Use Of Traditional Stoves Research Articles

Fidelity and adherence to a liquefied petroleum gas stove and fuel intervention: The multi-country Household Air Pollution Intervention Network (HAPIN) trial

BackgroundReducing household air pollution (HAP) to levels associated with health benefits requires nearly exclusive use of clean cooking fuels and abandonment of traditional biomass fuels. MethodsThe Household Air Pollution Intervention Network (HAPIN) trial randomized 3,195 pregnant women in Guatemala, India, Peru, and Rwanda to receive a liquefied petroleum gas (LPG) stove intervention (n = 1,590), with controls expected to continue cooking with biomass fuels (n = 1,605). We assessed fidelity to intervention implementation and participant adherence to the intervention starting in pregnancy through the infant’s first birthday using fuel delivery and repair records, surveys, observations, and temperature-logging stove use monitors (SUMs). ResultsFidelity and adherence to the HAPIN intervention were high. Median time required to refill LPG cylinders was 1 day (interquartile range 0–2). Although 26% (n = 410) of intervention participants reported running out of LPG at some point, the number of times was low (median: 1 day [Q1, Q3: 1, 2]) and mostly limited to the first four months of the COVID-19 pandemic. Most repairs were completed on the same day as problems were reported. Traditional stove use was observed in only 3% of observation visits, and 89% of these observations were followed up with behavioral reinforcement. According to SUMs data, intervention households used their traditional stove a median of 0.4% of all monitored days, and 81% used the traditional stove < 1 day per month. Traditional stove use was slightly higher post-COVID-19 (detected on a median [Q1, Q3] of 0.0% [0.0%, 3.4%] of days) than pre-COVID-19 (0.0% [0.0%, 1.6%] of days). There was no significant difference in intervention adherence pre- and post-birth. ConclusionFree stoves and an unlimited supply of LPG fuel delivered to participating homes combined with timely repairs, behavioral messaging, and comprehensive stove use monitoring contributed to high intervention fidelity and near-exclusive LPG use within the HAPIN trial.

Health impacts of a randomized biomass cookstove intervention in northern Ghana

BackgroundHousehold air pollution (HAP) from cooking with solid fuels has adverse health effects. REACCTING (Research on Emissions, Air quality, Climate, and Cooking Technologies in Northern Ghana) was a randomized cookstove intervention study that aimed to determine the effects of two types of “improved” biomass cookstoves on health using self-reported health symptoms and biomarkers of systemic inflammation from dried blood spots for female adult cooks and children, and anthropometric growth measures for children only.MethodsTwo hundred rural households were randomized into four different cookstove groups. Surveys and health measurements were conducted at four time points over a two-year period. Chi-square tests were conducted to determine differences in self-reported health outcomes. Linear mixed models were used to assess the effect of the stoves on inflammation biomarkers in adults and children, and to assess the z-score deviance for the anthropometric data for children.ResultsWe find some evidence that two biomarkers of oxidative stress and inflammation, serum amyloid A and C-reactive protein, decreased among adult primary cooks in the intervention groups relative to the control group. We do not find detectable impacts for any of the anthropometry variables or self-reported health.ConclusionsOverall, we conclude that the REACCTING intervention did not substantially improve the health outcomes examined here, likely due to continued use of traditional stoves, lack of evidence of particulate matter emissions reductions from “improved” stoves, and mixed results for HAP exposure reductions.Clinical trial registryClinicalTrials.gov (National Institutes of Health); Trial Registration Number: NCT04633135; Date of Registration: 11 November 2020 – Retrospectively registered.URL: https://clinicaltrials.gov/ct2/show/NCT04633135?term=NCT04633135&draw=2&rank=1

Fidelity and Adherence to a Liquefied Petroleum Gas Stove and Fuel Intervention during Gestation: The Multi-Country Household Air Pollution Intervention Network (HAPIN) Randomized Controlled Trial.

