What are the material requirements for pharmaceutical equipment used in clean workshops?

    Can 304 stainless steel be used for stainless steel pharmaceutical equipment used in clean workshops? Do parts that come into contact with medicines have to be made of 316L material? Regarding this issue, industry insiders said, "The material depends on the use. If it is just a simple liquid preparation, the material requirements can be looser. But if it is in direct contact with the reactant, using 304 material may not be enough. In addition, the product also needs to be considered quality standards and polymetallic requirements.” The summary can be summarized as follows: 316L equipment is usually used, but there is no mandatory requirement, so it is not necessary to use 316L. The choice is mainly based on the characteristics of the product.

    According to the Good Manufacturing Practice for Pharmaceuticals (2010 revised edition), the document does not mandate that parts of pharmaceutical production equipment that come into contact with materials must use stainless steel 316L or 304. It only requires that production equipment should reduce cross-contamination as much as possible and be corrosion-resistant.

    Article 71 emphasizes: “The design, selection, installation, modification, and maintenance of equipment must conform to the intended purpose, reduce the risk of contamination, cross-contamination, confusion, and errors as much as possible, and be easy to operate, clean and maintain. When necessary, Can be cleaned or sterilized.” In addition, Article 73 mentions: “Production equipment shall not have any adverse effect on the quality of pharmaceuticals. The surfaces of production equipment in direct contact with pharmaceuticals shall be flat, smooth, easy to clean or disinfect, resistant to corrosion, and shall not Chemically react with drugs, adsorb drugs, or release substances.”

    In addition to this specification, some industry experts also mentioned that there is a similar description in the ISPE Baseline Guide solid preparations: Generally, stainless steel that is in direct contact with materials uses 316L or higher grade material, and stainless steel that is not in direct contact with materials uses 304 or higher grade material. Grade materials, such as clean benches, negative pressure weighing rooms, grade 100 laminar flow hoods, and other pharmaceutical-specific purification equipment, can be made of 304 stainless steel to meet pharmaceutical needs.

    So, what is the difference between 316L and 304? According to the data, there are mainly the following differences:

(1) From the naming point of view, 304 is one of the common stainless steel materials with a density of 7.93g/cm³, while 316L is a stainless steel material grade. For example, AISI 316L is an American standard, sus316L is a Japanese standard, and our country’s unified code is S31603;

(2) From the composition point of view, 304 maintains the inherent corrosion resistance of stainless steel, and the steel must contain more than 18% chromium and more than 8% nickel; while 316L is a derivative of 18-8 austenitic stainless steel. Added 2%~3% molybdenum;

(3) From an application perspective, 304 has good processing performance and weldability and is widely used in building materials, the chemical industry, the food industry, agriculture, and other fields, while 316L has stronger corrosion resistance than 304. More resistant to corrosion in high-temperature environments. Therefore, in high-temperature environments, engineers usually choose parts made of 316L material.

    In summary, the above-mentioned specifications and ISPE do not have mandatory requirements for stainless steel materials. For pharmaceutical equipment companies, the choice of materials mainly depends on the actual production conditions of the pharmaceutical company's products. To ensure the quality and safety of drugs, equipment manufacturers where conditions permit should manufacture according to high standards, and high requirements, and select high-quality materials. However, if there are difficulties, companies should also consider all possible risks when lowering design standards, such as rust, etc. Otherwise, it may have irreversible consequences.