1、 Laboratory environment and equipment requirements

1. Ventilation facilities: The laboratory should be equipped with excellent ventilation facilities to ensure air circulation and timely discharge of harmful gases that may be generated, such as exhaust gas from acetylene combustion.

2. Fire prevention signs and equipment: The laboratory should be equipped with clear safety signs, sufficient fire alarm devices and firefighting equipment, and regularly inspected and maintained.

3. Emergency stop button: An emergency stop button should be installed in the work area to quickly stop the operation of the instrument in case of emergency.

4. Personal protective equipment: Operators must wear personal protective equipment that complies with laboratory safety regulations, such as laboratory coats, gloves, goggles, etc. For operations involving toxic substances, personal protection should be strengthened.

2、 Preparation and inspection before operating atomic absorption spectrophotometer instrument

1. Comprehensive inspection: Before operation, a comprehensive inspection of the absorption spectrophotometer is required to ensure that all components are functioning properly, undamaged, and securely connected.

2. Cleaning the instrument: Ensure that the instrument is clean, and promptly clean any stains to avoid affecting the experimental results and instrument performance.

3. Turn on the ventilation system: Turn on the laboratory ventilation system to ensure indoor air circulation and provide a safe environment for the experiment.

3、 Gas usage and safe operation of atomic absorption spectrophotometer

1. Acetylene cylinder management:

Acetylene steel cylinders should be placed in a room adjacent to the instrument room, with air circulation maintained and fire safety signs.

The outlet pressure of acetylene pressure reducing valve should be controlled at around 0.07MPa, not exceeding 0.1MPa, and the air outlet pressure should be between 0.25-0.3MPa. Be careful not to use oxygen instead of air for ignition experiments.

When the pressure displayed on the steel cylinder is below 0.3MPa, a new cylinder should be replaced to ensure the stability and safety of gas supply.

It is strictly prohibited to store open flames or excessively hot objects near the acetylene gas source, and the acetylene gas source should not be stored together with oxidizing gas sources.

2. Leakage inspection:

Before each ignition, check whether the waste liquid pipe is properly sealed with water. Only after confirming that the water seal is correct can the ignition be turned on.

Insert the air pipe of the air compressor into the gas pipeline and apply soapy water to check if there is any air leakage at the joints of the gas pipeline. Special attention should be paid to checking whether the explosion-proof plug at the rear of the atomizer is sealed properly, and ignition operation should not be carried out in case of air leakage, otherwise it is prone to backfire and explosion.

3. Ignition and shutdown sequence:

When igniting, turn on the air first and then turn on the acetylene. When extinguishing, turn off the acetylene first and then turn off the air.

After ignition, the operator must not leave and should closely monitor the operation status of the instrument.

When the instrument is not in use on the same day, please burn off the remaining gas in the acetylene pipeline, that is, directly turn off the acetylene main switch and then turn off the air.

4、 Sample processing and storage of atomic absorption spectrophotometer

1. Sample processing: When processing samples, experimental procedures should be followed, such as precise weighing, dissolution, dilution, etc. For toxic or flammable substances, additional protective measures should be taken to prevent contact and leakage of harmful substances.

2. Sample storage: The residue and waste of the analyzed sample should be properly disposed of in accordance with laboratory waste management regulations. Toxic substances and hazardous chemicals need to be stored separately and clearly labeled to prevent cross contamination and accidents.

5、 Instrument operation and maintenance

1. Operating procedures: Instrument settings should follow the operating manual and parameters should not be adjusted without authorization. During the experimental process, suitable working conditions should be selected according to the requirements and kept stable.

2. Regular maintenance: Absorption spectrophotometer is a precision equipment, and regular maintenance is crucial for the normal operation of the instrument and the accuracy of analysis results. Regular maintenance work such as cleaning, lubrication, and calibration should be carried out according to the operation manual.

3. Prohibited live plugging and unplugging: It is strictly prohibited to plug and unplug data cables with power on to prevent damage to the instrument or electric shock accidents.