Background: Clean cookstove interventions can theoretically reduce exposure to household air pollution and benefit health, but this requires near-exclusive use of these types of stoves with the simultaneous disuse of traditional stoves. Previous cookstove trials have reported low adoption of new stoves and/or extensive continued traditional stove use. Methods: The Household Air Pollution Intervention Network (HAPIN) trial randomized 3195 pregnant women in Guatemala, India, Peru, and Rwanda to either a liquefied petroleum gas (LPG) stove and fuel intervention (n = 1590) or to a control (n = 1605). The intervention consisted of an LPG stove and two initial cylinders of LPG, free fuel refills delivered to the home, and regular behavioral messaging. We assessed intervention fidelity (delivery of the intervention as intended) and adherence (intervention use) through to the end of gestation, as relevant to the first primary health outcome of the trial: infant birth weight. Fidelity and adherence were evaluated using stove and fuel delivery records, questionnaires, visual observations, and temperature-logging stove use monitors (SUMs). Results: 1585 women received the intervention at a median (interquartile range) of 8.0 (5.0–15.0) days post-randomization and had a gestational age of 17.9 (15.4–20.6) weeks. Over 96% reported cooking exclusively with LPG at two follow-up visits during pregnancy. Less than 4% reported ever running out of LPG. Complete abandonment of traditional stove cooking was observed in over 67% of the intervention households. Of the intervention households, 31.4% removed their traditional stoves upon receipt of the intervention; among those who retained traditional stoves, the majority did not use them: traditional stove use was detected via SUMs on a median (interquartile range) of 0.0% (0.0%, 1.6%) of follow-up days (median follow-up = 134 days). Conclusions: The fidelity of the HAPIN intervention, as measured by stove installation, timely ongoing fuel deliveries, and behavioral reinforcement as needed, was high. Exclusive use of the intervention during pregnancy was also high.

High Fidelity: Delivery and use of an LPG stove intervention during pregnancy in the HAPIN trial

BACKGROUND AND AIM: Most previous cookstove trials have reported low intervention adoption and/or high continued traditional stove use, limiting interpretation of results. The Household Air Pollution Intervention Network (HAPIN) trial randomized 3195 pregnant women in resource-poor settings of four countries to a liquefied petroleum gas (LPG) stove and fuel intervention or to control. We assessed implementation fidelity (the extent to which the intervention was delivered as intended) and adherence (the extent to which it was adopted by participants) at the first trial endpoint: the end of the gestational period. METHODS: We tracked intervention fidelity through questionnaires at baseline ( 20 weeks gestation) and at two post-intervention visits (at 24-28 and 32-36 weeks of pregnancy), data collected by study staff (e.g. visual observations at fuel deliveries), and temperature-logging stove use monitors (SUMs) downloaded twice monthly. RESULTS:Over a median [Q1, Q3] follow-up period of 150 [131, 168] days per household, median time to repair for stoves requiring maintenance was 0 [0, 0] days (same day repair), and 87.2% of LPG refills were delivered within one week of request. 96.1% of intervention households reported LPG stove use at both follow-up visits. In the 70.0% of intervention households that retained traditional stoves after receiving their LPG stove, the median rate of traditional stove use was 0.0 [0.0, 1.6] days per 100 days of observation (using SUMs). In 70.6% of these households, traditional stoves were used on fewer than one in every 100 days of observation (Guatemala: 83.3%; India: 85.4%; Peru: 59.6%; Rwanda: 70.2%). CONCLUSIONS:The HAPIN intervention was largely delivered as intended, and participant adherence to the LPG stove intervention during pregnancy was high. Any observed differences in pollutant exposures or health outcomes between control and intervention groups are unlikely to be due to implementation failures during the gestational period. KEYWORDS: Air Pollution, Birth Outcomes, Community-engaged research, International Collaboration, Methodological study design, Particulate Matter

Monitoring of traditional stove use in the context of a clean fuel (liquefied petroleum gas, LPG) intervention trial in Guatemala, India, Peru, and Rwanda

