安全性及环保问题自热食品通常是化学物质与水（或水溶液）进行反应，水遇到

Safety and environmental issues <br>Self-heating food usually reacts between chemical substances and water (or aqueous solution). After water encounters a heat source, it will quickly rise to the boiling point and release a large amount of water vapor. If these vapors are in a sealed package, there will be May cause an explosion. Some self-heating food packaging has vent holes to avoid this problem, but you should still pay attention when using it. In addition, the reaction of some heat sources with water may produce harmful gases such as carbon monoxide, which may endanger the lives of users, so please pay attention to ventilation when using. <br>Since self-heating food has the aforementioned safety hazards, some places will prohibit passengers from carrying or using self-heating food on public transportation such as airplanes or high-speed rail. For example, the "Guangxi Zhuang Autonomous Region Railway Safety Management Regulations" clearly prohibits "using self-heated food that can induce smoke alarms on EMU trains", and offenders may impose a fine of RMB 500 to RMB 2,000. <br>In addition, the chemical substances contained in self-heating food may produce some harmful substances that are unfavorable to the environment after the reaction, and the need for "self-heating" has also greatly increased the weight of disposable packaging.

Safety and environmental issues<br>Self-heating foods are usually chemicals that react with water (or aqueous solutions), which heat up rapidly to boiling point when they encounter a heat source, while releasing large amounts of water vapor that can cause an explosion if they are in a sealed package. Some self-heating food packaging will have exhaust holes to avoid this problem, but should still be taken care when using. In addition, some heat sources and water reactions may produce carbon monoxide and other harmful gases, may cause life-threatening to the user, so use should pay attention to ventilation.<br>Due to the above safety risks of self-heating food, some places will prohibit passengers from carrying or using self-heating food on public transport such as airplanes or high-speed rail. For example, the Regulations on Railway Safety Management of Guangxi Zhuang Autonomous Region expressly prohibit "the use of self-heated food on train sets that can induce smoke alarms", violators may be fined between RMB 500 and RMB 2000 for individuals.<br>In addition, chemicals contained in warm foods may produce environmentally harmful substances after reaction, and the need for "self-heating" has significantly increased the weight of disposable packaging.

Safety and environmental protection<br>Self heating food is usually a reaction between chemical substances and water (or aqueous solution). When water encounters a heat source, it will quickly rise to boiling point and release a large amount of steam. If these steam are in the sealed package, it may cause explosion. Some self heating food packages will have vent holes, which can avoid this problem, but it should be paid attention to when using. In addition, some heat sources may react with water to produce harmful gases such as carbon monoxide, which may endanger the life of users. Therefore, attention should be paid to ventilation when using.<br>Due to the above-mentioned safety risks, some places will prohibit passengers from carrying or using self heating food on public transport vehicles such as aircraft or high-speed rail. For example, the "Regulations on railway safety management of Guangxi Zhuang Autonomous Region" explicitly prohibit "the use of self-contained heated food that can induce smoke alarm on multiple units", and the violator can be fined more than 500 yuan and less than 2000 yuan.<br>In addition, the chemical substances contained in self heating food may produce some harmful substances harmful to the environment after reaction, and the demand for self heating also greatly increases the weight of disposable packaging.<br>