Gas Meter Research Articles

Projection segmentation-based image recognition technology for automatic reading of gas meter

In view of the shortcomings of the existing gas meter reading methods, this paper introduces an automatic reading method and calibration device based on the projection segmentation method, which uses the color difference between the character part and the rest part of the last code wheel of the gas meter counter to realize image recognition of the turned characters, and then calculates the cumulative volume indication of gas meter based on the number of turned characters. The pixel projection value scanned by the camera device at the horizontal centerline of the last code wheel changes alternately when the code wheel rotates. The proposed projection segmentation method does not require recognition of specific characters, simplifying the algorithm and making it suitable for most calibration devices. Experiments show that the accuracy rate of the proposed method is 100% even under low-light conditions, which is a great improvement compared with the traditional character recognition method. Additionally, the reading resolution of the proposed method is improved by 10 times compared with the existing photoelectric sampling method and template matching method, and the total calibration time can be reduced by 6.7%–58.7%, which significantly enhances the calibration efficiency.

Aeroacoustic analysis of flow induced resonance in a gas pipeline

Flow induced noise and vibration in the pipework of gas production platforms can lead to fatigue failures of attached small-bore pipes, and this can constrain the operating conditions of the platform. Typically such problems comprise a source of turbulence in the flow, an aeroacoustic feedback mechanism due to acoustic resonances inside the pipework, and mechanical resonances which amplify the resulting vibration. The problem described here occurred in the gas metering system of the platform, with the source located in the header which comprised a bifurcation into two metering lines and a number of sharp bends. Because of the cost of rectifying the problem an in-depth study was carried out to analyse the flow and induct acoustic conditions. The predictions will support recommendations for an efficient redesign of the entire system to control the problem at source. Various levels of CFD modelling (RANS and URANS) were carried out using the Openfoam code to predict the exact location and mechanism of the vortex shedding. The acoustic response of the complex ductwork was then modelled using the ACTRAN code to understand the feedback mechanism which led to resonance and high levels of response.

Enhanced Hydrolysis of Carbonyl Sulfide in Coking Oven Gas Utilizing an Efficient Ca-Ba-γ-Al2O3 Catalyst

China possesses a substantial capacity for coke production, resulting in the annual generation of over 100 billion standard cubic meters of the by-product coke oven gas. The comprehensive utilization of this gas has emerged as a matter of significant concern within the coking industry. The removal of carbonyl sulfide (COS) from coke oven gas is crucial for enhancing gas quality, mitigating equipment corrosion, minimizing environmental pollution, elevating the quality of recovered products, and fostering the production of high-quality steel. A novel Ca-Ba-γ-Al2O3 catalyst has been devised, employing γ-Al2O3 as the catalyst matrix and integrating calcium hydroxide (Ca(OH)2) alongside barium hydroxide octahydrate (Ba(OH)2·8H2O) as the alkaline activating components. The impact of various factors, including reaction temperature, humidity, and the number of activating components loaded, on the hydrolysis efficiency of COS has been meticulously investigated. Furthermore, the catalytic reaction mechanism has been elucidated utilizing advanced characterization techniques such as X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) analysis. The outcomes of this research reveal that, under optimal conditions of a reaction temperature of 55 °C and a humidity of 56%, the Ca-Ba-γ-Al2O3 catalyst achieves a remarkable COS hydrolysis efficiency of 95.22%.

Exploration of the Upgrading Path of China's Gas Meter Industry in the Digital Economy Era

Gas supply is a fundamental public good that affects millions of households. The online hot search event in April 2024 regarding the "fast running" of gas meters in multiple cities such as Chongqing and Chengdu indicates that there is still a long way to go in improving the quality and upgrading of the gas service industry and gas meter manufacturing industry. Based on the background of the digital economy era, this paper analyzes the role of gas meter manufacturers in the multilateral market of the smart gas management platform and the role of the gas meter industry value chain, explores the basic path and countermeasures for the upgrading of the gas meter industry, with a view to providing valuable reference for the digital transformation of the traditional gas meter industry in the industrial Internet era.