Background: The Household Air Pollution Intervention Network (HAPIN) trial enrolled 3200 pregnant women who cooked with biomass fuel in Guatemala, India, Peru, and Rwanda; half were randomized to receive a liquefied petroleum gas (LPG) stove, approximately 18 months of free LPG, and behavioral messaging to promote LPG use. Although the intervention was designed to enable exclusive LPG use, investigators expected that some traditional stove use (TSU) would persist among intervention households. Methods: Thermocouple stove use monitors (SUMs, Geocene, Inc, Vallejo, USA) were installed on traditional stoves in intervention households. Data from SUMs were downloaded approximately every two weeks and TSU identified using a sensitive, deterministic algorithm. HAPIN fieldworkers visited households with detectable TSU events to administer a questionnaire on the reasons for TSU and reinforce exclusive LPG use. Results: Over 454,281 post-intervention household-days of monitoring among 1548 households (400 in Guatemala, 398 in India, 357 in Peru, and 393 in Rwanda), the rate of days with TSU per 100 household-days of observation was 0.83 (1.2 in Guatemala, 0.06 in India, 1.3 in Peru, and 0.8 in Rwanda). 95.1% of all households recorded one or no days with TSU on average per month (96.2% in Guatemala, 99.7% in India, 87.9% in Peru, and 95.9% in Rwanda). Primary reasons reported for TSU included: challenges with timely requests or receipt of LPG refills; resistance of other household members to LPG; uncertainty about how to clean, maintain, or check the LPG stove; and inability to cook large quantities of food with LPG. Conclusions: In the context of a free stove-and-fuel intervention combined with behavioral strategies to encourage exclusive LPG use, TSU events, measured by SUMs and direct observation, were infrequent at trial midpoint. The combination of SUMs data with household questionnaires provides a rich understanding of TSU persistence in the context of free LPG.

Effects of a randomized biomass cookstove intervention on glycated hemoglobin among women in Honduras

AIM: Using a stepped-wedge randomized controlled trial, we evaluated impacts of the wood-burning Justa cookstove (engineered combustion chamber, chimney) on glycated hemoglobin (HbA1c) among rural Honduran women. METHODS: We enrolled 230 cooks who were not pregnant, non-smoking, aged 24-59 years, and using a traditional stove. There were 6 study visits per participant, separated by 6 months. Participants were randomized to receive the Justa after 2 visits (Arm 1) or after 4 visits (Arm 2). We measured personal and kitchen 24-hour gravimetric fine particulate matter (PM2.5) and finger-stick HbA1c at each visit. We used linear mixed models adjusted for time and other covariates in intent-to-treat (assigned stove) and exposure-response (estimates per 1-unit higher log-transformed PM2.5) analyses. Sensitivity analyses included: limiting to the first 4 visits to approximate a parallel-trial design and, given large within-person variability in PM2.5 across visits, using geometric mean PM2.5 by assigned stove status for each participant as the exposure-of-interest. RESULTS: Among 227 women with 1,208 observations, Justa stove use reduced median (25th, 75th percentiles) personal PM2.5 concentrations (traditional: 82 µg/m3 [50, 142]; Justa: 43 µg/m3 [27, 73]). Participants had non-significantly reduced HbA1c when using Justa compared to traditional stoves (-0.06%, 95% CI: -0.16, 0.04). No associations were observed between personal and kitchen PM2.5 and HbA1c (0.01%, 95% CI: -0.03, 0.04; 0.02%, 95% CI: -0.01, 0.05; respectively). In sensitivity analyses limited to visits 1-4, a reduction in HbA1c was observed for Justa use compared to traditional stove use (-0.10%, 95% CI: -0.18, -0.01). Geometric mean personal and kitchen PM2.5 exposures were associated with HbA1c (0.03%, 95% CI: -0.03, 0.09; 0.04%, 95% CI: 0.001, 0.08, respectively). CONCLUSIONS: The Justa intervention reduced PM2.5 concentrations, but wide confidence intervals limit interpretations of HbA1c changes in primary analyses. Potentially relevant benefits were observed in sensitivity analyses and will be explored further.

Adoption and impact of improved cookstoves in Lambayeque, Peru, 2017.

