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Code of Conduct for the Laboratory Area 1. It is prohibited to eat, store food, beverages, or other personal items in the laboratory； One must not do anything unrelated to experiments and research. 2. Smoking is prohibited throughout the laboratory area (including indoors, corridors, elevator lobbies, etc.). 3. No outsiders are allowed to enter the laboratory without the permission of the laboratory management. 4. Be familiar with the evacuation routes and emergency response procedures in case of emergencies, and know the locations of first-aid kits, fire extinguishing equipment, emergency eye wash stations, and shower units. Keep in mind the emergency numbers 119/120/110. 5. Keep laboratory doors and corridors unobstructed, minimize the amount of reagents stored in the laboratory, and it is strictly prohibited to store highly toxic substances without permission. 6. Wash your hands before leaving the laboratory; do not wear lab coats or gloves when entering public areas such as the cafeteria, library, meeting rooms, and offices. 7. Keep the laboratory clean and tidy; after experiments, clean, dry, and store experimental equipment and utensils promptly. There should be no excessive accumulation of items inside the room or on the workbenches, and the workbenches should be cleaned at least once a day. 8. In case of any doubts during experimental work, consult the person in charge of the laboratory or the instrumentation promptly; do not proceed with operations blindly. 9. It is strictly prohibited to leave the experiment site for long periods of time during the experiment. 10. When conducting certain dangerous experiments at night or on holidays, there must be at least two people in the room to ensure the safety of the experiment. Storage of chemicals 1. All containers holding chemical substances must be equipped with clear and permanent labels indicating their contents and potential hazards. 2. All chemicals should have a Safety Data Sheet. 3. Be familiar with the properties and potential hazards of the chemicals being used. 4. Chemicals that are unstable during storage or prone to forming peroxides require special labeling. 5. Chemicals should be stored at an appropriate height; chemicals must not be stored in fume hoods. 6. The storage location of containers holding corrosive liquids should be as low as possible, and collection trays should be used to prevent spills from causing safety accidents. 7. Store unstable chemicals separately, with the purchase date indicated on the label. Store pharmaceutical reagents that may undergo chemical reactions separately to prevent interactions that could produce toxic fumes, fires, or even explosions. 8. Volatile and toxic substances require special storage conditions; highly toxic chemicals must not be stored in the laboratory without permission. 9. Large quantities of flammable solvents must not be stored in the laboratory; only the amount needed should be acquired. Unused entire bottles of reagent must be stored in a place away from light and heat sources. 10. When handling hazardous chemicals, it is necessary to wear work clothes, protective goggles, closed-toe shoes that cover the toes, and long hair must be tied back. 11. Corrosive chemicals, toxic chemicals, organic peroxides, self-igniting substances, and radioactive materials must not be stored together, especially bleach, nitric acid, perchloric acid, and hydrogen peroxide. Use of organic solvents 1. Flammable organic solvents: Many organic solvents can cause fires or even explosions if not handled properly. A mixture of solvent and air, once ignited, spreads rapidly; its intense flame can instantly ignite flammable materials. In areas with an adequate supply of oxygen – such as when an oxygen cylinder leaks – the fire becomes even more violent, capable of setting some non-flammable substances on fire as well. When vapors of flammable organic solvents mix with air and reach a certain concentration range, explosions can even occur. When using flammable organic solvents, the following precautions should be observed: (1) Place the containers of flammable liquids on lower shelves. (2) Keep the container sealed; open its lid only when it is necessary to pour out the liquid. (3) Flammable organic solvents should be used in a fire-free area with good ventilation (such as a fume hood), being careful not to use excessive amounts. (4) When storing flammable solvents, the amount stored should be reduced as much as possible to avoid danger. (5) When heating flammable liquids, it is best to use an oil bath or a water bath; open flame heating should not be used. (6) When using flammable organic solvents, special attention should be paid to the temperature of use and the experimental conditions. Table 1 shows the ignition points, auto-ignition temperatures, and combustion concentration ranges of commonly used flammable organic solvents. (7) The combustion of a mixture of chemical gases and air can cause explosions (for example, the energy released by the combustion of 3.25 grams of propane gas is equivalent to that of 10 g**), so combustion experiments must be carried out with caution. (8) During use, be vigilant against the following common sources of fire: open flames (Bunsen burners, welding torches, oil lamps, fireplaces, lighters, matches), sparks (power switches, friction), heat sources (electric heating plates, filaments, electric heating jackets, ovens, radiators, portable heaters, cigarettes), and static electricity. 