Assessment of impacts of air pollution on people living in Ezza North close to quarry operation sites in Ebonyi State, Nigeria

Quarrying activities have become lucrative work for low income people in low income countries most found in Africa. This study aimed assess the impacts of air pollution on people living in Ezza North close to quarry operation sites in Ebonyi State, Nigeria. A descriptive cross sectional study was used and pollution level was determined with the use of calibrated Handheld GPS, Amex multiple gas meter, Sound meter and interview of participants with a questionnaire on the health status. The collected data were entered into the Statistical Package for Social Sciences (SPSS) software (version 21). The one sample T-test was used to test the hypotheses at 95% confidence interval and 0.05 level of significance. The results showed that 31–40 years had 19(5.37%) males and 20(5.65%) females as highest quarrying workers. The concentration of carbon monoxide was highest at 193ppm, Sulphur dioxide at 568ppm, nitrogen dioxide at 1.9ppm, Suspended particulate Matter (SPM) at 1982ppm and sound level at 82.9dB. The concentrations of these pollutants were found to be significantly higher (P<0.05) than normal levels apart from sound level without significant impact at P = 0.285. The 93.3% of the participants reported blasting of rocks produced highest air pollution, 87.5% that reported crushing, conveying, sieving produce a lot of dust. Also, 80% of participants reported high level of noise came from machinery blasting rocks, processing and haulage trucks. In all, 35% reported they had fair health condition when asked about the health status since they started quarrying work. In conclusion, the concentrations of carbon monoxide, carbon dioxide, sulphur dioxide, particulate matter and nitrogen oxides were all higher than normal. It was observed air pollutants had association with respiratory system. Therefore, the air pollution at quarrying site can be mitigated through dust suppression techniques and treating quarry pit with water before discharging.

Identification and Ranking of Factors Affecting the Emission of CO Gas in Karkar Coal Mine

Karkar coal mine is one of the biggest mines in the country, where mining has been going on since 1938. During the mining period, the Karkar mine has witnessed unfortunate incidents caused by the release and explosion of gases, which have caused substantial financial and human losses. Carbon monoxide gas is one of the essential factors in the occurrence of accidents in the Karkar mine. This research includes literature reviews, field data collection using the CEM CO-181 model gas meter, and statistical calculations using Shannon entropy and Promethee methods. First, the concentration of CO gas was measured in ventilation tunnels, development, and excavation areas. Extraction workshops of the Karkar coal mine at different working times, and then 26 cases that may result in a reduction in accidents were used as effective criteria, and 9 cases were used as influential factors on CO emissions through the order and distribution of questionnaires and interviews with identified experts. The final weights of twenty-six effective criteria on the emission of CO gas were calculated based on the Shannon entropy method. As a result, the criterion of consumed oils with a final weight of 0.1790 was ranked first, and the criterion of lack of experience with a final weight of 0.1065 was ranked last. The influential factors have been ranked based on the amount of net flow and the parameter method. As a result, the factors of mining fire and coal dust explosion ranked first and last, respectively, with net flows of 0.55 and -0.84, and the rest of the factors are placed in different positions according to their net flow rate and have their effects on the emission of CO gas.

Life Cycle Assessment of Natural Gas Production in Java Sea-East Java Province, Indonesia

Energy products including natural gas play a very important role in the context of global economic, industrial, and infrastructure development. However, it is undeniable that the production process from raw material extraction to ready-to-use products has an impact on the environment. This study was conducted to evaluate the environmental impact of natural gas production in the Kepodang field, East Java Province, Indonesia. The next objective is to analyze the magnitude and significance of the impact or hotspot analysis. The characterization results for 4 main categories show: Global Warming Potential 70.02 kg CO₂ eq, Ozone Layer Depletion 1.11E-06 kg CFC-11 eq, Acidification Potential 0.65 mol H+ eq, Marine Eutrophication 0.30 kg N eq, and Freshwater Eutrophication 2.17E-03kg P eq. The results also show that throughout the life cycle of this product, the largest contributor to environmental impacts is in the downstream phase, especially the user gas metering unit process. This is due to the 200 km of pipelines for product transportation from the Central Processing Platform (CPP) to the user gate. Pipeline parameters (Ecoinvent database) refer to long-distance pipelines with high capacity. In addition, hotspots were also identified in the core phase: gas measurement and chromatography, gas turbine generators, and flare gas.