Approximately three billion people in Asia, Africa, and the Americas cook with biomass, cleaner cooking technologies with the potential to reduce household air pollution exposure. It is necessary to assess the adoption and long-term use of these stoves, measure perceived benefits among users, and use this information to provide feedback to programs that are implementing new cooking technologies. The aim of this study is to determine the level of adoption and impact of improved biomass cookstoves in the rural area of Lambayeque, Peru, in 2017. A descriptive cross-sectional study was conducted. A total of 52 homes were surveyed in the districts of Pacora and Íllimo where improved biomass stoves were introduced between 2005 and 2013. A questionnaire for the assessment of adoption and impact indexes proposed by the Global Alliance for Clean Cookstoves was applied. The STROBE checklist was used. The mean number of years with the improved biomass cookstove was 9.1 (standard deviation: 2.9); 51.9% always used the improved stove, and 34.6% never used it due to destruction during the El Niño phenomenon in 2017. The median impact index was 5.62; 19.2% had a very good/good adoption. The median adoption index was 6.5; 25% had a very high/high impact. The use of the traditional or open fire biomass stove persisted in 61.5% of the houses. The adoption and impact of improved biomass cookstoves were acceptable, but traditional stove use persisted in more than half of the houses. Households used a mix of different stove technologies. Gas stoves were used more frequently for breakfast or dinner, while the traditional biomass stoves were used for larger lunchtime meals.

Women's experiences with mixed use of wood and gas cookstoves and fuels in rural Lambayeque, Peru

Introduction: Despite program efforts to encourage use of clean cookstoves and fuels to mitigate climate change, many communities continue to use wood-fueled open fires. Objectives: Describe experiences of participants with mixed use of cooking and fuel technologies (e.g. open fires and chimney stoves using wood and liquefied petroleum gas (LPG) stoves) in rural Lambayeque, Peru in 2018. Material and methods: Fifteen participants were interviewed using a qualitative exploratory research design. Data was collected through semi-structured interviews and analyzed using thematic content analysis. Results: Four categories emerged: decisions about acquiring cooking fuels are primarily based on cost; plastic trash is used to light wood-burning stoves; decisions to use gas over wood are based on quick food cooking time; and benefits and health problems are recognized, but mixed use of fuels persist. Conclusion: Use of both traditional wood cookstoves and plastic trash to ignite fires were used frequently because both are free or cheap. The environmental impact of cutting down trees isn't considered important, but interviewees did notice detriments to their wellbeing. Although gas stoves are used and benefits were mentioned, use of traditional stoves persists. We recommend that policy makers in Peru begin to address barriers to full adoption of new clean cooking technologies and consider governmental subsidies to meet families' spending priorities.

Everybody stacks: Lessons from household energy case studies to inform design principles for clean energy transitions

Stove stacking (concurrent use of multiple stoves and/or fuels) is a poorly quantified practice in regions with ongoing efforts to transition household energy to cleaner options. Using biomass-burning stoves alongside clean stoves undermines health and environmental goals. This review synthesizes stove stacking data gathered from eleven case studies of clean cooking programs in low- and middle-income country settings. Analyzed data are from ministry and program records, research studies, and informant interviews. Thematic analysis identifiedy key drivers of stove stacking behavior in each setting. Significant (28%–100%) stacking with traditional cooking methods was observed in all cases. Reasons for traditional fuel use included: costs of clean fuel; mismatches between cooking technologies and household needs; and unreliable fuel supply. National household surveys often focus on 'primary' cookstoves and miss stove stacking data. Thus more attention should be paid to discontinuation of traditional stove use, not solely adoption of cleaner stoves/fuels. Future energy policies and programs should acknowledge the realities of stacking and incorporate strategies at the design stage to transition away from polluting stoves/fuels. Seven principles for clean cooking program design and policy are presented, focused on a shift toward "cleaner stacking" that could yield household air pollution reductions approaching WHO targets.

Air Pollutant Exposure and Stove Use Assessment Methods for the Household Air Pollution Intervention Network (HAPIN) Trial.

