F-value Computation for the Sterilization Process for Pharmaceutical and Chemical Products


When sterilizing preserved foods by heating, bacteria must be completely annihilated without changing the heat of the product (a degradation of the taste) and the integrated fatality (F value) must be recorded and monitored. By using the computation function of the SMARTDAC+ series Paperless recorder GX/GP (relational computation, four arithmetical operations, and exponential computation), the F value can be calculated and recorded.

Setting example


  • The F value at a specified sterilization temperature is automatically computed and recorded as production data.
  • Using external input contact, recording can be started or stopped automatically.
  • Automatic data file transfer and WEB monitoring are available.

F value

“F value” is The integrated fatality of the bacteria obtained by heat sterilization.  It is the integrated value of the fatality rate (Li) of the bacteria per unit amount of time (Δt),  and Li is a function of the sterilization temperature.

F value computation


Configuration Example on the SMARTDAC+

Ex. Sterilization temp. Tr=121.1degC, Z value Z=10degC,
      Measurement interval Δt=0.0167min(=1sec)

  • Constant
    K1=10, K02=10.0degC(Z value), K03=121.1degC(Sterilization temp.), K04=0.0167min(measurement Interval), K05=100degC(measurement interval)
  • Constant K2 to K5 may vary depending on the conditions.
  • Equations
    Measurement channel 0001
    MATH channel A001: K01**((0001-K03)/K02) ←Li value
    MATH channel A002:(A002+A001*K04)*(0001.GT.K05) ←F value

*When the temperature falls to 100℃, the value of A002 is reset to 0.

Temperature monitoring for HACCP

In HACCP, the temp. management is required for the whole food supply chain (ex. Food manufacturing, processing, cooking, and sales). SMARTDAC+ series can record multiple points of temp. in production lines, facilities or environment of storage …etc.
It provides strong supports for your temp. management.

Temperature monitoring for HACCP


Related Products & Solutions

Button Operated DX1000/DX2000

The Daqstation DX1000/2000 series is a data acquisition system with display. Its HMI supports custom graphics for industry applications, audit trail and advanced security conforming to FDA 21CFR Part 11.

Touch Screen GX10/GX20

SMARTDAC+ GX10/GX20 is a multi-point touch screen recorder that provides intuitive, human-centric design, web-enabled functionality, and scalable architecture. The GX20 also supports 920 MHz band wireless communication.

µR10000 & µR20000

The μR series are the compact industrial recorders with the recording widths of 100 mm (μR10000) and 180 mm (μR20000).


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