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SnO2 has been extensively used in the detection of various gases. As a gas sensing material, SnO2 has excellent physical-chemical properties, high reliability, and short adsorption-desorption time. The application of the traditional SnO2 gas sensor is limited due to its higher work-temperature, low gas response, and poor selectivity. Nanomaterials can significantly impact gas-sensitive properties due to the quantum size, surface, and small size effects of nanomaterials. By applying nanotechnology to the preparation of SnO2, the SnO2 nanomaterial-based sensors could show better performance, which greatly expands the application of SnO2 gas sensors. In this review, the preparation method of the SnO2 nanostructure, the types of gas detected, and the improvements of SnO2 gas-sensing performances via elemental modification are introduced as well as the future development of SnO2 is discussed.

Although energy densities of lithium-ion batteries (LIBs) continue to increase, safety problems such as fires and explosions have significantly hindered their large-scale applications. Conventional wisdom tells us the fire of LIBs largely originated from the flammable liquid carbonate solvents, and thus the research on additives with properties of suppressing “liquid-type fire” is the way to fabricate nonflammable batteries. However, the outcome has been proven to be inferior. Here, we carefully examined the evolution of battery fire under thermal abuse condition and found that the “jet fire” caused by flammable gases inside batteries is critical for the fire hazard, and the research effort should be redirected to search proper additives with “gaseous-type fire” suppressing properties. Unfortunately, conventional “gaseous-type fire suppressant” shows poor compatibility with battery electrolytes. Thus, we rationally designed a new kind of supramolecular electrolyte, where the molecules of “gaseous-type fire suppressant” and “SEI&CEI improver” are self-assembled together by intermolecular interactions. Due to this design, the supramolecular electrolyte produces improved cycling stability of Li metal anode and high voltage LiCoO2 cathode (up to 4.4 V). More importantly, it sharply decreases the self-extinguish time of carbonate electrolyte from ∼100 s/g to ∼0 s/g, which is unprecedented and can effectively suppress the “jet fire”, thus preventing the further combustion of commercial pouch cell during thermal runaway. Our work is providing the criteria required to overcome this challenge via supramolecular engineering of the electrolyte, which provides a new way to tune electrolyte functions and may bring numerous new possibilities.

In Press, Journal Pre-proof The hunt for new refrigerant blends has been concentrated to locate A1 refrigerants. However, the investigation for A2 or A2L blends to replace hydrocarbons (A3) has not attracted attention yet, although these mixtures will allow to increase the maximum charge of refrigeration systems from 500 g to 1200 g. This paper extends Linteris’ et al. work to define, for first time, the frontier between A3 and A2 ASHRAE safety classifications with an approach that can avoid large experimental campaigns. Then, using the methodology, it determines the composition limits of possible A2 binary blends with hydrocarbons that have a GWP below 150. Only mixtures of hydrocarbons with A2 or A2L components meet the criteria, and the composition of the least flammable fluid is predominant. Proposed hypothesis, developed theoretically, should be completed in the future with experimentation, to quantify the energy performance of found blends. Funding for open access charge: CRUE-Universitat Jaume I

Hydrofluorocarbons(HFCs) are potent greenhouse gases in refrigeration systems, and their contribution will accelerate climate change. In the context of global warming, low global warming refrigerants have to be reconsidered, these refrigerants are commonly flammable, so systems that use them can pose a risk. Thus, an analysis of potential pipe leaks in refrigeration systems is urgently needed. In existing research on refrigerant leak, most studies have examined holes as leak points. However, the true morphology of leak points is commonly long and extremely narrow. Therefore, a round-pipe microcrack leak model with crack opening displacement (COD) ranging from 10–50 µm were built to perform a simulation and experiment. The Fluent (v.20, ANSYS Inc.) software performed computational fluid dynamics analysis. The R290, R32, and R1234yf refrigerants were simulated, and the orifice flow equation was introduced to calculate leakage from the microcrack. An axial and circumferential microcrack model was constructed, and the experiment validated the simulation with largest relative error of 2.9%. The simulation results indicated that for side flow through the microcrack, using the conventional discharge coefficient ( C d ) in the orifice equation may be unsuitable. Accordingly, based on the simulation results, empirical equations for predicting the C d of axial microcrack when R290, R32, and R1234yf are leaking are obtained. Additionally, the effect of length-to-diameter ratio and orifice-to-pipe-diameter ratio on C d are also discussed. Compared with existing studies, a smaller infinity discharge coefficient value ( C d ∞ ) was observed when COD 30 μ m .

