Personal Protective Requirements

• Lab Coat: Wear full-coverage, acid- and alkali-resistant, easy-to-clean lab coats. Avoid wearing loose or static-generating clothing in the laboratory.
• Gloves: Choose suitable gloves (e.g., nitrile, latex, PVC) based on the experiment. Ensure no damage and replace them regularly to prevent cross-contamination.
• Eye and Face Protection: When performing experiments with splashes or harmful gases, wear safety goggles or face shields.
• Respiratory Protection: Wear gas masks or air-purifying respirators when handling toxic gases or dust.
• Hearing Protection: Use earplugs or earmuffs in high-noise environments.
• Full-body Protection: During high-risk experiments, wear full-body protective suits, including hoods, shoe covers, and gloves.
• Maintenance and Replacement: Regularly check the condition of protective equipment, and replace damaged or contaminated items. Dispose of single-use items after use.

Laboratory Safety Classification

Biosafety Levels (BSL): Biosafety levels for laboratories conducting in vitro operations are classified as BSL-1 to BSL-4.

• P1 (Protection Level 1): A basic laboratory suitable for work with agents that pose minimal potential hazards to humans, animals, plants, or the environment. These agents are not known to cause disease in healthy adults, animals, or plants.
• P2 (Protection Level 2): A basic laboratory suitable for handling agents of moderate potential hazard to humans, animals, plants, or the environment. These agents can cause disease, but typically do not pose a severe threat to healthy adults, animals, or the environment, and effective preventive and therapeutic measures are available.
• P3 (Protection Level 3): A containment laboratory suitable for handling agents that can cause serious or potentially lethal diseases in humans, animals, plants, or the environment, primarily through direct contact or aerosols. These agents pose a high risk but usually have effective preventive and therapeutic measures available.
• P4 (Protection Level 4): The highest level of containment laboratory, suitable for working with agents that pose a high risk of life-threatening diseases in humans, animals, plants, or the environment. These agents may spread via aerosols or have unknown transmission routes, and no effective preventive or therapeutic measures are available. Examples include the Ebola virus.

Animal Biosafety Levels (ABSL): For laboratories conducting experiments involving live animals, the biosafety levels range from ABSL-1 to ABSL-4.

Laboratory Access Guidelines

• Do not wear shorts, sandals, or loose jewelry in the laboratory. Long hair must be tied back.
• No smoking, eating, or drinking in the laboratory. Ensure the laboratory is clean and free from food or personal items.
• Keep the laboratory tidy and clean workbenches at least once daily. Properly store equipment and manage waste.
• Familiarize emergency procedures, escape routes, and fire safety equipment.
• Do not bring unauthorized personnel into the laboratory.
• Wash hands before leaving the lab. Lab coats and gloves are prohibited in public areas.
• Do not leave the experiment site for long periods while experiments are in progress.
• Abide by regulations and have a good sense of biosafety, and develop good experimental habits.

Chemical Management

• Storage: Store chemicals based on their properties (flammable, explosive, toxic, corrosive, etc.).
• Labeling: Ensure clear labeling of chemical containers with names, hazards, and handling instructions.

Table 1: Common Hazardous Chemicals in Molecular Labs

No.	Reagent Name	Characteristic	Hazard
1	Ethidium Bromide (EB)	Fluorescent dye, simple and fast for nucleic acid detection	Carcinogenic
2	Diethyl Pyrocarbonate (DEPC)	RNAse inhibitor used for reagent preparation	Potential carcinogen
3	Sodium Dodecyl Sulfate (SDS)	Damaging respiratory tract	Eye and respiratory irritant
4	Acrylamide	Used in gel polymerization	Neurotoxin
5	Tetramethylethylenediamine (TEMED)	Seal preservation	Neurotoxin
6	β-Mercaptoethanol	Irritating odor	Harmful to mucous membranes and respiratory tract

Equipment Use

Glassware: Use properly and avoid using damaged glassware. Avoid placing hot glassware on cold surfaces.

Equipment operation: Read and understand operating procedures before use. Inspect equipment regularly to prevent potential hazards.