Background:High quality personal exposure data is fundamental to understanding the health implications of household energy interventions, interpreting analyses across assigned study arms, and characterizing exposure–response relationships for household air pollution. This paper describes the exposure data collection for the Household Air Pollution Intervention Network (HAPIN), a multicountry randomized controlled trial of liquefied petroleum gas stoves and fuel among 3,200 households in India, Rwanda, Guatemala, and Peru.Objectives:The primary objectives of the exposure assessment are to estimate the exposure contrast achieved following a clean fuel intervention and to provide data for analyses of exposure–response relationships across a range of personal exposures.Methods:Exposure measurements are being conducted over the 3-y time frame of the field study. We are measuring fine particulate matter [PM in aerodynamic diameter ()] with the Enhanced Children’s MicroPEM™ (RTI International), carbon monoxide (CO) with the USB-EL-CO (Lascar Electronics), and black carbon with the OT21 transmissometer (Magee Scientific) in pregnant women, adult women, and children of age, primarily via multiple 24-h personal assessments (three, six, and three measurements, respectively) over the course of the 18-month follow-up period using lightweight monitors. For children we are using an indirect measurement approach, combining data from area monitors and locator devices worn by the child. For a subsample (up to 10%) of the study population, we are doubling the frequency of measurements in order to estimate the accuracy of subject-specific typical exposure estimates. In addition, we are conducting ambient air monitoring to help characterize potential contributions of exposure from background concentration. Stove use monitors (Geocene) are being used to assess compliance with the intervention, given that stove stacking (use of traditional stoves in addition to the intervention gas stove) may occur.Conclusions:The tools and approaches being used for HAPIN to estimate personal exposures build on previous efforts and take advantage of new technologies. In addition to providing key personal exposure data for this study, we hope the application and learnings from our exposure assessment will help inform future efforts to characterize exposure to household air pollution and for other contexts. https://doi.org/10.1289/EHP6422

Effects of a large-scale distribution of water filters and natural draft rocket-style cookstoves on diarrhea and acute respiratory infection: A cluster-randomized controlled trial in Western Province, Rwanda.

BackgroundUnsafe drinking water and household air pollution (HAP) are major causes of morbidity and mortality among children under 5 in low and middle-income countries. Household water filters and higher-efficiency biomass-burning cookstoves have been widely promoted to improve water quality and reduce fuel use, but there is limited evidence of their health effects when delivered programmatically at scale.Methods and findingsIn a large-scale program in Western Province, Rwanda, water filters and portable biomass-burning natural draft rocket-style cookstoves were distributed between September and December 2014 and promoted to over 101,000 households in the poorest economic quartile in 72 (of 96) randomly selected sectors in Western Province. To assess the effects of the intervention, between August and December, 2014, we enrolled 1,582 households that included a child under 4 years from 174 randomly selected village-sized clusters, half from intervention sectors and half from nonintervention sectors. At baseline, 76% of households relied primarily on an improved source for drinking water (piped, borehole, protected spring/well, or rainwater) and over 99% cooked primarily on traditional biomass-burning stoves. We conducted follow-up at 3 time-points between February 2015 and March 2016 to assess reported diarrhea and acute respiratory infections (ARIs) among children <5 years in the preceding 7 days (primary outcomes) and patterns of intervention use, drinking water quality, and air quality. The intervention reduced the prevalence of reported child diarrhea by 29% (prevalence ratio [PR] 0.71, 95% confidence interval [CI] 0.59–0.87, p = 0.001) and reported child ARI by 25% (PR 0.75, 95% CI 0.60–0.93, p = 0.009). Overall, more than 62% of households were observed to have water in their filters at follow-up, while 65% reported using the intervention stove every day, and 55% reported using it primarily outdoors. Use of both the intervention filter and intervention stove decreased throughout follow-up, while reported traditional stove use increased. The intervention reduced the prevalence of households with detectable fecal contamination in drinking water samples by 38% (PR 0.62, 95% CI 0.57–0.68, p < 0.0001) but had no significant impact on 48-hour personal exposure to log-transformed fine particulate matter (PM2.5) concentrations among cooks (β = −0.089, p = 0.486) or children (β = −0.228, p = 0.127). The main limitations of this trial include the unblinded nature of the intervention, limited PM2.5 exposure measurement, and a reliance on reported intervention use and reported health outcomes.ConclusionsOur findings indicate that the intervention improved household drinking water quality and reduced caregiver-reported diarrhea among children <5 years. It also reduced caregiver-reported ARI despite no evidence of improved air quality. Further research is necessary to ascertain longer-term intervention use and benefits and to explore the potential synergistic effects between diarrhea and ARI.Trial registrationClinical Trials.gov NCT02239250.

