Safety requirements for the disposal of experimental waste during the operation of fume hoods

Requirements for classified collection

By nature: There are various types of experimental waste with different properties, and they need to be classified according to their chemical properties. For instance, acidic waste (such as hydrochloric acid and sulfuric acid solutions) should be collected separately from alkaline waste (such as sodium hydroxide solution), as the mixture of acids and bases can cause violent reactions, which may generate heat, gas and even lead to explosions. At the same time, organic waste (such as ethanol, benzene and other organic solvents) should be separated from inorganic waste (such as metal salt solutions) to prevent dangerous interactions between substances of different properties.

Distinguish the level of danger: For highly hazardous waste, such as highly toxic chemicals (cyanide solutions), flammable and explosive substances (nitro compound solutions), etc., they should be collected separately and clearly labeled. If these wastes are not properly disposed of, they will cause serious harm to human health and the environment. As for general waste, such as low-concentration salt solutions, etc., they can be collected according to the conventional classification.

Avoid mixing in foreign objects: When collecting experimental waste, make sure that the container only contains the waste generated by the experiment and avoid mixing in other foreign objects such as household garbage and paper. The mixture of debris may affect the subsequent processing of waste. For instance, combustible materials such as paper may increase the risk of waste combustion and interfere with the safe processing procedures.

Container selection and usage requirements

Select appropriate containers: Choose suitable collection containers based on the nature of the waste. For corrosive waste, corrosion-resistant containers should be selected, such as polyethylene, polypropylene and other plastic containers or glass containers (it is necessary to ensure that the glass containers are undamaged and can withstand the corrosion of the waste). For flammable waste, fireproof and explosion-proof containers should be used, such as metal containers (grounding treatment should be done well to prevent static electricity accumulation from causing fires).

Ensure container sealing: The containers used for collecting waste must be well sealed to prevent the waste from volatilizing and leaking. For example, use containers with sealed LIDS and check the sealing after the LIDS are tightly closed. For volatile organic waste, poor sealing can cause it to volatilize into the air, not only polluting the environment but also possibly forming explosive mixtures, increasing the risk of fire and explosion.

Clearly mark the information: Clearly mark the name, composition, hazardous characteristics, generation date and other information of the waste on the container. This is helpful for subsequent processing personnel to understand the nature of the waste and take the correct processing measures. For instance, marking "Concentrated sulfuric acid solution, highly corrosive, produced on XTH, XTH, 2024" makes it clear at a glance for the handling personnel.

Temporary storage requirements

Designated temporary storage area: A dedicated temporary storage area for experimental waste should be set up near the fume hood. This area should maintain a safe distance from the experimental operation area, the storage area for flammable and explosive items, etc. The temporary storage area should have good ventilation to prevent the evaporation and accumulation of waste. For example, set up the temporary storage area in a well-ventilated corner and install ventilation equipment.

Classified storage: Within the temporary storage area, waste should be stored according to its classification. Waste of different natures must not be mixed. At the same time, hazardous waste should be placed in dedicated cabinets or areas and locked for management to prevent unauthorized personnel from coming into contact. For example, store highly toxic waste in locked safes to ensure its safety.

Control storage time: Experimental waste should not be stored for a long time in the temporary storage area. It should be transferred to a professional treatment institution as soon as possible for processing. Storing for too long may increase the risks of chemical reactions and leakage of waste. Generally speaking, the temporary storage period of hazardous waste should not exceed the prescribed period. The specific period can be determined in accordance with relevant regulations and laboratory rules.

Transfer and processing requirements

Follow the prescribed procedures: The transfer and disposal of experimental waste must comply with relevant national and local laws, regulations and provisions. The laboratory should sign a contract with a qualified waste treatment agency, and the transfer and treatment should be carried out by professionals. During the transfer process, a detailed transfer manifest should be filled out, recording information such as the type, quantity, and transfer time of the waste.

Pay attention to transportation safety: During the process of transferring waste from the laboratory to the treatment facility, ensure transportation safety. Transport vehicles should comply with relevant safety standards and be equipped with necessary fire-fighting equipment and emergency response facilities. Transport personnel should undergo professional training to understand the hazardous characteristics of waste and emergency handling methods. For instance, when transporting flammable waste, it is necessary to prevent the vehicle from being hit or rubbed to avoid causing fires.

Supervise the handling process: The laboratory should pay attention to the handling process of waste and ensure that the handling institutions handle it in accordance with the prescribed methods. For some special types of waste, such as those containing radioactive substances, it is necessary to ensure that the treatment institutions have the corresponding treatment qualifications and capabilities to prevent harm to the environment and human health.