Table 2: Common Equipment Operation Precautions

No.	Name of Equipment	Matters Needing Attention
1	Forced Air Drying Oven	- Continuous monitoring is required during operation. Do not place flammable paper items inside, and ensure that the oven is not used for extended periods. Overnight operation is strictly prohibited.
2	Biological Safety Cabinet (BSC)	- Before use, ensure the front glass window is closed and turn on the UV light for at least 20 minutes to sterilize. - During operation, turn off the UV light to prevent UV exposure and turn on the fan to disperse ozone. - Disinfect items before placing them inside. Do not use the safety cabinet as storage, as this can interfere with airflow patterns and reduce its protective efficiency.
3	Microwave Oven	- Only use the microwave for heating laboratory reagents. Avoid drying out reagents, and ensure someone is present to monitor the heating process. Never leave it unattended or operate overnight.
4	Needles and Syringes	- As needles are sharp instruments, handle them with extreme care to prevent liquid leakage or accidental contact with the needle, which could cause injury or contamination. - After use, clean the syringes immediately. Destroy used needles and dispose of them according to medical waste disposal regulations to prevent accidental reuse and potential harm.
5	High-Temperature Autoclave	- Overnight operation is prohibited to prevent safety risks associated with long-term exposure to high temperatures and pressure. - After operation, wait for the temperature to drop to a safe range before stopping the equipment to ensure safe handling.
6	Centrifuge	- Before starting, ensure samples are balanced to prevent vibration or imbalance during the centrifugation process. - Operators must not leave the centrifuge unattended during operation to respond to any abnormalities immediately. - Do not open the lid or engage in any other unauthorized operations while the centrifuge is running, to avoid liquid splashing or equipment damage. - The volume of liquid in centrifuge tubes should be controlled (typically about half of the tube's capacity) to avoid spillage during centrifugation.
7	Water Bath	- Overnight operation is prohibited. Ensure the water bath is regularly cleaned and disinfected.
8	Refrigerators and Freezers	- Laboratory refrigerators and freezers do not have explosion-proof devices, so flammable, explosive, or volatile solvents must not be stored inside. - Personal food and non-laboratory items are strictly prohibited to maintain the purity and safety of laboratory materials. - All low-boiling-point reagents stored in refrigerators or freezers must be properly labeled for identification and management. Containers must be tightly sealed to prevent reagent evaporation or contamination. - Regularly clean the refrigerator and remove unnecessary samples and reagents to maintain cleanliness and hygiene inside.

3 Common Basic Laboratory Experiments

Acid-Base Titration

• Clean the apparatus: Ensure that the burette, beaker, and graduated cylinder are clean and free of contaminants.
• Record the initial volume: Before starting the titration, record the initial volume of the solution in the burette.
• Titrate slowly: Add the titrant at a steady and slow pace, especially when approaching the endpoint.
• Observe color change: When using an indicator, carefully watch for the color change to accurately determine the titration endpoint.
• Record the final volume: After completing the titration, record the final volume of the solution in the burette.
• Dispose of waste safely: After titration, properly dispose of the reaction solution and avoid pouring it down the drain.

Heating Experiment

• Check the equipment: Before use, ensure that heating devices such as alcohol lamps or hot plates are in good condition.
• Monitor heating: Never leave the heating process unattended; it must be supervised at all times.
• Use protective gear: Use heat-resistant gloves and safety goggles when necessary.
• Avoid overheating: Prevent containers from directly contacting heating elements to avoid overheating or burning.
• Allow for cooling: After the experiment, let the heating equipment cool down to room temperature before cleaning.

Solution Preparation

• Accurate measurement: Use precise measuring tools such as graduated cylinders or balances to ensure the correct ratio of solute and solvent.
• Order of dissolution: Typically, add the solid to the container first, then pour in the liquid solvent.
• Stir thoroughly: Ensure the solid dissolves completely by stirring to speed up the process.
• Use a fume hood: When handling volatile or irritating chemicals, work inside a fume hood.
• Label the solution: Clearly label the solution with its name, concentration, and preparation date.

Microscope Observation

• Adjust the microscope: Ensure the microscope field is clear and adjust the objective and eyepiece to suitable positions.
• Correct placement of the slide: Place the slide securely on the stage and fix it with clips.
• Gentle focusing: Slowly turn the coarse focus knob until the sample is roughly in focus, then use the fine focus knob for precise adjustments.
• Protect the lenses: Avoid touching the lenses to prevent contamination or damage.
• Proper lighting: Adjust the diaphragm to provide enough light without making it too bright, which could affect observation.