2. Toxic organic solvents: The toxicity of organic solvents manifests itself as local **irritation or disruptions in the functioning of the entire body when these solvents come into contact with the human body or are absorbed by it. All volatile organic solvents, whose vapors are in contact with the human body for long periods at high concentrations, are always toxic; for example, primary alcohols (except methanol), ethers, aldehydes, ketones, certain esters, and benzyl alcohol-based solvents can damage the nervous system ； Methyl esters of carboxylic acids and formates can cause pulmonary toxicity ； Benzene and its derivatives, ethylene glycol compounds, etc., can cause blood poisoning ； Halohydrocarbons can cause liver and metabolic poisoning ； Tetrachloroethane and ethylene glycol derivatives can cause severe kidney toxicity, among other issues. Therefore, the following points should be noted when using it: (1) Try to avoid direct contact between the skin and organic solvents, and be sure to use appropriate personal protective measures; for more details, see: Personal Protective Measures in the Laboratory. (2) Be sure to maintain good ventilation in the experimental area. (3) If toxic organic solvents spill during use, all sources of fire should be extinguished depending on the amount spilled. The personnel present in the laboratory should be alerted to use fire extinguishers, and then the spilled material should be cleaned up with absorbents, bagged, sealed, and treated as waste solvent. Use of electricity: 1. It is strictly prohibited to wire electricity privately in the laboratory. 2. Before using a socket, it is necessary to know its rated voltage and power; the socket must not be used beyond its capacity. 3. It is prohibited to connect additional power strips in series on a power strip. Multiple electrical appliances should not be used simultaneously on the same power strip for an extended period of time. 4. Large-scale instruments and equipment must be connected to separate sockets. 5. Temporary power strips must not be used for extended periods. 6. Save electricity. Before leaving the lab at the end of the workday or on holidays, electrical appliances such as air conditioners, lighting fixtures, and computers should be turned off. Even on weekdays, these appliances should be turned off whenever they’re not needed. Water usage: Laboratory water is divided into three categories: tap water, pure water, and ultrapure water. The following points should be noted when in use: 1. Save water by taking only what is needed. 2. Select the appropriate water based on the mass requirement for water in the experiment. To clean glassware, use tap water first and rinse with pure water at the end ； Ultra-pure water should be used for chromatography, mass spectrometry, and biological experiments (including buffer preparation, hydroponics, preparation of microbial media, and chromatography and mass spectrometry flow cells). 3. Neither ultra-pure water nor pure water should be stored; use it as needed. If not used for an extended period, before reactivating it, turn on the water supply valve to allow ultrapure or pure water to flow out for about a few minutes before using it again. 4. Be sure to turn off the faucet after use. Use of liquid nitrogen: Liquid nitrogen is commonly used as a refrigerant. Refrigerants can cause frostbite; even a small amount coming into contact with the eyes can lead to blindness. The gases produced by liquid nitrogen can evaporate rapidly, resulting in a lack of oxygen in the surrounding air. When using and handling liquid nitrogen, pay attention to the following: 1. Wear insulated protective gloves. 2. Put on a long-sleeved lab coat that is longer than the knees. 3. Wear shoes that cover the ankles without exposing the tops of the feet, put on protective glasses, and wear a face shield if necessary. 4. Maintain smooth airflow in the environment. Use of cleaning solutions: Cleaning solutions are divided into acidic solutions (sulfuric acid solutions containing sodium dichromate or potassium dichromate), alkaline solutions (sodium hydroxide-ethanol solutions), and neutral solutions (common detergents). 1. The acidic cleaning solution can be placed in a glass tank, while the alkaline cleaning solution can be placed in a plastic bucket. 