Flexible polyurethane foam (FPUF) is the most used polyurethane, but the highly flammable characteristic limits its widespread usage. In this work, ZIF-8@Ti3C2Txwas synthesized to reduce the heat and toxic gases of FPUF. Flame-retardant FPUF was characterized by cone calorimeter (Cone), thermogravimetric analysis/fourier-transform infrared spectroscopy (TG-FTIR), tensileand compression tests. Compared with pure FPUF, these results showed that the peak of heat release rate (PHRR), total heat release (THR), CO and HCN of FPUF6 decreased by 46%, 69%, 27% and 43.5%, respectively. Moreover, the tensile and compression strength of FPUF6 demonstrated a 52% and 130% increment, respectively. The superior dual metal catalytical charring-forming effect and physical barrier effect of ZIF-8@Ti3C2Tx were achieved. In summary, a simple and reliable strategy for preparing flame-retardant FPUF with reinforced mechanical and fire safety properties was provided.

Due to massive flammable chemical materials and dense layout, domino accident chain always occurs in major accidents of atmospheric storage tank farm. In this paper, 136 domino effect accidents of atmospheric tanks are analyzed to achieve relative probability by ETA method. Based on accident probability, an analysis model is proposed to define the most likely accident chain and the key tank in the atmospheric tank farm. To get the real accident scenario, the method adopts the heat radiation model of pool fire under the fire extinguishing conditions. Combined with the dynamic Bayesian network, the escalation model of accident chain is established to figure out the dynamic probability of the tank under the condition of fire extinguishing. Finally, an example is used to verify the feasibility of the method. It is of great theoretical significance and application value for the treatment of domino accident in atmospheric tank farm.

Cotton fibers mainly consist of cellulose biological macromolecule, and its exceedingly flammable nature has severely restricted its application in the fields requiring flame retardancy. To endow cotton fabric with excellent flame retardancy and superior durability, a high-efficiency durable flame retardant (THPO-P) with ammonium phosphate ester and phosphine oxide groups was synthesized and chemically bonded to cotton fabric through padding-baking method. THPO-P showed high flame-retardant efficiency, and the add-on of 5.9% was sufficient to prepare cotton fabric with self-extinguished feature. With the add-on of 19.9%, treated fabric possessed excellent fire safety and durability. The total heat release and peak heat release rate values reduced by 77.1% and 91.8% in contrast to pristine fabric, respectively. Its LOI value still reached up to 33.4% even after 50 laundering cycles, which was far beyond the flame-retardant standard. THPO-P played flame-retardant role by restraining the release of flammable volatiles, liberating nonflammable gases and promoting the char formation during combustion. The flame-retardant treatment deteriorated the tensile strength, whiteness and softness of cotton fabric.

Lithium ion batteries (LIBs) are widely used as important energy sources for mobile phones, electric vehicles, and drones. Experts have attempted to replace liquid electrolytes with solid electrolytes that have wider electrochemical window and higher stability due to the potential safety risks, such as electrolyte leakage, flammable solvents, poor thermal stability, and many side reactions caused by liquid electrolytes. However, finding suitable alternative materials using traditional approaches is very difficult due to the incredibly high cost in searching. Machine learning (ML)-based methods are currently introduced and used for material prediction. However, learning tools designed for domain experts to conduct intuitive performance comparison and analysis of ML models are rare. In this case, we propose an interactive visualization system for experts to select suitable ML models and understand and explore the predication results comprehensively. Our system uses a multifaceted visualization scheme designed to support analysis from various perspectives, such as feature distribution, data similarity, model performance, and result presentation. Case studies with actual lab experiments have been conducted by the experts, and the final results confirmed the effectiveness and helpfulness of our system.