Adoption of improved biomass stoves and stove/fuel stacking in the REACCTING intervention study in Northern Ghana

In order to support transitions away from open-fire cooking and toward cleaner household energy systems, a better understanding of users’ technology adoption patterns and preferences is needed. This paper highlights key factors influencing use of two types of biomass-burning stoves provided through the REACCTING (Research on Emissions, Air quality, Climate, and Cooking Technology in Northern Ghana) randomized intervention study. We examine traditional and improved stove use over a two year follow up period, finding that the more basic rocket stove was used at a higher rate than the higher-tech gasifier stove. While stove use patterns varied by stove group, region, primary cook occupation, and socioeconomic status, use of traditional stoves remained high across most groups. Users perceived that improved stoves were less suitable for cooking a staple dish, Tuo Zaafi (TZ), and technical problems (e.g., battery failures with the gasifier stove) also limited the effectiveness of the intervention. Moving forward, household energy policies should prioritize a range of technologies that have potential to meet local needs while delivering meaningful health and/or environmental benefits, recognizing that stove and fuel “stacking” is likely to persist. A greater focus on markets and enabling environments is needed to support sustainable and scalable energy transitions.

Biogas Stoves Reduce Firewood Use, Household Air Pollution, and Hospital Visits in Odisha, India

Traditional cooking using biomass is associated with ill health, local environmental degradation, and regional climate change. Clean stoves (liquefied petroleum gas (LPG), biogas, and electric) are heralded as a solution, but few studies have demonstrated their environmental health benefits in field settings. We analyzed the impact of mainly biogas (as well as electric and LPG) stove use on social, environmental, and health outcomes in two districts in Odisha, India, where the Indian government has promoted household biogas. We established a cross-sectional observational cohort of 105 households that use either traditional mud stoves or improved cookstoves (ICS). Our multidisciplinary team conducted surveys, environmental air sampling, fuel weighing, and health measurements. We examined associations between traditional or improved stove use and primary outcomes, stratifying households by proximity to major industrial plants. ICS use was associated with 91% reduced use of firewood (p < 0.01), substantial time savings for primary cooks, a 72% reduction in PM2.5, a 78% reduction in PAH levels, and significant reductions in water-soluble organic carbon and nitrogen (p < 0.01) in household air samples. ICS use was associated with reduced time in the hospital with acute respiratory infection and reduced diastolic blood pressure but not with other health measurements. We find many significant gains from promoting rural biogas stoves in a context in which traditional stove use persists, although pollution levels in ICS households still remained above WHO guidelines.

Indoor and Outdoor Air Pollution- related Health Problem in Ethiopia: Review of Related Literature.

The health effects of air pollution are generally global problems, but they have, since recently become issues of particular concern for developing countries. This review assessed the situation of air pollution and related health effects in the context of Ethiopia. The materials reviewed in this publication are published scientific papers from online search engines, unpublished government reports and academic theses/dissertations. In addition, interview data obtained from authorities and experts involved in the management of air quality were analyzed, interpreted and reported in the article. Review of the few studies conducted in Ethiopia showed that average concentrations of PM2.5 reached as high as 280 µg/m3 for 24-hour measurements (range: 2,417-12,739 µg/m3). Indoor carbon monoxide (CO) levels were universally higher than regulatory limits for the United States and were found to be much higher among households using traditional stoves and solid biomass fuels. The use of traditional stoves and solid biomass fuels was reported in >95% of the households considered. High average levels of NO2 (97 ppb) were reported in a large longitudinal study. The ambient PM10 level was below the WHO guideline values in the majority of the samples. About 50% of the on-road CO samples taken from traffic roads in Addis Ababa were found to be less than the guideline values while the number of motor vehicles in Ethiopia is reported to be increasing by more than 9% per annum. There is a very limited air quality monitoring capacity in the country. The co-ordination between stakeholders in this regard is also inadequate. The limited evidence available on health effects of air pollution indicates that the prevalence of acute respiratory illness among children living in households using crude biomass fuels is significantly higher than the national average figures. The limited evidence reviewed and reported in this article indicates high levels of indoor air pollution and trends of worsening outdoor air pollution. This tentative conclusion carries with it the urgent need for more evidence-based research and capacity building in the areas of indoor and outdoor air pollution.