2. When using an alkaline cleaning solution, the fused joints of glass instruments should be separated before placing them in the cleaning solution container, to prevent the joints from being corroded by the alkaline substance and sticking together. Glassware should be pre-washed with acetone and water before being placed in the alkaline solution. Use of instruments, facilities, and equipment 1. Proper use of glassware – Using various types of glassware is very important for preventing injuries to people. Broken glassware is not allowed to be used in the laboratory. Glassware that cannot be repaired should be disposed of as waste. Chemicals remaining in glassware should be removed before repairing it. When using various glassware, laboratory personnel should pay attention to the following points: (1) Wear protective gloves when attaching glass tubes to rubber stoppers or rubber tubes. First, smooth the ends of the glass tube with fire, and apply water or grease to the joints as a lubricant. Do not try to pull together glassware that is stuck together, to avoid injuring your hand. (2) The outside of the Dewar flask should be covered with a layer of tape or some other protective layer to prevent glass shards from scattering in case it breaks. Glass distillation columns should also have a similar protective layer. When using glassware for operations at non-atmospheric pressures (above or below atmospheric pressure), it should be done behind a protective shield. (3) Broken glass should be placed in special trash bins. Broken glass should be rinsed with water before being put into the trash bin. (4) When performing vacuum distillation, appropriate protective measures (such as plexiglass baffles) should be used to prevent glassware from exploding or breaking and causing injury to personnel. (5) Ordinary glassware is not suitable for pressure reactions; there is a significant risk even at low pressures, therefore the use of ordinary glassware for such reactions is prohibited. (6) Do not place heated glassware on a too-cold surface to prevent the glass from breaking due to sudden temperature changes. 2. Rotavapor Apparatus: The rotavapor apparatus is a commonly used instrument in laboratories. The following points should be taken into consideration when using it: (1) The pressure suitable for a rotavapor apparatus is generally 10–30 mmHg. (2) All connection parts of the rotary evaporator should be secured using special clamps. (3) The solvent volume in the rotary evaporator flask should not exceed half. (4) The rotary evaporator must rotate at an appropriate speed. 3. Vacuum pump: A vacuum pump is a device used for filtration, distillation, and vacuum drying. There are three common types of vacuum pumps: air pumps, oil pumps, and circulating water pumps. Water pumps and oil pumps can achieve a vacuum level of 20–100 mmHg, while high-vacuum oil pumps can reach a vacuum level of 0.001–5 mmHg. The following points should be noted when in use: (1) A cold trap must be connected in front of the oil pump. (2) The water in the circulation pump must be replaced frequently to prevent residual solvents from being ignited by motor sparks. (3) Before use, cool the distilled liquid first, then release gas slowly; once equilibrium is reached, close it. (4) The oil pump must have its oil changed regularly. (5) A rubber hose should be connected to the exhaust port on the oil pump and led to the fume hood. 4. Fume hood: The function of a fume hood is to protect laboratory personnel from toxic and harmful gases, but it cannot remove all toxic gases. The following points should be noted when in use: (1) Chemicals and laboratory equipment must not be placed at the exit. (2) The ventilation must not be turned off while conducting experiments. 5. Thermometers: Thermometers generally include alcohol thermometers, mercury thermometers, quartz thermometers, and thermocouples. Low-temperature alcohol thermometer measurement range: -80°C ~ +50℃ ； Alcohol thermometer measurement range: 0°C ~ +80℃ ； The range of a mercury thermometer is 0°C to +360°C℃ ； The measurement range of high-temperature quartz thermometers is 0°C to +500°C; thermocouples are not commonly used in laboratories. Lab personnel should choose an appropriate thermometer. Thermometers should not be used as stirrers, to avoid breaking or damage that could cause other hazards. After a mercury thermometer breaks, most of the mercury should be sucked up using a straw; it should then be placed in a suitable sealed container and labeled, awaiting disposal by a company specialized in handling waste chemical reagents. The remaining mercury should be covered with sulfur, and cleanup should take place after a few days. 6. Gas cylinders: The substances inside gas cylinders are often under high pressure, and accidents such as explosions can occur if the cylinders are overturned, exposed to heat, or subjected to improper handling. In addition to being explosive and prone to spraying, compressed gases in cylinders are often flammable, toxic, and corrosive. Therefore, when using gas cylinders, the following points should be noted: (1) Characteristics of normal safe gas cylinders: ① The cylinder surface must have a clear label indicating the name of the gas. ②All gas cylinders are marked with colors. ③All gas cylinders must be equipped with pressure relief valves. (2) Storage of gas cylinders: ① Compressed gases are classified as Class 1 hazardous materials; try to minimize the number of cylinders stored in the laboratory, and hydrogen gas must not be stored there at all. ②Gas cylinders should be placed upright against a wall, with measures taken to prevent them from toppling over ； Avoid exposure to sunlight, keep away from heat sources, corrosive materials, and potential impacts ； At the same time, gas cylinders must not be placed in corridors