The gas booster station of a steel works has experienced excessive bearing failures since commissioning over two decades ago. This station was designed with redundancy, allowing for automatic switch-over between two gas booster fans. Bearing failures were observed, on average once every 15.7 days, with instances where both fans experienced simultaneous downtime. Booster failures resulted in regular station downtime, preventing Coke Oven Gas (COG) transport to an end user. This flammable by-product is used as a heat source and all unutilized volumes are flared, resulting in energy wastages. Furthermore, the absence of COG increases Natural Gas (NG) usage, procured at a cost. Traditional root cause analysis techniques failed to identify the cause of these excessive bearing failures. However, multiple in-depth data analysis studies resulted in a thermodynamic investigation, exposing liquid and solid particles within the COG to be responsible for the failures. This allowed for the design of an in-line particle collector, eliminating excessive failures. Following the particle collector installation, only two strategic bearing changes took place over the next 41 weeks, with reduced bearing vibration levels compared to before. The station experienced no failure downtime during this period, resulting in reduced COG flaring and thus improved energy utilization.

Energy sustainable development has stimulated the pursuit of an eco-friendly energy storage system. Carbon peak and neutrality targets oriented energy storage development will guide the way of further studies on batteries system. However, conventional batteries system (lead-acid batteries, lithium-ion batteries) based on ungreen transition metal oxide, flammable electrolytes or hazardous metals cannot keep pace with the development of society sooner or later. Thus, vast explorations on the advanced rechargeable battery systems were conducted. Compared with other battery systems, zinc ion battery systems with inherent safety, low cost were widely investigated. Especially, the zinc organic batteries based on the eco-efficiency organic cathodes were promising alternative advanced batteries for future energy storage systems. Therefore, various organics and different electrochemistry mechanisms were explored in the zinc batteries system. Herein, a timely review on elaborate analysis about functional groups, fundamentals, progress accompanied by the discussion on the four core issues: voltage, capacity, rate performance, cycle life was presented. Specifically, aiming at these issues, three levels of solution strategies: materials design concepts, morphology structure optimization and electrolyte environment were summarized and proposed for the development and innovation of zinc organic batteries.

PurposeThe purpose of this paper is to analyze the reliability of the quantitative risk model used for planning inspection and maintenance activities. The objective is to critically discuss the factors that contribute to the probability and consequence of failure calculations.Design/methodology/approachThe case study conducted using one of the most widely deployed risk models in the oil and gas industry where a full assessment was performed on an offshore gas producing platform.FindingsThe generic failure frequencies used as the basis for calculating the probability of failure are set at a value representative of the refining and petrochemical industry's failure data. This failure database does not cover offshore. The critical discussion indicated the lack of basis of the coefficient of variances, prior probabilities and conditional probabilities. Moreover, the risk model does not address the distribution of thickness measurements, corrosion rates and inspection effectiveness, whereas only overall deterministic values are used; this requires judgment to determine these values. Probabilities of ignition, probabilities of delayed ignition and other probabilities in Level 1 event tree are found selected based on expert judgment for each of the reference fluids and release types (i.e. continuous or instantaneous). These probabilities are constant and independent of the release rate or mass and lack of constructed model. Defining the release type is critical in the consequence of the failure methodology, whereas the calculated consequences differ greatly depending on the type of release, i.e. continuous or instantaneous. The assessment results show that both criteria of defining the type of release, i.e. continuous or instantaneous, do not affect the calculations of flammable consequences when the auto-ignition likely is zero at the storage temperature. While, the difference in the resulted toxic consequence was more than 31 times between the two criteria of defining the type of release.Research limitations/implicationsThere is a need to revamp this quantitative risk model to minimize the subjectivity in the risk calculation and to address the unique design features of offshore platforms.Originality/valueThis case study critically discuss the risk model being widely applied in the O&G industry and demonstrates to the end-users the subjectivity in the risk results. Hence, be vigilant when establishing the risk tolerance/target for the purpose of inspection and maintenance planning.