Bacterial Culture

• Aseptic technique: Work under sterile conditions, including sterilizing inoculating loops with flame and minimizing the exposure of culture plates.
• Keep plates clean: Avoid touching the inside of culture plates to prevent contamination.
• Control incubation conditions: Ensure proper temperature and time are provided to promote bacterial growth.
• Observe and record: Regularly check bacterial growth and keep detailed records.
• Waste disposal: After the experiment, properly dispose of culture plates and media according to biohazard waste protocols.

4 Common Laboratory Hazards and Preventive Measures

Electrical Hazard

• Ensure all electrical equipment is properly grounded and inspect wires and plugs for damage before use.
• Avoid operating electrical devices with wet hands, do not overload sockets, and conduct regular maintenance and safety checks.

Chemical Hazard

• Read the instructions before using chemicals, understand the associated hazards, and know how to handle emergencies.
• Properly store and handle chemicals, ensure labels are clear, and be familiar with the properties of each chemical.
• Wear lab coats and protective gear according to safety regulations during chemical handling.

Radiation Hazard

• Wear protective goggles when using UV lamps and avoid direct exposure to the light source.
• Handle radioactive isotopes in designated areas, wear protective clothing, and use a dosimeter.
• Follow strict radiation safety protocols and regularly monitor the radiation levels in the work area.

High-Temperature and High-Pressure Hazard

• Wear protective gloves, face shields, and other protective gear when using high-temperature equipment.
• Regularly inspect and maintain high-pressure vessels, and operate them within the specified temperature and pressure limits. Avoid over-temperature and over-pressure operations.

Freezing and Low-Temperature Hazard

• Wear protective gloves when handling cryogens and avoid direct contact.
• Operate in well-ventilated areas to prevent asphyxiation from cryogen vapors.
• Ensure containers are sealed properly during storage and use to prevent leaks.

Mechanical Hazard

• Inspect mechanical equipment before use to ensure all parts are intact and no components are loose.
• Follow the operational procedures and use mechanical equipment correctly.
• Avoid wearing loose clothing or accessories that could be caught in machinery.

5 Emergency Incident Response

Fire & Explosion

• Alarm: Immediately call the fire department, clearly reporting the fire location, size of the fire, and whether anyone is trapped.
• Using a fire extinguisher: Select the appropriate type of fire extinguisher (e.g., a dry powder extinguisher for oil or electrical fires; a CO2 extinguisher for precision equipment fires). Stand upwind from the fire, pull the safety pin, and aim the nozzle at the base of the flames.
• Evacuation route: Be familiar with the emergency evacuation map and multiple escape routes. Move in a low posture, cover your nose and mouth with a damp cloth, do not use elevators, and evacuate quickly and orderly to a safe area.

Chemical Spill

• Personal protection: Quickly wear protective gear such as a chemical suit, gas mask, and gloves. If no proper protective equipment is available, immediately leave the spill area.
• Control the source: If possible, close the leak source, such as valves or pipes. Use sand, oil-absorbing mats, or similar materials to contain the spilled liquid and prevent further spread.
• Report and clean up: Immediately report the spill to superiors or emergency management. Wait for professionals to handle the situation and avoid attempting cleanup yourself to prevent secondary injuries.

Electric Shock

• Remove the victim from the power source: Immediately cut off the power supply. Use insulated tools to safely remove the victim from the power source, ensuring your safety.
• Check the injured person: After removing the victim from the power source, move them to a ventilated, dry area and lay them flat on their backs. Check their condition immediately.
• First aid and medical help: Administer appropriate first aid depending on the severity of the injury. If the victim’s heartbeat or breathing has stopped, immediately call 911 (or 120 in China) and begin CPR until medical professionals arrive.