or lobbies to prevent obstacles during emergency evacuations and other accidents. ③Flammable gas cylinders and oxidizing gas cylinders must not be stored together ； Flammable and combustible pressure cylinders must be kept at a distance of at least 10 meters from open flames ； Cylinders containing flammable and toxic gases must be placed outdoors, in properly specified and secure metal cabinets. (3) Use of gas cylinders: ① Before opening the pressure regulator, clean the water and dust from the outlet of the cylinder valve. After using the gas cylinder, close its main valve and release any excess pressure in the pressure regulator. A safety cap must be worn (except in cases where it is not required by the original design) to prevent damage to the valve. Care must be taken when removing the safety helmet to avoid accidentally opening the main valve of the cylinder. ②The gas cylinders must not be completely emptied (especially those containing acetylene, hydrogen, or oxygen); a certain positive pressure must remain. ③Gas cylinders must be used in a well-ventilated area, with the pressure relief valve and outlet valve in good condition; local ventilation should be enhanced when dealing with toxic gases. ④When using cylinders containing toxic or corrosive gases, protective goggles, a mask, gloves, and an apron should be worn. It is strictly prohibited to strike or collide pressure gas cylinders. ⑤Oils or greases must not be applied to the pressure regulators, valves, and piping of oxygen cylinders. ⑥Gas cylinders should be transported using a cylinder cart and kept upright, with the pressure relief valve tightly closed. 7. In solid-liquid separation, centrifuges are a very effective method, especially when separating suspensions containing very small solid particles. When using it, pay attention to the following points: (1) When using a centrifuge, the centrifuge tubes must be symmetrically balanced; otherwise, water should be used as a counterweight to maintain balanced rotation of the centrifuge. (2) Before starting the centrifuge, its cover should be closed. It should be started at a lower speed first, and then the speed adjusted to the desired level. (3) When the centrifugation is complete, one must wait until the centrifuge has stopped completely before opening the lid; it is absolutely forbidden to open the lid or touch the rotating parts of the centrifuge before it has fully stopped. (4) Glass centrifuge tubes require high quality; plastic centrifuge tubes should not be used with hot solutions or organic solvents to prevent deformation of the tubes during centrifugation. (5) The solution in the centrifuge tube should generally be kept at about half of the tube’s volume; too much liquid must not be used to prevent it from spilling out during centrifugation. 8. When using a syringe, be careful to avoid needle punctures and barrel breaks that could injure your hands; the needle and barrel should be tightened to prevent leaks. Used syringes must be cleaned promptly. Useless syringes should be destroyed before disposal to prevent misuse by others. 9. The refrigerators in the refrigerator and freezer laboratories are not equipped with explosion-proof devices, and therefore are not suitable for storing flammable, explosive, or volatile solvents. (1) It is strictly prohibited to store personal food in refrigerators and freezers. (2) All low-boiling-point reagents stored in refrigerators and freezers must be properly labeled. (3) All containers stored in refrigerators and freezers must be sealed, and the refrigerators should be cleaned regularly to remove unnecessary samples and reagents. The main safety accidents in the laboratory: 1. Fire accidents – The cause is forgetting to turn off the power supply, which results in equipment or electrical appliances remaining powered on for too long; this leads to excessive heat and subsequent fires ； Careless operation or improper use can cause a flame to come into contact with flammable materials, leading to a fire ； The aging power supply lines and overloading lead to heating of the lines, which in turn causes fires ； Losing cigarette butts, coming into contact with flammable materials, can cause fires and such. Such accidents are common and can occur in any laboratory. 2. Cause of the explosion: Violation of operating procedures, which led to the ignition of flammable materials and consequently an explosion ； The equipment is aging, and it has faults or defects that lead to the leakage of flammable and explosive substances, which can explode when exposed to sparks. Such accidents often occur in laboratories that have flammable and explosive materials as well as pressure vessels. 3. Causes of biological safety incidents: Negligences in the management of microbiology laboratories and accidents can not only lead to infections among laboratory staff but also cause environmental pollution and widespread infections among the general population ； Waste generated in biological laboratories is even more dangerous than that from chemical laboratories, as biological waste contains infectious bacteria, viruses, chemical pollutants, and radioactive substances that can pose a serious threat to human health and the environment. 