Dew point requirement of compressed air for pharmaceutical industry

In the pharmaceutical industry, the dew point requirements for compressed air are extremely stringent, generally, it should be controlled below -40 ℃ some high-risk scenarios even require -70°C (ISO8573-1 Class1) to ensure the safety of the drug production environment and the stability of product quality. The following analysis is carried out from the three dimensions of standard basis, industry practice and risk control:

1. Standard Basis: International and Domestic Double Norms

1. international Standards (ISO8573-1)
   • Class 1: Compressed air in direct contact with drugs shall meet dew point ≤-70 ℃ (pressure dew point), and solid particles (particle size ≤ 0.1 μm, concentration ≤ 0.1/m & sup3;) and oil content (≤ 0.001 mg/m & sup3;) must reach the highest cleanliness level.
   • Class 2: The dew point requirement of compressed air in indirect contact (such as power drive) is relaxed to ≤-40 ℃, and the oil content is ≤ 0.01 mg/m & sup3;.
   • The standard provides precise guidance for different application scenarios through a grading system to avoid energy waste and equipment damage.
2. Domestic Standards (GB/T 13277.1-2023)
   • the dew point temperature is divided into 6 levels, where level 2 standard (dew point ≤-40 ℃) it is clearly applicable to pharmaceutical shops and corresponds to ISO8573-1 Class 2.
   • The standard emphasizes that "the lower the dew point temperature, the drier the air", and requires enterprises to select the appropriate level according to the production process, for example, pneumatic tools need to meet level 3 (dew point ≤-20 ℃), while the basic compressed air supply only needs level 6 (dew point ≤ 10 ℃).

2. industry practice: dew point control and process safety deep binding

1. extreme requirements for direct contact scenarios
   • in the production of sterile preparations, compressed air needs to be filtered through terminal sterile filtration, but the dew point must be ≤-70 ℃(ISO8573-1 Class 1) before filtration to prevent microbial growth. For example, if the water content of compressed air exceeds the standard in the injection filling process, it may lead to liquid pollution and cause serious quality accidents.
   • A case of a pharmaceutical company: its aseptic workshop adopts an adsorption dryer to stably control the dew point at -75 ℃ and cooperate with a 0.01μm precision filter to ensure zero risk when compressed air directly contacts drugs.
2. Balancing strategies for indirect contact scenarios
   • for indirect contact scenarios such as power drive and pneumatic control, dew point control at -40 ℃ can meet the demand. For example, if the compressed air used in the tablet press has a high dew point, it may cause equipment corrosion, but -40°C can already avoid the formation of condensation water.
   • Cost optimization: Through risk assessment, an enterprise relaxed the dew point standard of non-critical areas (such as packaging lines) from -40 ℃ to -20 ℃, saving the energy consumption cost of the dryer by about 200000 yuan per year.

3. risk control: the whole chain management from equipment selection to dynamic monitoring

1. equipment selection and system design
   • dryer Configuration: Pharmaceutical companies generally use the "freeze dryer adsorption dryer" combination, the former will reduce the dew point to 3 ℃, the latter further down to -40 ℃ or -70 ℃, to ensure that the export pressure dew point fluctuations ≤ ± 2 ℃.
   • Pipe material parts in contact with compressed air (such as cylinders, pipes) need to use 316L stainless steel, the inner wall electrolytic polishing (Ra≤ 0.8 μm), to avoid microbial adsorption and corrosion.
2. dynamic monitoring and verification
   • online detection A capacitive dew point sensor is installed behind the compressed air preparation system and at the most remote use point of each use floor to monitor data in real time and link alarm.
   • Periodic verification: The newly installed system shall be tested every 3 months, and the mature system shall be tested every 6 months to 1 year. The test items include dew point, oil content, dust particles and microbial limit (the direct contact scene shall be ≤ 1CFU/m & sup3;).
   • Record Traceability establish an electronic ledger, record test data, maintain records and corrective measures to ensure compliance with GMP requirements.

Consequences and Rectification Cases of Excessive 4.

1. Quality risk
   • excessive dew point may lead to high water content in compressed air, causing moisture, equipment corrosion or microbial contamination. For example, the dew point of an enterprise rose to -10 ℃ due to the failure of the dryer, resulting in visible foreign matter in a batch of injections, resulting in a direct loss of more than 5 million yuan.
2. Rectification measures
   • filter Element Replacement: If the oil content is found to exceed the standard (such as 0.005 mg/m & sup3;), the high-efficiency oil and gas separator or activated carbon filter should be replaced immediately, and the replacement cycle should be shortened.
   • pipeline reconstruction: Eliminate blind pipes (≥ 3D) formed by right-angle elbows, switch to 45 ° elbows and increase drainage points to avoid accumulation of condensed water.
   • System Upgrade: Technical transformation of the old dryer, such as adding heating regeneration function, raising the dew point from -20 ℃ to -40 ℃.