Optimizing turbine meter performance through geometrical parameter analysis: A simulation-based approach using TOPSIS

The number of blades and their angle in a turbine gas meter directly affect its performance and the amount of lift force, pressure drop and flow rate passing through the blades. In this research, the combination of software simulation and optimization method has been used as an effective research tool to investigate the effect of these geometric parameters on the amount of pressure drop, volume flow rate and lift force. First, the flow in a turbine gas meter is simulated using computational fluid dynamics. The set of governing equations including continuity, linear momentum and angular momentum have been solved by Fluent software. To simulate the turbulent flow, the standard k-ε model is used. In the next step, with the help of TOPSIS model, it has been optimized to check the effect of each of the parameters and determine their optimal values. The results of this research showed that by increasing the number of blades and increasing the blade angle, the lift force increases. Among the two parameters, the number of blades and the angle value, changing the number of blades has a significant effect. Reducing the number of blades and decreasing the blade angle can be effective strategies to minimize pressure drop. Also, the effect of changing the number of blades plays an important role in pressure drop. The pressure drop in the number of 20 blades is the highest and this's due to its large number of blades. In this article, 21 cases have been investigated with the help of TOPSIS and it can be seen that the angle of 30 ° with 12 blades is an optimal model. The ratio of lift force to drag force is observed at an angle of 30°, the number of 20 blades is the highest and its dimensionless value is 78.23. For an angle of 37.5°, the ratio of lift force to drag force for 20 blades has the highest value and its dimensionless value is 915.9. Also, for an angle of 45°, the ratio of lift force to drag force and the number of 20 blades has the highest value, and its dimensionless value is 1190.94.

Dynamic fractionation of methane carbon isotope during mass transport in coal with bidisperse pore structures: Experiments, numerical modeling, and applications

Gas-in-place (GIP) content and the in-situ free/adsorbed gas ratio are crucial factors for evaluating resource potential and optimizing production strategies of deep coalbed methane (CBM). While the prevailing notion that adsorbed gas predominates is widely accepted in shallow CBM, this idea has been contested in deep CBM. Various numerical models for calculating GIP content based on gas volume data from canister degassing experiments commonly suffer from low accuracy, strong multiplicity, and inability to evaluate critical parameters of free/adsorbed gas ratio. Isotope fractionation is an important tool for studying the occurrence state and transport mechanism of natural gas, and numerical modeling that considers both cumulative degassing content and carbon isotope data has proven effective in determining the GIP content and adsorbed gas ratio in shale. However, the applicability of the existing isotope fractionation models in deep CBM has yet to be demonstrated experimentally and theoretically. In this study, four coal samples from the Shanxi and Taiyuan formations in Ordos Basin were subjected to canister degassing, gas metering, and methane isotopic composition testing. The results revealed significant multi-stage carbon isotope fractionation characteristics throughout deep CBM degassing, reflecting the strong heterogeneous pore structure characteristics within the coal. Existing carbon isotope fractionation (CIF) models are unable to effectively characterize this complex phenomenon. Based on these findings, we innovatively developed a CIF model that considers bidisperse pore structures and multiple transport mechanisms. The model can better characterize the complex isotope fractionation behavior and reveal the mechanisms of carbon isotope transport in series structures of multi-scale pores. Using the model, we calculated the GIP content of four experimental samples from the Shanxi and Taiyuan formations on the southeastern edge of the Ordos Basin, ranging from 27.78 m3/t to 39.13 m3/t, with an average of 31.68 m3/t, and the in-suit free gas ratio ranges from 13.30 % to 32.89 %, with an average of 19.45 %. These research findings provided new insights for assessing the resource potential of deep CBM, screening sweet spots, and predicting gas well performance.

Quantifying the spatial variation of the energy performance gap for the existing housing stock in England and Wales

This paper evaluates the energy performance gap between Energy Performance Certificate predictions and annual gas meter reading measurements for the existing housing stock in England and Wales. Energy Performance Certificates predict energy using the SAP model, the UK regulatory tool for existing dwellings widely used in national and local housing energy policies. The results show an energy performance gap of between + 16.6 % and + 17.9 % at the national level. Of concern is that the performance gap is shown to vary greatly across different regions of England and Wales ( − 23.7 % to + 56.4 % for local authorities) and to vary with factors such as built form, construction age and predicted gas consumption. This suggests that there may be structural errors in the EPC/SAP approach resulting in certain spatial areas or dwelling types having more errors in their EPC predictions, impacting on future planning for housing stock retrofits.

