How to protect the body's first line of defense - the skin

As the body's first line of defense, the skin plays an important role in preventing chemical hazards. There are 54 kinds of chemical burns, mainly inorganic acids and inorganic alkalis. Except for illegal operations and equipment accidents, chemical burns are mainly caused by improper personal protection. In addition, many organic solvents, such as carbon tetrachloride, aniline, nitrobenzene, trichloroethylene, leaded gasoline, organic phosphorus, etc., can cause systemic poisoning through absorption of intact skin by the body, even without skin burns.

1. The necessity of wearing chemical protective clothing
In the hot summer or hot work place, due to the expansion of the skin's capillaries, this absorption will accelerate and the incidence will increase. There are also many chemicals such as dyes, rubber additives, pharmaceutical intermediates, etc. that can cause contact and allergic dermatitis. Therefore, people exposed to chemicals must have the concept of "sickness from the skin." Appropriate chemical protective clothing can effectively block inorganic acids, alkalis, solvents and other harmful chemicals, so that it can not be in contact with the skin. As far as chemical plants are concerned, although chemical materials are generally closed in pipelines and reaction tanks, they should also be equipped with appropriate protective clothing for those who are more likely to come into contact with chemical substances, such as feeders and maintenance workers. Operational mistakes or leaks can protect the personal safety of operators to the maximum extent and minimize accidents at work.

2. How to choose chemical protective clothing
Wearing protective clothing is so important to avoid personal injury, so whenever there is a possibility of exposure to dangerous goods, it naturally involves the question: How to provide staff with suitable protective clothing to achieve effective protection requirements? The following describes the basic principles and selection basis for choosing protective clothing.

There are two main types of protective clothing on the market today: limited use of protective clothing and reusable protective clothing. The former does not need to be cleaned after being contaminated in the polluted environment and treated as dirt; the latter can be used repeatedly, and therefore must be cleaned after being contaminated in order to be used again. There is no doubt that disposable work clothes have many advantages over reusable work clothes, such as no decontamination, light weight, relatively low cost, and significant hygienic properties. In particular, for difficult physical labor in contaminated areas, it is generally not recommended to reuse the same suit because excessive perspiration may result in the proliferation of bacteria (bacteria, mold, etc.). Moreover, the cleaning and preservation of reusable work clothes is a complicated, time-consuming and costly task: First, it is not easy to completely clean the contaminants on protective clothing for reuse; After pollution, it is difficult to determine the protective performance of the protective clothing before it can be kept clean. Therefore, from the perspective of safety and cost savings, developed countries have begun to use a limited number of protective clothing.

The most important and basic factor to consider in the protective clothing itself is protective. First, the materials chosen for protective clothing must have protective functions against the corresponding dangerous goods. Manufacturers/suppliers should be able to provide relevant penetration data, and the user can then determine the time of safe wearing based on the time of the specific dangerous goods. Second, the quality of protective clothing also indirectly determines the protective and durable protective clothing. The relevant specifications include sutures, size, quality control and assurance. The size of protective clothing should ensure the fit of work clothes, otherwise it is easy to be snagged by surrounding objects when it is too large, and tearing when it is too small is not only dangerous but also extremely uncomfortable.

Ideal chemical protective clothing requires protection, durability and comfort. If the wearing of protective clothing makes people feel depressed, even if they are equipped with protective clothing, workers may refuse to wear because they are not comfortable enough. Usually the protective clothing with good comfort may not have sufficient protection, such as the traditional woven material work clothes; and the protective clothing with good protection is often very heavy, such as traditional rubber and PVC protective clothing.

3. Protective principle of chemical protective clothing
Chemicals are liquid, gaseous and solid. Chemicals penetrate clothing (protective clothing) in two ways: penetration and penetration. Penetration refers to the process of chemicals passing through the gaps of clothes from the outside to the inner surface. It is a physical process. Penetration is a chemical process. Chemicals are first absorbed from the outer surface of the fabric, and then they reach the inner surface of the fabric through molecular motion. Finally, it is resolved from the inner surface of the fabric. The protection of chemicals mainly refers to two parameters, namely the penetration time and the penetration rate. Infiltration is a slow process. The rate of infiltration begins at a very low rate, then gradually increases and eventually reaches equilibrium. For the determination of the standard penetration time, the European standard is a penetration rate of 1.0 μg/cm2.min. Standard penetration time is an important reference for safe wear time.

During the actual wearing of the protective suit, the infiltration process begins when the protective suit is exposed to a large quantity of chemical liquid. With the extension of wear time of protective clothing, the penetration rate has gradually increased, but for protective clothing that is worn repeatedly, we cannot accumulate the time when it comes into contact with chemicals, nor can we determine the level of penetration rate of chemicals at the time of wear. It is therefore impossible to determine whether the protective suit can still provide effective protection. Moreover, the protective tests on clothing are destructive, and their protection is determined. This protective suit can no longer be worn. Therefore, in order to provide safer and more effective protection, developed countries have now introduced "limited use of protective clothing," which has detailed test data as support, and can be disposed of after use. In this way, not only the price of each piece of protective clothing can be significantly lower than that of reusable protective clothing, which not only reduces costs but also ensures the safety and effectiveness of protection. Therefore, not wearing chemical protective clothing will surely be able to obtain truly effective protection. The protective clothing is not professional, or the level of protection is not enough, or protective clothing may cause ineffective protection due to long-term use. Working in an environment exposed to the possibility of hazardous chemicals poisoning requires proper professional chemical protection suits for effective protection.

When health and even life are at stake, cost and cost are no longer the main factors that affect the decision. However, in the choice of protective clothing should also consider the actual situation to determine the appropriate level of protection products, of course, protective clothing, the higher the level of protection, the higher the price, so if the actual situation does not necessarily require a high level of protection, then It will cause a waste of costs. In short, when selecting protective clothing, relevant risk analysis should be carried out. For example, what kinds of dangerous goods (types) the workers will be exposed to, how dangerous these dangerous goods are to health, how they are concentrated, and in what form (Gaseous, Solid, Liquid) How the worker may come into contact with such dangerous goods (continuously, accidentally). According to the above analysis, the type of protective clothing and the level of protection shall be determined. Comprehensive consideration shall be given to protection, durability, and comfort. And cost factors, choose the appropriate protective clothing.

China Labor Insurance Network