6 Laboratory Safety Equipment

Emergency Shower

1. Activate the device: Quickly pull the handle or press the activation button to start the water flow. Some devices are designed with automatic sensors, but most still require manual activation.
2. Rinse the affected area: Direct the injured part of your body under the shower’s water flow for thorough rinsing. Ensure the water runs continuously and strongly to dilute and wash away harmful substances.
3. Flushing time: Rinse the affected area for at least 15 minutes, or until emergency personnel arrive and instruct you to stop. The duration depends on the nature of the spilled chemicals and the severity of the injury.
4. Report and seek help: While rinsing or after rinsing, immediately report the incident to superiors or emergency management, and seek further medical assistance.

Eye Wash

1. Turn on the water flow: Before using the eye wash station, ensure the water flow switch is turned on and the water is running properly. Some eye wash stations are operated by hand push or foot pedals; follow the specific model's instructions.
2. Eye flushing: Position your eyes over the nozzle of the eye wash station and gently open your eyes, allowing the water to thoroughly rinse them. Ensure the water covers the entire eye, and move your eyes in all directions to help flush out harmful substances from the conjunctival sac.
3. Flushing time: Similar to emergency showers, flush your eyes for at least 15 minutes, or until emergency personnel arrive and instruct you to stop.
4. Avoid rubbing: Do not rub your eyes during the flushing process, as this may exacerbate the injury.
5. Follow-up treatment: After flushing, seek immediate medical attention for further examination and treatment.

Firefighting Equipment

Essential emergency rescue equipment should be placed in a visible and easily accessible location. It must be managed and regularly inspected by designated personnel. Laboratory staff should be familiar with the use of firefighting equipment and ensure it is always in good working condition.

7 First Aid

Basic Cardiopulmonary Resuscitation (CPR)

1. Initial assessment: Quickly check the victim’s consciousness and breathing status. If unresponsive and not breathing, immediately activate the emergency response system (e.g., call emergency services).
2. Chest compressions: Check for a pulse. If there is no pulse, begin chest compressions immediately. Compress the chest to a depth of 5-6 cm, at a rate of 100-120 compressions per minute, ensuring effective compressions.
3. Rescue breaths (if applicable): Along with chest compressions, provide rescue breaths at a ratio of 30:2, meaning 30 compressions followed by 2 breaths.
4. Continue CPR: Continue performing CPR until professional medical personnel arrive and take over.

Bleeding Control and Bandaging

1. Direct pressure to stop bleeding: For bleeding wounds, first apply direct pressure to the bleeding site using a clean cloth or bandage.
2. Avoid removing embedded objects: If the wound is large or has embedded objects, do not attempt to remove the objects as this could worsen the injury. Instead, bandage around the object to stop the bleeding.
3. Pressure bandaging: Use a bandage or triangular cloth to apply pressure, ensuring it is tight enough to stop the bleeding but not so tight as to impair circulation.
4. Elevate the injured limb: For limb injuries, elevate the injured area if possible to reduce bleeding and seek medical attention as soon as possible.

8 Waste Disposal

Follow national and local regulations for hazardous waste disposal, ensuring chemical waste is collected and disposed of safely.

Solid Waste

1. Classified collection: Solid waste must be strictly sorted and collected to avoid mixing.
2. Toxic waste treatment: Toxic solid waste must undergo decontamination before disposal to ensure it poses no harm to the environment or human health.
3. Special waste handling: Waste with strong odors or fine particles should be sealed in containers; broken glass and sharp materials should be collected in a sharps container and clearly labeled to prevent accidents.
4. Centralized disposal: All processed solid waste should be stored in a designated area and periodically handed over to qualified professional organizations for disposal.

Liquid Waste

1. Classified storage: Laboratory waste liquids should be stored according to their properties to prevent cross-contamination.
2. No direct discharge: It is strictly prohibited to pour waste liquids directly into the drainage system to avoid water contamination.
3. Decontamination and labeling: Waste liquids must be decontaminated and clearly labeled with their components and hazards.
4. Safe storage and regular collection: Treated waste liquids should be stored in a safe location and regularly collected by professionals for unified disposal.

Gaseous Waste

1. Pre-treatment: Toxic or odorous gases must be treated with absorption, purification, or other pre-treatment measures before being released.
2. Concentration testing: After treatment, gases should be tested to ensure that harmful substance concentrations are below national safety emission standards.
3. Safe discharge: Once the emission standards are met, gases can be safely discharged, ensuring no harm to the atmospheric environment.