The Strike-Slip Fault System and Its Influence on Hydrocarbon Accumulation in the Gudong Area of the Zhanhua Depression, Bohai Bay Basin

The Gudong area contains abundant petroleum resources. Previous studies have mainly focused on the extension structure in this area, with its strike-slip characteristics remaining poorly understood. In this study, the geometry of the strike-slip faults in the Gudong area was investigated using high-resolution 3D seismic reflection and drilling data, as were their associated releasing and restraining structures. Based on the profile’s flower structure and the plane’s horsetail splay pattern, the Gudong fault in the study area can be characterized as a dextral strike-slip. Three types of strike-slip fault-associated structures can be identified in the study area: (a) a restraining bend occurring in the right-stepping area of the S-shaped Gudong strike-slip fault, (b) a restraining bend identified in the left-stepping, overlapping zone of the Gudong and Kendong faults, and (c) a releasing bend seen in the extensional horsetail splay structure at the southern end of the Gudong fault. The restraining stress induced the formation of a fault-related open anticline, which led to a significant increase in fault sealing efficiency, thereby preserving an estimated 75.479231 million tons of oil and 15.28317145 billion cubic meters of gas. Conversely, releasing transtensional stress has compromised the effectiveness of the traps, preventing hydrocarbon retention. Consequently, oil and gas have migrated upward along the horsetail faults to the top of Cenozoic formations and have then dispersed.

On the use of perforated disk inserts in a round pipe to form a gas flow of the required structure in front of an ultrasonic flow meter

Unlike conventional gas meters, ultrasonic flow meters have such advantages as contactless operation, minimal pressure loss and high accuracy. When developing ultrasonic flow meters, like any other devices, assumptions and simplifications related to the theory of ultrasonic flow meters are used. When developing such devices, researchers do not always have the necessary space to deploy such structures. Therefore, the question arises of developing devices that can replace large sections of pipelines with various turns in the role of local resistances. The paper presents some studies conducted during the development of a perforated disk capable of forming a flow profile similar to the profile after a double bend. The presented results of a study of the influence of the perforated disk geometry on the gas dynamics and flow structure. The calculations were carried out using three-dimensional computer modeling. The analysis of the influence of the hole location, their sizes and the angles of inclination of the holes relative to the disk axis on the velocity distribution and the formation of the velocity profile downstream of the disk is the purpose of this study. Scalar and vector fields of velocities downstream of the perforated disk are obtained. Velocity profiles in sections behind the disk are constructed. A comparative analysis of different designs of perforated disks is carried out. The design principles of such flow formers are indicated. The geometric factors influencing the flow structure after the former are revealed. The revealed subtleties and described design principles made it possible to develop straighteners and flow formers based on perforated disks. The final samples of disks and the results of their operation are shown

Research on the flow characteristics of injecting hydrogen into natural gas pipelines and its impact on energy metering

Injecting hydrogen into natural gas pipelines for direct use by end users is an economical and effective method to realize long-distance transportation of hydrogen. However, the density of hydrogen is much lower than natural gas, and it tends to accumulate at the top of the pipeline, resulting in significant different flow characteristics of pure natural gas. Therefore, mixing hydrogen into natural gas pipelines will affect the accuracy of calorific value and flow rate measurement in the existing natural gas metering system. This article studies the flow characteristics of injecting hydrogen into natural gas using a T-shaped pipe and its impact on energy measurement through CFD numerical simulation. The results show that the energy metering equipment should be installed where the gas reaches a uniform mixture and the radial section velocity is centrally symmetrical. Injecting hydrogen with a lower position, and smaller main stream velocity will shorten the distance between the metering pipeline section and the mixing point, but a distance of at least 100 times the pipe diameter is still required. Thus, a mixing process combining a static mixer and flow straightener is proposed, which reduces this distance to within 40 times the pipe diameters.

A low-cost, open-source gas flow meter for laboratory-scale bioreactors

Biogas production measurement is a fundamental aspect of anaerobic digestion research. Lab-scale experiments usually require devices capable of measuring low flowrates and low relative pressures. Despite the existence of multiple commercially available alternatives for such demands, each with particular advantages and limitations, researchers have often resorted to in-house developed systems. This inclination is motivated by cost savings and the potential for of customization to suit specific research needs. Those systems, however, are seldom reproduced beyond laboratory walls due to overly complex designs, limited component availability or unpublished software. In this work, we developed a fully open-source lab-scale biogas flow meter equipped with datalogging capabilities. Our approach relied on inexpensive, widely available electronic modules. The flow meter was calibrated, tested and validated in batch biogas production experiments, alongside a comparative assessment with a proprietary device widely used in the field. The semi-continuous gas meter presented a resolution of 7.45 ± 0.13 mL and maintained a stable pulse volume (under 2 % relative standard deviation) for flowrates ranging from 60 mL h−1 to 1120 mL h−1. The device was not sensitive to the evaporative loss of up to 7 mL of packing liquid, demonstrating its applicability to long-term experiments. The developed system was shown to be robust and reliable and can be easily reproduced, revised and enhanced in laboratories everywhere.