Assessment of cookstove stacking in Northern Ghana using surveys and stove use monitors

Biomass burning for home energy use is a major health and environmental concern. While transitioning to cleaner cooking technologies has the potential to generate significant health and environmental benefits, prior efforts to introduce improved cookstoves have encountered many hurdles. Here, we focus on the increased stove use hurdle; households tend to use improved stoves alongside their traditional stoves rather than replacing them entirely, a phenomenon called cookstove “stacking.” This work provides a systematic, multi-method assessment of households' cooking behaviors and cookstove stacking in the context of a 200-home randomized cookstove intervention study in Northern Ghana. Two stoves were selected for the intervention, a locally made rocket stove (Gyapa) and the Philips HD4012 LS gasifier stove. There were four intervention groups: a control group, a group given two Gyapa stoves, a group given two Philips stoves, and a group given one of each. Two stoves were distributed to each home in an attempt to induce more substitution away from traditional stoves. Adoption and usage patterns were quantified using temperature loggers at a subset of homes, as well as quarterly surveying in all households. We find that using multiple stoves each day is common practice within each intervention group, and that the two groups given at least one Gyapa had the largest reductions in traditional stove use relative to the control group, though use of traditional stoves remained high in all groups.

Understanding Consumer Preference and Willingness to Pay for Improved Cookstoves in Bangladesh

The USAID/WASHplus project conducted a comprehensive assessment to understand consumer needs and preferences as they relate to increasing the uptake and consistent, exclusive, and correct use of improved cookstoves (ICSs) in Bangladesh. The assessment included household ICS trials, fuel and stove use monitoring, and consumers’ perceived value of and willingness to pay for ICSs. Results showed that cooks appreciated and liked the ICS, but that no models met consumer needs sufficiently to replace traditional stoves. Initially, many preferred ICSs over traditional stoves, but this preference decreased over the 3-week trial period. Complaints and suggestions for improvement fell into two general categories: those that can be addressed through fairly simple modifications to the stove design, and those more appropriately addressed through point‐of‐purchase consumer education and follow-up from service agents or health outreach workers. Most households using the ICS realized fuel use reductions, although these were lower than expected, partly because of continued parallel traditional stove use. When given the option to purchase the stoves at market value, only one of 105 households did so; however, a separate assessment showed that 80% of participants (12 of 15 households) preferred to keep the stove rather than receive a cash buyout at market value. This indicates that users value the ICS when acquisition barriers are removed and highlights the need for better financing options.

Linking Household Energy Use with Indoor Air Quality

The WHO Indoor Air Quality Guidelines (AQGs) for Household Fuel Combustion used a model to derive the emission rates required to meet WHO intermediate targets and AQGs for PM2.5 and CO. The model used was a single zone model, a relatively simple construct which requires few assumptions and has been widely applied in air pollution and climate research. A probabilistic Monte Carlo approach was used to account for variability in physical characteristics and energy demands of households. Specifically, the model used input distributions of kitchen volumes, ventilation rates, daily usage times, and emissions capture efficiency (for chimney stoves) to produce output distributions of mean 24 hour PM2.5 and CO concentrations. The resulting output distributions were then compared with WHO targets and AQGs to estimate the percentage of homes that would meet or exceed these targets and AQGs. Emissions rates of the best-performance solid biomass technologies, when measured under controlled laboratory conditions, suggest that improvements in PM2.5 emission rates are needed for 60% of homes to meet the interim-1 annual AQG for PM2.5 (35?g m^-3^). Meeting the final PM2.5 AQG (10?g m^-3^) would require substantially greater emissions rate improvements for solid biomass stoves. Emission rates of solid biomass stoves measured during normal use in homes are greater than those measured in the laboratory, and these stoves typically do not fully displace traditional stove use, indicating a considerable challenge for meeting WHO targets and AQGs with these technologies. Use of clean-burning gas and liquid fuels such as LPG, natural gas, biogas, and ethanol, as well as electricity, however, represent technologies which can provide high levels of protection immediately.