4. Cause of the poisoning incident: Violation of operating procedures by bringing food into a laboratory containing toxic substances, resulting in accidental ingestion and poisoning ； The aging of equipment and facilities, along with existing faults or defects, can lead to the leakage of toxic substances or the inability to discharge toxic gases, resulting in poisoning ； Poor management has led to the leakage of toxic substances, causing environmental pollution ； The wastewater discharge pipeline is blocked or rerouted improperly, resulting in the release of toxic wastewater without treatment and causing environmental pollution. Such accidents often occur in chemical and chemical engineering laboratories that contain chemicals and highly toxic substances, as well as in laboratories that emit poisonous gases. 5. Causes of equipment damage: Line failures or lightning strikes lead to sudden power outages, preventing the heated medium from returning to its original state as required and thus causing equipment damage ； High-speed moving equipment can be damaged due to collisions or compressions resulting from improper operation. Such accidents often occur in laboratories that use electric heating. 6. Causes of mechanical and electrical injury accidents: Improper operation or lack of protection, resulting in crushing, throwing, and collision injuries ； Violations of operating procedures, or faults and defects resulting from the aging of equipment and facilities, can lead to electric leakage, electric shock, and injuries caused by arc sparks ； Improper use can cause harm to people from high-temperature gases and liquids. Such accidents often occur in mechanical laboratories with high-speed rotation or impact movements, electrical laboratories where work is carried out on live circuits, and some laboratories that generate high temperatures. 7. Reasons for theft of equipment or technology: High turnover of laboratory staff makes it difficult to manage equipment and technology, and the weak safety awareness among laboratory personnel provides criminals with an opportunity to take advantage of the situation. Such accidents are common in laboratory safety; they not only cause financial losses and disrupt the normal operation of the laboratory, but may also lead to the leakage of core technologies. Preventive measures: 1. Eliminate human-related hazards. The main participants in experimental work are humans, and human factors related to safety are the primary cause of safety accidents in laboratories. Therefore, only by starting with \"people\" and using various means to improve the safety awareness and competence of laboratory staff can potential safety hazards be minimized. ※**Colleges and universities place great emphasis on laboratory safety. For example, before using controlled materials or instruments, graduate students must undergo mandatory safety training and examinations organized by the university’s Safety and Environmental Affairs Office; only those who pass can enter the laboratory. Safety training must also be mandatory for undergraduate students in science and engineering fields; this includes both face-to-face lectures and online courses, as well as general safety training sessions on fire prevention and evacuation. Tsinghua University has developed an online learning and examination system for laboratory safety courses, utilizing modern network information technology and abundant online resources to conduct laboratory safety education. 2. Establish a safe environment – A safe environment is an important factor in ensuring laboratory safety. To create such an environment, efforts should be made both at the hardware and software levels. In terms of hardware: laboratories (buildings) must be equipped with comprehensive safety facilities, such as fire-fighting equipment, alarm systems, emergency sprinklers, eye wash stations, first-aid kits, and waste collection systems. Safety passages should be inspected regularly to ensure they remain unobstructed, and to guarantee that the electricity and water used for experiments are safe and of satisfactory quality. In terms of software: identify the safety officers for each laboratory, post clear signs indicating the potential hazards in each laboratory, provide detailed information on the safety precautions and usage rules for various instruments and equipment, and clearly indicate the hazards associated with chemicals as well as the emergency response measures. Regular safety inspections should be carried out, safety studies and competitions related to safety knowledge, experimental techniques, and management should be organized, strict reward and punishment systems should be established, in order to foster a safe working environment. 