Three indicators for pure steam quality testing

• Non condensable gas content (NCG)Non condensable gases such as air and CO ₂ can reduce steam heat transfer efficiency and affect sterilization effectiveness. According to the EN285 standard, the non condensable gas content should be ≤ 3.5%, while the pharmaceutical industry typically requires ≤ 2.5%. Suzhou Yikang Environmental Testing may use cooling method (measuring residual gas volume after condensing steam) or temperature difference method (calculating the difference between steam and saturation temperature) for testing.

• Dryness Value (DV)Dryness refers to the ratio of gas phase (dry steam) to liquid phase (liquid water) in steam, and the ideal dryness of pure steam should be ≥ 95%. If the steam drying degree is insufficient, it will hinder heat transfer, causing moisture load on porous materials for sterilization, and uneven temperature distribution for non porous materials for sterilization. Suzhou Yikang may use a steam separator to collect liquid water and calculate dryness, or calculate by measuring the thermodynamic state of steam.

• Superheat (SH)Overheating refers to the degree to which the steam temperature exceeds its saturation temperature. Excessive overheating can lead to sterilization failure and may also accelerate the aging of rubber products. According to the EN285 standard, the degree of superheat should be ≤ 25 ℃, but the pharmaceutical industry typically requires ≤ 5 ℃. The detection method is generally the direct temperature measurement method, which measures the steam temperature and compares it with the saturation temperature

Three indicators for pure steam quality testing