This paper presents a review of current trends in the development of manufacturing technologies of sensors of pre-explosive concentrations of flammable gases and vapors of flammable liquids. Various types of gas sensors are discussed, including catalytic, semiconductor, and optical sensor types, and the principles of their operation. The advantages and disadvantages of each type of gas sensor are highlighted. New and traditional technologies for manufacturing sensitive elements that improve sensor parameters such as processability, miniaturization and reduce energy consumption are discussed. In conclusion, this article suggests future trends and prospects for development and research to improve the sensitivity and selectivity of sensors.

Due to the recent coronavirus pandemic, there is a steep rise in the use of alcohol-based hand sanitizers (ABHSs) over the past few months. For them to be effective against microorganisms, the minimum recommended concentration of alcohol is 60%. This high alcohol content makes the sanitizers easily flammable. Although, they are extremely convenient to use, they can also prove to be a hazard if used in an improper manner. Guidelines have been published for safe manufacturing and distribution of these sanitizers. There are recommendations for storage and use, which should be adhered to in a strict manner. Their use by children should always be supervised. We report four cases of burn injuries caused by injudicious use of alcohol-based sanitizers. The flammable nature of ABHSs can also be exploited as witnessed in one of our cases. With this report, we wish to emphasize that judicious and correct use of these seemingly benign products is essential.

Knowledge of sizes of leak holes arising in refrigeration, air conditioning and heat pump systems is critical for safe application of flammable refrigerants, especially hydrocarbons such as R290. Data for leak hole sizes is currently lacking so safety standards have used a range of assumed leak rates that maybe unreasonable and lead to severe restrictions on charge limits and/or high costs for addressing potential ignition sources. Over 1000 leak holes have been measured from various systems. The leak hole areas were found to be clustered around very small values with more than 90% below 0.10 mm2 and 98.8% smaller than 1.0 mm2, irrespective of type, age and size of the system. The largest leak hole size that should be considered for safe design of systems is around 0.5 mm2, or about 70 g min−1 of R290 vapour or adjusted according to the system operating conditions or type of refrigerant.

Temperature sensing enables flammable materials to respond intelligently at high temperature, which is conducive to further improving their fire safety. However, it is still challenging to develop a smart nanocoating with sensitive temperature-sensing and efficient flame retardancy. Inspired by human skin, a thermoelectric flame retardant (TE-FR) nanocoating was fabricated by combining a dermis-mimicking thermoelectric (TE) layer and an epidermis-mimicking flame retardant (FR) layer. The TE-FR nanocoating exhibited accurate temperature sensing at 100–300 ℃ and repeatable fire-warning capability. When being burned, the fire-warning response time of the TE-FR nanocoating was only 2.0 s, and it retriggered the fire-warning device within 2.8 s when it was reburned. Meanwhile, the TE-FR nanocoating exhibited outstanding flame retardancy. The coated polypropylene self-extinguished in the horizontal and vertical burning tests. Besides, its peak heat release rate, total heat release, and peak smoke production rate were significantly reduced. This work proposed an ingenious strategy to fabricate smart nanocoating for temperature sensing and fire safety, which revealed an enticing prospect in the fields of fire protection, electronic skin, and temperature monitor.

Both military and civilian vehicles are prone to fire, with severe potential consequences in terms of material and life losses. Vehicles generally contain highly combustible and flammable materials, such as gasoline, lubricants, oil, electronic devices, rubber, plastics, and so on. At the same time, fire ignition sources are present in vehicles in electronic devices, friction, heat, etc. Fire ignition can also be caused by external sources, especially in military applications (aggression on the vehicle). Thus, appropriate measures and fire-fighting systems should be implemented to mitigate the risk of fire in military and civilian vehicles to ensure passenger safety and preserve the vehicles' mobility. Halon was previously commonly used as a fire-fighting agent in military and civilian vehicles but is currently phased out due to environmental issues. In this context, this paper aims to review the research advances and progress over the last 50 years in fire-fighting systems and agents employed in both civilian and military vehicles for land, sea, and air applications.