3. Improve the institutional framework and enhance safety awareness. Establishing a comprehensive and clear set of laboratory management regulations and enforcing them strictly is an important guarantee for the sustainable development of laboratory safety efforts, as well as a necessary condition for the operation of safety access systems. ※**Universities generally establish university-level committees for safety and environmental protection, headed by the vice president for administration. These committees are responsible for formulating the university’s safety policies, rules, and guidelines, improving various regulations and safety and environmental protection facilities, and setting up a department for safety and environmental affairs to handle day-to-day management, thereby ensuring that safety management tasks are carried out effectively. Chemical Laboratory Safety Management Regulations 1. Theft prevention: Strengthen security measures, conduct regular inspections, and close any loopholes. Non-staff members are not allowed to enter the instrument room; close the doors and windows immediately when no one is inside. Visitors are not allowed in the instrument room, and no one may stay there. Visits are prohibited without the approval of the supervisors. Personal valuables must not be kept in the office. In the event of a theft, preserve the scene and report it to management and the security authorities promptly. 2. Fire and explosion prevention: The instrument room is equipped with fire prevention devices such as fire extinguishers and sand boxes. It is strictly prohibited to start a fire for heating inside the instrument room. Flammable and explosive chemicals should be stored separately in a proper manner. Storage procedures should be tailored to the properties of each chemical, with attention paid to safety. When conducting chemical experiments, it is necessary to follow the operating procedures strictly to prevent accidents such as fires and explosions. 3. Water resistance: The upper and lower drainage systems in the laboratory must remain unobstructed. The laboratory building should be equipped with a main water supply valve, while biological and chemical laboratories should have separate valves. The main valve is operated by the duty personnel, while the separate valves are operated by the relevant management staff. In winter, it is necessary to insulate and drain the water pipes to prevent them from freezing and bursting, which could lead to flooding. 4. Poison prevention: The laboratory contains toxic substances, and poisonous gases and liquids are generated during experiments; therefore, it is necessary to take proper measures for poison prevention. Toxic substances should be properly kept and stored, and toxic residues remaining after experiments must be handled appropriately. Special warehouses for hazardous materials should be established; dangerous substances such as flammable, toxic oxidizers, and corrosives must be stored in dedicated cabinets separately. Chemical hazards must be inspected and registered before being stored, and regular checks must be carried out after storage under strict management, adhering to the \"five pairs of controls\" principle: dual-person management, dual-person handling for receipt and dispatch, dual-person authorization for material withdrawal, dual-person accounting, and dual-person locking. The operating procedures were strictly followed during the experiments; the generation of toxic gases had to take place in a fume hood. The student laboratories are equipped with exhaust fans to ensure good ventilation inside the rooms. Waste liquid bottles are available on the students’ experiment tables, while waste liquid containers are provided in the chemistry laboratory. Waste liquid treatment tanks are located near the laboratories to prevent toxic substances from spreading and harming humans and animals. 5. Safe electricity use: The wiring layout in the laboratory should be reasonable, scientific, and convenient. The building is equipped with a main power switch, with sub-switches at each floor, as well as electrical shock protection devices. The main switch is controlled by the person on duty each day, while the individual switches are controlled by the managers of each room, who check their status at the start and end of each workday. The main power switch for students is located near the lectern, and it is the instructor’s responsibility to control its activation and deactivation. Laboratory circuits and electrical equipment must be regularly inspected to ensure safety, and must never operate while faulty. In the event of a fire involving electrical equipment, the power supply should be cut off immediately, and the fire should be extinguished using sand or a fire extinguisher. Do not use water or a foam fire extinguisher to put out the fire before turning off the power supply. In the event of an electric shock, the power supply should be cut off immediately, artificial respiration should be administered promptly, and the victim should be rushed to the hospital for treatment. Chemistry Laboratory Rules 1. The laboratory must be kept quiet; loud talking and noise are strictly prohibited. 2. Before the experiment, students must complete the preparatory work in advance; upon entering the laboratory, they should do so in an orderly manner and take their designated seats. 3. Before the experiment, the teacher must explain to the students the content, purpose, requirements, and procedures of the experiment. 4. At the start of the experiment, students should first check whether all the instruments and reagents are available; they must not replace them arbitrarily, and any issues found should be reported promptly. 