When using glass test tubes in a laboratory setting, it is essential to strictly adhere to a series of key procedures and safety precautions. First and foremost, before and after use, ensure that the test tube is clean and free of residue by thoroughly washing it with detergent, water, or alcohol; additionally, meticulously inspect the tube for any cracks or defects to prevent experimental failure or safety hazards. Furthermore, the test tube must be kept dry, both inside and out, to avoid moisture interference with experimental results. During operations, heating should be conducted gradually to prevent rapid temperature increases that could cause the tube to shatter; similarly, when shaking the tube, handle it gently to avoid splashing the liquid contents.
Moreover, test tubes should be protected from impact with hard objects. When transferring liquids, exercise caution by tilting the tube to prevent spillage, and strictly guard against cross-contamination. For storage, test tubes should be placed securely to avoid accidental collision and clearly labeled to prevent mix-ups. Test tubes containing gases require the stopper to be slightly loosened to prevent breakage caused by pressure fluctuations; additionally, for long-term storage, they should be capped to protect against dust and ensure the continued cleanliness of both the interior and exterior surfaces. Adhering to these professional guidelines will significantly enhance both the safety and accuracy of laboratory experiments.