When it comes to moisture-sensitive items, steam sterilization is not appropriate and may damage the accessories contacting drug products. Fh value is used in dry heat sterilization as a heat penetration factor.
Where,
Fh Value = Heat Penetration Factor
Δt = Sterilization Hold Time in Minutes
T = Average Temperature of all probes during a sterile hold in °C
z = Temperature Coefficient in °C
For steam sterilization, the term right to “T” was 121.1°C whereas, in dry heat sterilization, it is 170°C.
Difference between F0 and Fh Value
• The assumed z-value for F0 is 10°C for sterilization range of 100 to 130°C
• The assumed z-value for Fh is 20°C for sterilization range of 160 to 200°C
• Theoretical Requirement for F0 is 121.1°C at 30 min. of sterile hold time
• Theoretical Requirement Fh is 170°C at 32 min. of sterile hold time
Related: F0 Value Calculation in Steam Sterilization
Post a Comment