5. The experiment must be carried out step by step, with close observation and thorough recording; the experiment report should be written promptly after class. 6. During experiments, it is necessary to take good care of the instruments and use reagents sparingly; any damage or loss of instruments caused by violations of operating procedures must be compensated for. 7. When the experiment is over, the equipment must be organized or cleaned to keep the area tidy; one may leave only after the instructor gives the permission. 8. These guidelines are presented to students before the first experiment of each semester. Rules and Regulations for the Chemical Instrument Room 1. Staff working in the instrument room must remain at their posts, paying attention to fire prevention, theft prevention, and poison prevention. At the end of each semester, it is necessary to conduct an inventory check of the instruments and chemicals to ensure that the records match the actual items on hand. 2. Teaching equipment shall not be lent to individuals or other organizations for use. In cases where lending is absolutely necessary, it must be approved by the school’s relevant supervisor, and the equipment must be returned on time; in the event of any damage, compensation shall be paid at the appropriate price. 3. Teachers must go through the borrowing procedure when taking experimental instruments and chemicals; they should return them immediately after use and must not take them to the office to avoid damage or loss. Any damage to instruments during experiments must be recorded accurately. 4. For group experiments, notification should be given one week in advance, while for demonstration experiments, the instructor should be informed a day in advance so that the experiments can be carried out on time. 5. Unauthorized persons are strictly prohibited from entering the equipment room. 6. Strict rules must be followed regarding the storage and use of hazardous chemicals and valuable instruments; if any hazardous chemicals are lost, it is necessary to report this to the school authorities promptly. 7. Smoking and eating are strictly prohibited in the equipment room. 8. Flammable and explosive waste liquids should be poured into designated containers for centralized disposal. 9. It is important to take good care of public property and instruments; chemicals should be used sparingly, and any damage to instruments must be recorded accurately, with appropriate compensation required in such cases. The “Eight Precautions” for Laboratory Safety Management. In recent years, China has placed increasing emphasis on work safety; the Work Safety Law of the People’s Republic of China was revised in 2014. Article 54 of this law states that employees must strictly abide by their employer’s work safety regulations and operating procedures during their work, comply with management instructions, and wear and use personal protective equipment properly. Depending on the characteristics of the laboratory, its safety involves aspects such as water resistance, fire prevention, poison prevention, corrosion protection, electric shock prevention, explosion prevention, environmental pollution prevention, and protection against reckless handling. I will briefly discuss these aspects; I believe that by implementing these measures, the occurrence of safety accidents can be effectively reduced and prevented. 1. Water resistance: Every laboratory is equipped with disposable water, pure water, highly pure water, as well as instruments for water production such as distillers and pure water systems. During use, workers may forget to turn off the faucet, or they might open the faucet after a sudden water cutout and forget to close it. Our laboratory experienced a flooding incident once; it happened because on the day when the water supply was cut off, someone left the faucet on without turning it off, which resulted in an excessive flow of water. Additionally, the drainage outlet was blocked, leading to severe flooding in the laboratory. It took an hour to clean up all the water from the laboratory. It is also necessary to regularly check the water production equipment to prevent leaks. 2. The fire safety laboratory is equipped with various heating devices such as alcohol lamps and electric stoves, as well as instruments that can generate fire, like FID gas chromatographs. All of these can pose safety risks; therefore, when using such items, we need to take into account the three elements of combustion – an ignition source, a combustible material, and an oxidizing agent. When using fire, it is necessary to remove any oxidizing agents located near the ignition source in order to prevent fire accidents. When fighting a fire, it is also necessary to take into account the three elements of combustion; eliminating one of them can stop the burning. Fires are classified into four categories: A, B, C, and D. The type of fire extinguisher to be used for each category must be specified, and every laboratory must be equipped with fire extinguishers, which also need to be inspected regularly. 