In 1990, the American Fire Protection Association (NFPA) and the American information and Testing Association (ASTM) proposed and carried out additional specifications, which were recognized by OSHA. The functional requirements of airtight protective clothing are put forward in NFPA 1991. These requirements include chemical and flame resistance tests, which can prevent 21 kinds of essential chemicals.
The United States Environmental Agency (EPA) has designated the work safety and cleaning Administration (OSHA) to provide health and safety maintenance for workers who are in danger of damage data and pollution. OSHA clearly reflects the safety regulations of all environments, and these safety regulations clearly define the operation specifications of all OSHA programs.
Level A--表明最大的風險程度，它對人的呼吸、眼睛或皮膚造成損傷， 這些損傷可能來自有毒蒸氣、氣體、微粒、化學飛濺、沉溺或觸摸有毒資料。 它要求全關閉化學防護服，這種防護服有必要帶SCBA或管路式呼吸器和恰當的附件。Level A化學防護服也可做成契合NFPA1991 規範。
Level B 表明環境要求最高的呼吸維護，但對皮膚維護的要求不高。
The basic OSHA specification requires four levels of maintenance: Level A, B, C, D. workers at each risk level must be equipped with corresponding level of protective equipment and protective clothing to fully maintain users.
Level a - indicates the maximum level of risk, which may cause damage to the person's breath, eyes or skin, which may come from toxic vapor, gas, particles, chemical spatter, addiction or touching toxic information. It requires full closure of chemical protective clothing, which is necessary with SCBA or line respirator and appropriate accessories. Level a chemical protective clothing can also be made to comply with NFPA 1991.
Level B indicates that the environment requires the highest respiratory maintenance, but the requirement for skin maintenance is not high.
It requires SCBA or positive pressure pipeline respirator with escape gas bottle, and protective clothing (one-piece and long sleeve jacket; one-piece, one or two pieces of anti splash chemical protective clothing; or one-piece chemical protective clothing that can be used alone).
In addition, it can meet the future European specification of chemical protective clothing
Class I: air tight protective clothing
The second category: non airtight protective clothing
The third category: liquid fine type protective clothing
The fourth category: spray fine protective clothing.
Category 5: fine dust protective clothing
Class 6: limited spray fine protective clothing
1. Protective fabric
It is very important to select the chemical protective clothing correctly and understand the penetration or penetration of various chemicals.
The penetration test detects the passage of gases, liquids and solids through holes or openings in another solid substance. The penetration test is used to test whether the fabric can leak and block particles or chemicals. When a chemical is absorbed, it saturates on one side of the fabric, then releases the absorbent or diffuses to the other side of the fabric, which is called soaking. It is not necessary to have small holes or openings on the surface of the fabric when it is saturated. The penetration test is very important for fabrics exposed to harmful liquids, vapors and gases.
For those who deal with emergencies, high visibility has its advantages and disadvantages. For example, in a risk environment, it is important that the person dealing with the emergency can be seen by others, while the emergency of hazardous substances will not occur in the appropriate environment. It is an important feature that the chemical protective clothing has high visibility. In addition, there are also situations where the risk of being found to be the same as touching chemical or biochemical preparations due to its high degree of exposure.
3. Stitch structure
Without strong and tight seams, the best fabrics in the world are useless. A loose thread, a gap, will remove the barrier between you and the environment, putting you at risk.
4. Types of protective clothing
Different types or equipment of protective clothing for different operations, which is just like the reason why we supply many kinds of protective clothing, from headgear, vest to apron, one-piece suit and fully closed protective clothing (Grade B and a). There are two kinds of full closed protective clothing: front inlet and rear inlet. There are not only respirators with flat back for external air source, but also protective clothing with protruding back matched with SCBA.
5. Structure of protective clothing
Fully closed protective clothing has many parts and options. Different conditions require different types of masks.