Constructing a fence for potential liquid hydrogen leakage is a common protective measure to prevent the unrestricted spread, and critically evaluating the effects of a fence is essential for the safe use of hydrogen energy. Based on NASA's large-scale experiment of liquid hydrogen release, a 3D numerical model considering the existence of fence is proposed to study the dynamic spread behaviors of hydrogen flammable cloud and liquid hydrogen pool. The results show that the liquid hydrogen pool keeps a downwind radius of about 1.75 m most of the time during the release, and the hydrogen flammable cloud has a limit spread distance. Three cases are set to comparatively evaluate the effect of the fence, which are full fence, downwind half fence and no fence. Under the three cases, liquid hydrogen pools all evaporate completely within 5 s. Full fence scenario has the modest spread scale of hydrogen flammable cloud in the atmosphere but the longest duration for 86 s, and the upwind fence causes an easily overlooked hazardous region due to the vortex here, thus constructing a full fence is not an ideal strategy when the spread direction is constant. Just constructing a downwind half fence leads to the greatest spread distance of the flammable hydrogen cloud, which are 33.6 m and 68 m in vertical and downwind directions. No fence case corresponds to the smallest diffusion scale of flammable hydrogen cloud in atmosphere but the longest near-ground spread distance for 43.35 m. Four stages can be divided to summarize the entire life period of the flammable cloud for the cases with and without a fence, while three stages for the case with a downwind half fence.

Alkaline electrolysis (AEL) is the most mature electrolysis technology and is widely used in large-scale power-to-gas scenarios. However, the loading range of AEL system is restricted by the minimum load, 10%–40% in general, which prevents system operation during low-load periods. This minimum load is caused by the flammable mixture formed by the impurity crossover and is related to operation conditions such as current and pressure. In this paper, we propose a novel pressure control strategy to extend the loading range of an AEL system by reducing the system pressure at low-load periods while also maximizing the system efficiency. A dynamic impurity accumulation model is established illustrating the flexibility limitation mechanism of the AEL system. Two pressure controllers are designed based on the steady-state and dynamic impurity accumulation model, including an operation curve tracking controller (OCT) and a model predictive controller (MPC). In the case study, both controllers achieve satisfying results under the peak shaving scenario, with an extension of the AEL system's minimum load from 27.5% by the traditional constant pressure controller to 10.5% by the OCT controller and 10% by the MPC controller. This pressure control strategy reduces the electricity abandonment and improves the system economy significantly.

The transportation industry demands the flammability control in the safe transportation of any liquid mixtures. Here the flashpoint of a flammable solvent is controlled by adding an evaporative diluent into the mixture. The flashpoint of this binary mixture is predictable with the help of Method of Flammable Resistance. Here methanol and heptane were chosen as typical fuels to be tested while R141b and R1233zd were added to control the flashpoint. Experimental results show that the binary mixture demonstrated the predicted behavior with the help of a new modeling scheme for mixing and the activity models for non-ideal evaporation. This methodology has the potential for predicting the flashpoint of any combinations of solvents, though some kind of synergistic behavior may appear when small fraction of a diluent is involved.

A significant number of emergencies that occur in the chemical, processing and transport industries begin with an accidental spill and ignition of a flammable liquid. In this case, the spread of fire to neighboring objects is of particular danger. When developing fire protection measures in areas where flammable liquids are stored, as a rule, heat transfer from a fire only by radiation is taken into account. But in some cases, the convection component of the heat flow can make a significant contribution to the overall heat transfer. Ignoring it can lead to an erroneous assessment of the safety of an industrial facility. In the paper, a model of the distribution of velocity and temperature in the upward flow, rising above the spill of a burning liquid, is constructed. The model is based on the system of Navier-Stokes equations, which, by means of simplifications, is reduced to a non-linear second-order differential equation of the parabolic type. The properties of the combustion site determine the boundary conditions of the first kind. In this case, the spill of a flammable liquid can have any shape. The presence of wind is taken into account by introducing a stable horizontal component of the flow velocity. For the numerical solution of the equation, the method of completed differences is used. The dependence of the kinematic viscosity on the flow temperature is taken into account. An empirical formula is used as the relationship between temperature and speed. It is shown that the presence of wind leads to an inclination of the ascending flow. The angle of inclination is not constant and increases with distance from the combustion source due to a decrease in speed and cooling of the flow. An estimate of the coefficient of convection heat transfer convection of the tank wall with ascending flows over the combustion source is constructed. It is shown that the coefficient of convection heat transfer increases with increasing wind speed