3. Poison prevention: I believe every laboratory uses toxic reagents. Therefore, when working with such substances, it is necessary to understand their physical and chemical properties, as well as the proper methods of use and emergency procedures. All drugs and reagents must be labeled in accordance with their contents, and highly toxic substances must strictly adhere to the \"five doubles\" system (double custody, double distribution, double locking, double record-keeping, and double inspection). For example, when preparing sulfuric acid solutions, we must wear corrosion-resistant latex gloves and protective goggles, use glass containers for storage, add the acid to the water rather than adding water to the acid, stir while adding it, and then transfer it to a reagent bottle after it has cooled down. If sulfuric acid gets on the skin, wipe it clean with a cloth and then rinse thoroughly with plenty of water. For tasks like preparing sulfuric acid solutions, we need to consider various precautions before, during, and after the operation. 4. Reagents commonly used in corrosion prevention laboratories, such as sulfuric acid solution and sodium hydroxide solution, are all corrosive. Using corrosive solutions will damage our lab benches and experimental equipment. Therefore, when using these solutions, we must take proper protective measures; if the solution spills on the lab bench or experimental equipment, it should be wiped clean immediately with a cloth. The waste liquid after use should be collected in containers rather than being discharged carelessly. 5. Preventing electric shock: We need to be careful to avoid electric shock both at work and at home. Starting with electrical installations, power sockets must be equipped with ground wires, while high-power instruments and electrical devices must be connected to circuit breakers. The entire electrical system in the laboratory must have leakage protection switches ； Secondly, when using electrical equipment, one should not touch the switches and power sources with wet hands. It is necessary to follow the operating procedures of the electrical equipment strictly. When performing repairs or maintenance on the instruments, the \"three-step process\" must be followed: shut down the equipment, disconnect the power, and place a sign in place ； Finally, turn off the power of the instruments and equipment after use to return them to their condition before use. 6. Explosive and flammable drugs include picric acid, perchloric acid, hydrogen peroxide, etc. Such drugs should be stored separately and not kept together with other flammable materials. When heating glassware in an electric furnace, the water on the outer surface of the glassware must be wiped clean, and glass beads should be used to prevent the glassware from breaking. When performing explosive operations, such as analyzing explosive gases with an oxygen analyzer, a protective mesh must be installed around the explosion bottle. It is strictly prohibited to bake flammable and explosive items in the oven. 7. Pollution prevention: The waste generated in a typical laboratory includes waste liquids, waste gases, and solid waste. Although the waste generated in the laboratory is much less than that in the production areas, as analysts, it is necessary for us to start with ourselves and take action at every level to protect the environment around us. The most common type of waste generated in the laboratory is liquid waste. The unused solutions after use cannot be discharged directly into the waste liquid tank; instead, they are first collected in waste liquid containers for centralized treatment. For example, the pH of the waste liquid is adjusted, and waste liquids containing heavy metals are neutralized by using another type of waste liquid before being discharged into the tank. This approach reduces the difficulty of wastewater treatment, lowers the costs associated with it, and also helps to protect the environment ； Waste includes discarded medications and used reagent bottles, etc. Discarded medications must be collected together for proper disposal and cannot be thrown directly into the trash; used reagent bottles should be rinsed with water before being discarded. Treating exhaust gases is somewhat more difficult, but there are some simple methods that can also help protect the environment, such as placing activated carbon in the laboratory or using potted plants to absorb exhaust gases. Our small actions can make a big difference in protecting the environment. 8. Prevent rough handling. Rough handling means working without following the operating procedures. Rough handling is the biggest safety hazard, and the most effective way to prevent it is to strictly follow the operating procedures. It can be said that every set of operating procedures is the result of the valuable experience and sacrifices of our predecessors; therefore, we must follow these procedures in every step of our operations. Some people, after working for a long time and feeling that they have experience in their job, sometimes slack off, not realizing that such behavior is precisely a major factor contributing to accidents. The three elements of an accident are unsafe human behavior, unsafe conditions of objects, and environmental factors. By controlling these three elements, accidents can be avoided.