Clean room ventilation frequency standard

(I) In the Clean room standards of various countries, the empirical ventilation times of non-unidirectional clean rooms of the same level are not the same. China's "Cleanroom design Code" (GB 50073-2001) clearly stipulates the empirical ventilation times required for calculating the clean air supply of non-unidirectional clean rooms of different levels, see the table below:

Remarks:

• The ventilation times are applicable to clean rooms with a floor height of less than 4.0m

• When there are few people in the room and the heat source is small, the lower limit value should be adopted.

• The ventilation times of clean rooms greater than 100000 levels shall not be less than 12 times: In addition:

National Standard for Laboratory Animal Environment and Facilities GB 14925-2001 stipulates

Ordinary environment 8~10 times/h

Barrier environment 10~20

High-rise environment 20~50

(II) Temperature and Relative humidity

The temperature and relative humidity of the clean room (area) should be compatible with the pharmaceutical production process. If there are no special requirements, the temperature should be controlled at 18~26℃ and the relative humidity should be controlled at 45%~65%.

(III) Pressure difference

• Clean rooms must maintain a certain positive pressure, which can be achieved by making the air supply volume greater than the exhaust volume, and there should be a device to indicate the pressure difference.

• The static pressure difference between adjacent rooms with different air cleanliness levels should be greater than 5Pa, and the static pressure difference between the clean room (area) and the outdoor atmosphere should be greater than 10Pa, and there should be a device to indicate the pressure difference.

• In the process of producing a large amount of dust, toxic substances, flammable and explosive substances, and the production of strong allergenic drugs such as chloramine, certain steroid drugs, and any production process of microorganisms believed to have pathogenic effects, the operating room and its adjacent rooms or areas should maintain a relative negative pressure.

(IV) Fresh Air volume

A certain amount of fresh air should be maintained in the clean room, and its value should be the maximum value of the following air volumes:

• 10%~30% of the total air supply volume of non-unidirectional clean rooms, and 2%~4% of the total air supply volume of unidirectional clean rooms;

• The amount of fresh air required to compensate for indoor exhaust and maintain positive pressure:

• Ensure that the indoor fresh air volume per person per hour is not less than 40 m3.

(V) Other standard descriptions:

• Sterile Medical Device Management Specifications (VY 0033-2000): Ventilation frequency of 100,000-level clean areas: >15 times/h Ventilation frequency of 10,000-level clean areas: >20 times/h.

• Implementation details of in vitro diagnostic reagents: No specific regulations, only the pressure difference range is specified.

• Pharmaceutical production quality management specifications: No regulations, only the pressure difference range is specified.

• Cleanroom Design Specification (GB50073-2001): Ventilation frequency of 100,000-class clean area: 10 times-15 times/h Ventilation frequency of 10,000-class clean area: 15 times/h-25 times/h. 5GMP Verification Guide (2000 Edition) Recommendation: Ventilation frequency of 100,000-class clean area: >15 times Ventilation frequency of 10,000-class clean area: >25 times/h, Text 6. Biological Contamination Control (1S014644) International Standard Chapter 1 Clean Level Division: Ventilation frequency of 100,000-class clean area: 10 times/-15 times Ventilation frequency of 10,000-class clean area: 15 times/h-25 times/h. In other words, the issue of ventilation frequency can be discussed.