In the CO2 transcritical power cycle, conventional cooling water can hardly condense subcritical CO2 because its critical temperature is as low as 30.98°C. In order to avoid this condensing problem, CO2-based mixtures have been proposed as working fluids for transcritical power cycle. They can raise the critical temperature by mixing a little C3H8 as the secondary component to CO2. However, the flammability of the mixture may limit its application. This article investigated laminar flame speed of C3H8/CO2 which represents the mixture’s combustion characteristic by a so-called heat flux method and studied the inhibition mechanism of CO2 on the combustion based on the Premixed Laminar Flame-Speed Calculation reactor of Chemkin-Pro. The experimental results showed that the laminar flame speed shows a peak value with changing the equivalence ratio and accelerates with raising the mole fraction of the organic gas. Additionally, a slight upwards trend was observed for the corresponding equivalence ratio of the peaks. The flammable range for the equivalence ratio extended with the mole fraction of C3H8 increasing. With the mole fraction of C3H8 of 0.15, the maximum laminar flame speed was 12.8 cm/s, 31.7% of that of the pure C3H8. The flammable range was from 0.41 to 1.33, decreasing by 23.3% compared with that of C3H8. A flammable critical mixing ratio was also found as 0.08/0.92 for C3H8/CO2 at the normal condition. By simulating, it was found that the most key free radical and elementary reaction which determine the inhibition of CO2 on the combustion are OH and H+O2=O+OH, respectively.

The leakage of toluene from damaged tanks can threaten both workers and the environment; ergo, the effects and consequences of toluene leaks can be modeled and quantified to aid in emergency planning and response management. This study modeled the effects and consequences on various scenarios of toluene release via the ALOHA and PHAST programs: evaporation puddle formation, dispersion of toxic and flammable vapor clouds, the distribution of lethal concentrations, and the probability of death from a toluene leak from a height of 6 m of the tank wall. The outputs of the two modeling programs were analyzed and compared. The results showed that the maximum threat zone distances associated with high hazards of toxicity, flammability, and thermal radiation of toluene were respectively 736, 132, and 52 m in ALOHA and 1626, no result, and 239 m for PHAST from the accident point in the downwind. The highest probability of death was 92%, which occurred at a distance of 1 m in the cold seasons. The output values for the PHAST program were higher than those for ALOHA. The results also showed that the survival zone in which the probability of death was low could be determined from a distance of 51 m onwards. Although the assessment of the results indicated no matching between the results obtained by ALOHA and PHAST, the program outputs could still help decision-makers in emergency response planning and the allocation of medical and support services during emergencies.

Foamed concrete is an attractive material for structural use and insulation of buildings, which can replace flammable organic insulating materials on the market. This study investigated the compres...

Industrial and population expansion in the last few decades has been a critical contributor to water quality degradation. Some of the gases emanating from water treatment plants are toxic and flammable, which need to be identified, such as hydrogen sulphide, carbon dioxide, methane, and carbon monoxide. Water quality monitoring systems must be developed to meet legal, environmental, and social requirements. Monitoring water quality is difficult due to the variability, nature, and low concentrations of contaminants that need to be detected. The gas emanating from these treatment processes plays an essential role in water treatment, monitoring, and control. Gas sensors can be used as a safety device in the water purification process. The gas sensors receive input signals in chemical, physical, and biological stimulus and convert them into electrical signals. The gas sensors can be installed in different wastewater treatment processes. In this review, we present state-of-the-art progresses, landmark developments, and technological achievements that led to the development of gas sensors for evaluating water quality. The role of gas sensors in water quality maintenance and monitoring is discussed, and different analytes and their detection technologies and sensing materials outlining their advantages and disadvantages have been summarized. Finally, a summary and outlook for future directions of gas sensors in water quality monitoring and maintenance are provided.