Analysis of methods of natural gas technical loss determination and technical loss norms in gas supply network

In modern times, the role of energy resources is very large. One of the important energy resources is natural gas. The biggest advantage of using natural gas as a fuel is its high heat capacity and complete combustion without the formation of harmful substances. The process of natural gas distribution in the gas supply network is observed with gas loss. This is an objective, natural situation and creates a number of difficulties for natural gas enterprises. The article focuses on gas consumption in technological processes in the gas supply network, gas purges from pipelines during pipeline repair works, gas flushing out from the pipeline and determination of gas technological losses during the removal of air from the pipeline. Determination of gas losses caused by non-hermeticity of external gas pipelines and equipment, gas pressure regulation station (GPRS), cabinet-type gas control points (GCP), universal pressure regulator (UPR) and gas losses occurring during repairing of other technological equipment are discussed. Also, the determination of technical losses of natural gas at meters, sampling nodes, safety valves, gas distribution stations (GDS) (from gas losses during the management of shut-off valves, during purge of process instrumentation and automatics, when taking gas samples, during purges proses of safety valves, apparatus and pulse lines) is discussed. The article describes the principle of formation of technical losses in the gas supply network. Technical loss sources of natural gas in the process of gas supply, methods of calculating loss norms, the amount of small loss of which is determined separately for each specified loss source, are mentioned. Keywords: gas supply; natural gas; technical losses; pipeline; GPRS; GCP; UPR; gas meters; safety valves; gas distribution station.

Assessment of alternative fluid calibration to estimate traceable liquefied hydrogen flow measurement uncertainty

The usage of liquefied hydrogen (LH2) is growing fast as the EU aims to be climate-neutral by 2050. Therefore, reliable and consistent measurements of LH2 amounts (as determined by flow meters) will become increasingly important for custody transfers. Reliability and consistency of measurements is established from calibration. Due to the lack of facilities being able to calibrate flow meters directly with LH2 as calibration fluid, the question arises whether the measurement error of the calibration performed on a different fluid and different process conditions are representative for the errors when measuring LH2. An on-site calibration of two turbine meters measuring LH2 flow was performed. A Coriolis mass flow meter calibrated on water was used as a reference in conjunction with a dedicated flow meter model, which was validated by a directly SI-traceable calibration on liquefied natural gas. LH2 flow rates were within 1000 kg/h and 3000 kg/h, which are relevant to hydrogen transport by LH2 trailers. The analysis of the measurement data reveal errors on totalized mass ranging from 2.0 % to 2.9 % with a total calibration uncertainty of 1.3 % (k=2), where the main uncertainty source was identified as the on-site density estimate necessary to convert the volume flow measurements into mass flow measurements. The results indicate the need for reliable and accurate temperature measurements (the latter allowing for an accurate density estimate), so that volume based and mass based amount measurements can be compared with smaller uncertainties.

Evaluation of Recoverable Hydrocarbon Reserves and Area Selection Methods for In Situ Conversion of Shale

It is well known that the existing horizontal-well-drilling and hydraulic fracturing technology used to achieve large-scale, cost-effective production from immature to low–moderate-maturity continental shale in China, where the organic matter mainly exists in solid form, is fairly ineffective. To overcome the obstacles, in situ conversion technology seems feasible, while implementing it in the target layer along with estimating the amount of expected recoverable hydrocarbon in such shale formations seems difficult. This is because there are no guidelines for choosing the most appropriate method and selecting relevant key parameters for this purpose. Hence, based on thermal simulation experiments during the in situ conversion of crude oil from the Triassic Chang 73 Formation in the Ordos Basin and the Cretaceous Nenjiang Formation in the Songliao Basin, this deficiency in knowledge was addressed. First, relationships between the in situ-converted total organic carbon (TOC) content and the vitrinite reflectance (Ro) of the shales and between the residual oil volume and the hydrocarbon yield were established. Second, the yields of residual oil and in situ-converted hydrocarbon were measured, revealing their sensitivity to fluid pressure and crude oil density. In addition, a model was proposed to estimate the amount of in situ-converted hydrocarbon based on TOC, hydrocarbon generation potential, Ro, residual oil volume, fluid pressure, and crude oil density. Finally, a method was established to determine key parameters of the final hydrocarbon yield from immature to low–moderate-maturity organic material during in situ conversion in shales. Following the procedure outlined in this paper, the estimated recoverable in situ-converted oil in the shales of the Nenjiang Formation in the Songliao Basin was estimated to be approximately 292 × 108 tons, along with 18.5 × 1012 cubic meters of natural gas, in an area of approximately 8 × 104 square kilometers. Collectively, the method developed in this study is independent of the organic matter type and other geological and/or petrophysical properties of the formation and can be applied to other areas globally where there are no available in situ conversion thermal simulation experimental data.

