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How to determine whether a clean room reaches the planned level?

A "dust fall test" is the standard method to determine whether a clean room meets the planning grade.The table above provides a number of reference particle size concentrations.However, it is not necessary for each particle size to be taken into consideration to determine the grade of clean room.Those particle sizes need to be considered depending on the product being produced in the plant (the manufacturer should be aware of the demand environment in which his product is produced).In this regard, the ISO particle size selection specification, only the size of the selected particles need to be more than 1.5 times the difference.

For example:

Suppose there is a western medicine factory today to build a clean room plant.The PIC/S GMP(EU GMP) specification specifies the size of 0.5μm and 5.0μm to be considered if the manufacturer wishes to apply for GMP certification.Therefore, the particle concentration of 0.5μm and 5.0μm is taken as the basis for the classification of clean room.(It should be noted that the current ISO standard for PIC/S is the 1999 version, not the latest 2015 version.)

If the application for certification is cGMP.Usually a Chinese medicine factory or a medical material factory.According to the specification, only 0.5 μm can be considered.CGMP is usually used in cosmetic and food factories when clean rooms are needed.

Some people are based on the product characteristics, choose to 0.1μm, 0.3μm size of particles as the basis for consideration.The difference between 0.1 and 0.3 is more than 1.5 times in accordance with the ISO standard, so this option is acceptable.0.1 or 0.3 μm is usually chosen for very fine particles that will affect the yield of the product, such as in a wafer plant.

If you do not know the clean room environment of their products, the size of the choice.The reference particle size of 0.5 μm can be selected, which is also the characteristic particle size based on which Fed 209 named the clean room.

In addition to concentration, a very important factor in clean room grading is the status of clean room grading when it is accurate: As built, At rest and Operational.Because different operating conditions will also have an impact on dust fall concentration.

These three states are defined by ISO as follows:

Completion -- The clean room and its facilities are completed and operational, but the equipment, furniture, raw materials and personnel have not been entered.

Shut down -- The clean room and its facilities have been completed and are operational, and the equipment has been installed and operated in a state agreed by the owner and the manufacturer, but there is no operator on site.

In operation -- The state in which the equipment in the clean room is operating under the specified operating procedures and is operated by personnel.