With the improvement of lithium-ion battery (LIB) technology, safety is becoming increasingly urgent topic for battery electric vehicles (BEVs). Short circuits, overcharging, high temperatures and overheating can cause thermal runaway reactions and the release of the flammable electrolyte which makes fire suppression very difficult. This study focuses on the mechanism of thermal runaway and fire suppression applications of LIBs. In order to understand this, 10 experiments were carried out. The experiments were divided into as Exp. A and Exp. B. A manual water suppression system was used in Exp. A and an automatic boron-based suppression system (AUT-BOR) was used in Exp. B. LIBs were heated in a controlled manner with a heat source and the effects of thermal runaway and fire suppression were observed. In Exp. A, a large amount of water was required to extinguish the LIB fires. The holes and slits which formed in the LIB after a fire were useful for injecting water. A projectile effect of cylindrical cells was observed in Exp. A. The Exp. B results showed that AUT-BOR mitigates risks effectively and safely. Also, AUT-BOR provides an early fire warning system and spot cooling to prevent thermal runaway reactions while localizing and suppressing the fire. In Exp. B, fire detection and suppression occurred without any explosion.

Fuel cell (FC) is simply a device that directly converts the chemical energy of fuel into electrical energy through electrochemical oxidation. Hence, FC inherently exhibits a low-temperature and high-energy conversion efficiency. Direct alcohol fuel cells (DAFCs) overcome the storage, handling, and safety challenges typically associated with gaseous fuels such as hydrogen. Most of the research and development work in DAFC is focusing on maximizing its performance by varying fuel concentration, operating conditions, and electrocatalysts used. However, less attention is being given to the health and safety aspects associated with these fuels and operating conditions. Most of these fuels are known to be highly flammable, toxic, and become even more hazardous at elevated temperatures. The present work performs a systematic assessment of the safety and health aspects of the widely used fuels for DAFCs, namely methanol, ethanol, ethylene glycol, and glycerol. The safety assessment is considering the flammability characteristics, along with other safe operation aspects. While the health assessment considers the toxicity of fuel and its reaction byproducts to human and aquatic life. The evaluation has provided an envelope of conditions at which the FC operation would be considered “safer” by applying basic principles of inherent safety, i.e., minimizing, substituting, moderating, and simplifying.

Introduction. The relevance of the topic, addressed in the article, is backed by the fact that modern heating systems, such as the underfloor heating, remain potential sources of fire, despite the improvement in their designs. The purpose of the study is to identify the causes of fires that occur in the process of operation of modern heating systems “Underfloor Heating”; to analyze and generalize the conclusions made by the fire safety experts in respect of the heating systems analyzed in the article.Materials and methods. To assess the flammability of the infrared film underfloor heating, an experiment was conducted by the experts: the process of underfloor heating was simulated under normal environmental conditions at room temperature.Results and discussion. The experiment has shown that the floor covering, made of the material capable of accumulating heat, is the most dangerous one, although its small area prevents its disconnection from the thermal sensor. When dismantling the construction, the co-authors found out that the foil insulator had been melting in the area of maximal temperatures. Over the course of seven hours of operation, the temperature exceeded 120 ºC, and after that the odor of products of thermal decomposition of a synthetic product appeared.Conclusions. Despite all the features of advanced underfloor heating systems, their automated operation and transformation, they remain potentially flammable. Modern underfloor heating systems can take fire both as a result of violation of the fire precautions in case of non-compliance with the requirements for the operation of heating devices, and as a result of overheated film heaters located under the floor covering.

Graphite, a robust host for reversible lithium storage, enabled the first commercially viable lithium-ion batteries. However, the thermal degradation pathway and the safety hazards of lithiated graphite remain elusive. Here, solid-electrolyte interphase (SEI) decomposition, lithium leaching, and gas release of the lithiated graphite anode during heating were examined by in situ synchrotron X-ray techniques and in situ mass spectroscopy. The source of flammable gas such as H2 was identified and quantitively analyzed. Also, the existence of highly reactive residual lithium on the graphite surface was identified at high temperatures. Our results emphasized the critical role of the SEI in anode thermal stability and uncovered the potential safety hazards of the flammable gases and leached lithium. The anode thermal degradation mechanism revealed in the present work will stimulate more efforts in the rational design of anodes to enable safe energy storage., The role of the lithiated graphite anode in battery thermal runaway failure remains under intense investigation. In this work, with multiple in situ synchrotron X-ray characterizations, the phase evolution, gas release, and lithium leaching of lithiated graphite anode are illustrated in detail.

