influences personal exposure to air pollution and increases health risks. Nitrogen dioxide (NO) is one of the major air pollutants, and therefore it is important to properly determine indoor concentration of this pollutant considering the fact that people spend most of their time inside. The aim of this study was to assess indoor and outdoor concentration of NO during each season; for this purpose, passive sampling was applied. We analyzed homes with gas and electric stoves to determine and compare the concentrations of NO in kitchen, living room, and bedroom microenvironments (MEs). The accuracy of passive sampling was evaluated by comparing the sampling results with the data from air quality monitoring stations. The highest indoor concentration of NO was observed in kitchen ME during the winter period, the median concentration being 28.4 μg m. Indoor NO levels in homes with gas stoves were higher than outdoor levels during all seasons. The concentration of NO was by 2.5 times higher in kitchen MEs with gas stoves than with electric stoves. This study showed that the concentration of NO in indoor MEs mainly depended on the stove type used in the kitchen. Homes with gas stoves had significantly higher levels of NO in all indoor MEs compared with homes where electric stoves were used. [ABSTRACT FROM AUTHOR]

More than once, I have heated milk on a gas stove only to have it boil over disastrously. The U.S. and its allies face at least four major and converging challenges that may also boil over like overheated milk, perhaps simultaneously. Social scientists will have more sophisticated frameworks, but this homely analogy of the full gas stove frames my points. [ABSTRACT FROM AUTHOR]