Analysis of Internal Conditions and Energy Consumption during Winter in an Apartment Located in a Tenement Building in Poland

The residential sector of existing buildings has great potential in energy savings and the improvement of indoor conditions. The modernization of buildings is of particular concern to the policies of the European Union, local governments, and building users. The aim of this paper is to present an analysis of indoor parameters and energy consumption for heating for an apartment located in a pre-war tenement building before and after thermomodernization. The analysis was conducted for winter conditions and was based on measurements and simulations. Originally, the building had not undergone any thermomodernization actions since its reconstruction after WWII. Interior, exterior, and surface temperatures were recorded to describe the thermal conditions of the apartment, while gas meter readings were used to estimate energy consumption for heating purposes. WUFI Plus software (v.3.2.0.1) was used to estimate energy consumption and perform energy simulations for the apartment over an extended period of time. The best thermomodernization effect resulted from the replacement of windows and the inefficient heating system, avoiding surface condensation and reducing final energy consumption by more than 50%. The extended options resulted in energy savings higher than 70%. The presented analysis shows the importance of retrofit measures and proves that even a small improvement can bring significant benefits.

Addressing unaccounted-for-gas (UFG): Proactive techniques for optimal management and control

This study addresses the critical issue of Unaccounted-for-Gas (UFG) in Pakistan's gas sector, a significant challenge undermining operational efficiency and sustainability. With a comprehensive approach, the research introduces a tailored UFG Control strategy focused on "Network Visibility," "Network Rehabilitation," "Theft Control," and "Research & Development." These components aim to enhance the accuracy of gas metering and distribution, reduce losses through advanced technological interventions, and mitigate theft via robust monitoring mechanisms. By analyzing the period from 2013 to 2019, findings reveal the effectiveness of the proposed strategy in significantly improving operational efficiencies across the sector. The study also identifies key indicators for each strategy component, facilitating ongoing performance evaluation and strategic adjustments. This localized approach to UFG management not only offers a pathway to reduce gas losses but also underscores the importance of integrating modern technologies with existing infrastructure to address the sector's unique challenges. The research contributes valuable insights into the adaptation of international methodologies for the Pakistani context, highlighting the potential for regional customization in addressing UFG issues. This study endeavors to furnish policymakers and industry stakeholders with practical strategies aimed at improving the management and sustainability of Pakistan's natural gas sector.

Methane emissions from residential natural gas meter set assemblies

Residential natural gas meter set assemblies (MSAs) emit methane (CH4), but reported emissions factors vary. To test existing emissions factors, we quantified CH4 emissions from 37 residential MSAs in Calgary, Alberta, Canada. A notable difference with previous studies is the targeted measurement of regulator vents in this study, which were measured with a static chamber, while fugitives were measured with a modified hi-flow sampler. Emissions were dominated by pressure regulator vents (emissions factor = 1.18 g CH4/h/MSA), but 7 fugitives were found (emissions factor = 0.018 g CH4/h/MSA). Six regulator vents were emitting at notably higher rates (≥ 1.79 g CH4/h/MSA). The total empirical emissions factor was 1.20 g CH4/h/MSA (95 % CI, 1.03 to 1.37 g/h/MSA). This is ∼7 times higher than the emissions factor for residential MSAs used in the U.S. EPA's Greenhouse Gas Inventory, which may not include emissions from regulator vents. Upscaling to annual CH4 emissions in Calgary indicates 3234.6 t CH4/yr (95 % CI, 2776.4 t to 3692.9 t CH4/yr) could be emitted from MSAs. This is equivalent to 4.1 % (95 % CI, 3.5 % to 4.7 %) of total city-level CH4 emissions as estimated with satellite data. Results suggest residential MSA emissions may be under-estimated and further study isolating root causes of regulator vent emissions is required to guide mitigation and improve emissions modeling.