Following the entry into force of the Regulation (EU) No 517/2014 of the European Parliament and of the Council of 16 April 2014 on fluorinated greenhouse gases and repealing Regulation (EC) No 842/2006, the scope of refrigerants, which have so far been commonly used is very limited. All preferred refrigerants are mostly flammable and explosive, and they include R32, R1234yf, R1234ze, R290 (propane), R600a (isobutane), R717 (ammonia). However, it should be noted that refrigerants such as R32, R1234yf, R1234ze are classified as mildly flammable and has been created for them, in accordance with ISO 817 standard, special group called A2L. It is also worth noting that the new classification moved ammonia to the group B2L - that means is toxic and mildly flammable. The article focuses on defining the conditions in which there is possible to build safely split installation in which the propane is a refrigerant. It turns out that small splits are devices which can be used safely with R290 in most cases.

Textile industry in the nineteenth century of the British empire was one of the milestone industries which center around cotton mills. The development of this industry attracted many people who wished to increase their life’ standard to migrate to area near the factories located in order to work there. As much as giving revenue for the country, these factories also gave impact to the environment as well as people living and working in it. There were three things behind the environmental impact during the Victorian era of textile industry, fire hazard, mills’ poor conditions and factory bill. Flammable materials, like raw cotton which mainly used in this industry, and high temperature room caused the factories engulfed in fire. The lacked protection from fire of the factories’ construction then led to a new building method being introduced and applied called the “Fireproof Construction”. Poor health condition of the workers who worked in high humidity and temperature of cotton mills brought a creation of factory bill (Factory Act) being passed. However, the act that was supposed to act as a regulation for factories owners to offer their worker a much more suitable place to work was hardly fully implied during this time. The writer used literature review method in collecting data. This article therefore intended to deliver the reader about the environment situation in the cotton factories while also giving the idea on how hardly an ideal comfort was achieved.

High global warming potential (GWP) refrigerants for refrigeration and heat pump systems or organic Rankine cycle systems are being phased out because of their impact on climate change, such as R134a, R410A and R404A. So it is urgent to find the refrigerants with excellent environmental protection performance. Firstly, nearly 40 alternative refrigerants, including pure refrigerants and mixed refrigerants, are classified according to their environmental and safety characteristics. Secondly, the performance parameters of some typical alternatives, such as refrigerating capacity, COP, safety and environmental protection, are comprehensively compared. It can be concluded that R513a and R466A have good comprehensive performance as alternative refrigerants of R134a and R410A respectively, while those alternatives to R404A have both advantages and disadvantages. The application and technical characteristics of R32, some typical HFOs, natural refrigerants and mixtures are summarized and analyzed. In addition, our group has carried out experimental and theoretical research on the flammability of low GWP and flammable refrigerants such as R1234yf, R161, R290, R600a and R1150, and found that hydrocarbons are more difficult to be inhibited than halogenated hydrocarbons. Finally, a new research idea on the risk of refrigerant explosion is put forward, which can cover the refrigerant leakage, combustion and risk aversion.

Development of gas sensors for detecting toxic, harmful, flammable, and explosive gases has always been very popular research direction. Graphene is considered potential chemi-resistive gas sensing material owing to its high specific surface area and good conductivity. Recent studies have shown that graphene-based gas sensors doped with metals, polymers, and metal oxides have good sensitivity, selectivity, and repeatability. Moreover, they are superior to traditional gas sensors. In this review, sensing mechanism of such composite sensors is introduced. In addition, research status on various sensors is discussed, and their advantages and disadvantages are summarized. Possible improvement methods are proposed as well. Finally, several common problems characteristic of graphene-based gas sensors are described, together with some critical ideas for improving their performance.