Views:27 Author:Site Editor Publish Time: 2020-09-20 Origin:Site
Wear the necessary protective tools according to the dangerous accidents that may occur in the test, such as wearing a test suit, rubber gloves, protective masks, gas masks, etc. Before the experiment, pay attention to clean up the hidden dangers around the test site. Check whether the test equipment, drugs and related articles are not in compliance with the requirements.
The matching reaction device should be selected according to the nature and process of the chemical reaction, which can save trouble and save necessary safety measures.
Although the experimental accident is unpredictable, the magnitude of its risk can be estimated. Even for experiments that are not well understood, it is necessary to guess the degree of danger and formulate corresponding preventive measures. Experiments like the following must be very careful to make them foolproof.
①Do not understand the reaction and operation;
② Experiments with multiple risks (such as fire, poisonous gas, etc.);
③Experiments carried out under severe reaction conditions (such as high temperature, high pressure, etc.).
Usually pay attention to be familiar with the main faucets, electrical switches that need to be turned off, the location and operation of the fire extinguisher, and to avoid accidents before looking for emergency items.
The post-processing work of the experiment is also an integral part of the experiment process. In particular, do not neglect the treatment of recovered solvents, waste liquids, and waste.
Handling of hazardous substances and precautions
Hazardous substances refer to substances with fire, explosion or poisoning hazards.
1. Before using hazardous substances, fully understand the properties of the substances used, especially the dangers of fire, explosion and poisoning.
2. Storage. Generally, hazardous substances should be protected from sunlight and stored in a cool place. Be careful not to mix in foreign objects. And must be separated from fire or heat sources. Precautions for the use of laboratory refrigerators and ultra-low temperature refrigerators: defrost and clean regularly, and disinfect the inner surface after cleaning; all storage containers should be marked with the name of the item, the storage date and the name of the store; unless there are explosion-proof measures, otherwise the refrigerator Do not place flammable and explosive chemical solutions, which should be marked on the refrigerator door.
3. Before using dangerous substances, the protective measures in the event of a disaster must be considered in advance and careful preparations must be made. When using substances with fire or explosion hazards, prepare protective masks, heat-resistant protective clothing, and fire-extinguishing equipment; for toxic substances, prepare rubber gloves, gas masks, and protective clothing.
4. When possible, use as little or no hazardous substances as possible. In addition, preliminary tests are required for substances whose performance is not known.
5. For toxic drugs and wastes containing toxic substances, appropriate treatment should be carried out after use to avoid pollution of water and atmosphere.
There are many substances with fire hazard. Generally, there are substances that catch fire due to heating and impact, and some substances that catch fire due to contact or mixing. Such as strong oxidizing substances, strong acid substances, low-temperature ignitable substances, natural substances, water-proof substances, etc.
The danger of combustibles can be roughly judged based on their ignition point. The lower the ignition point, the greater the risk. However, even a substance with a high ignition point is dangerous when heated to a temperature above its ignition point. According to reports, there have been many accidents due to this situation. Therefore, attention must be paid.
There are two kinds of explosions: one is that flammable gas mixes with air, and when it reaches its explosive limit concentration, it catches fire and burns and explodes; the other is that easily decomposed substances decompose due to heating or impact, resulting in a sudden gasification decomposition explosion.