Behavioral attitudes and preferences in cooking practices with traditional open-fire stoves in Peru, Nepal, and Kenya: implications for improved cookstove interventions.

Global efforts are underway to develop and promote improved cookstoves which may reduce the negative health and environmental effects of burning solid fuels on health and the environment. Behavioral studies have considered cookstove user practices, needs and preferences in the design and implementation of cookstove projects; however, these studies have not examined the implications of the traditional stove use and design across multiple resource-poor settings in the implementation and promotion of improved cookstove projects that utilize a single, standardized stove design. We conducted in-depth interviews and direct observations of meal preparation and traditional, open-fire stove use of 137 women aged 20–49 years in Kenya, Peru and Nepal prior in the four-month period preceding installation of an improved cookstove as part of a field intervention trial. Despite general similarities in cooking practices across sites, we identified locally distinct practices and norms regarding traditional stove use and desired stove improvements. Traditional stoves are designed to accommodate specific cooking styles, types of fuel, and available resources for maintenance and renovation. The tailored stoves allow users to cook and repair their stoves easily. Women in each setting expressed their desire for a new stove, but they articulated distinct specific alterations that would meet their needs and preferences. Improved cookstove designs need to consider the diversity of values and needs held by potential users, presenting a significant challenge in identifying a “one size fits all” improved cookstove design. Our data show that a single stove design for use with locally available biomass fuels will not meet the cooking demands and resources available across the three sites. Moreover, locally produced or adapted improved cookstoves may be needed to meet the cooking needs of diverse populations while addressing health and environmental concerns of traditional stoves.

Cooking practices, air quality, and the acceptability of advanced cookstoves in Haryana, India: an exploratory study to inform large-scale interventions

Background: In India, approximately 66% of households rely on dung or woody biomass as fuels for cooking. These fuels are burned under inefficient conditions, leading to household air pollution (HAP) and exposure to smoke containing toxic substances. Large-scale intervention efforts need to be informed by careful piloting to address multiple methodological and sociocultural issues. This exploratory study provides preliminary data for such an exercise from Palwal District, Haryana, India.Methods: Traditional cooking practices were assessed through semi-structured interviews in participating households. Philips and Oorja, two brands of commercially available advanced cookstoves with small blowers to improve combustion, were deployed in these households. Concentrations of particulate matter (PM) with a diameter <2.5 μm (PM2.5) and carbon monoxide (CO) related to traditional stove use were measured using real-time and integrated personal, microenvironmental samplers for optimizing protocols to evaluate exposure reduction. Qualitative data on acceptability of advanced stoves and objective measures of stove usage were also collected.Results: Twenty-eight of the thirty-two participating households had outdoor primary cooking spaces. Twenty households had liquefied petroleum gas (LPG) but preferred traditional stoves as the cost of LPG was higher and because meals cooked on traditional stoves were perceived to taste better. Kitchen area concentrations and kitchen personal concentrations assessed during cooking events were very high, with respective mean PM2.5 concentrations of 468 and 718 µg/m3. Twenty-four hour outdoor concentrations averaged 400 µg/m3. Twenty-four hour personal CO concentrations ranged between 0.82 and 5.27 ppm. The Philips stove was used more often and for more hours than the Oorja.Conclusions: The high PM and CO concentrations reinforce the need for interventions that reduce HAP exposure in the aforementioned community. Of the two stoves tested, participants expressed satisfaction with the Philips brand as it met the local criteria for usability. Further understanding of how the introduction of an advanced stove influences patterns of household energy use is needed. The preliminary data provided here would be useful for designing feasibility and/or pilot studies aimed at intervention efforts locally and nationally.