AbhilekhSterilization & high temperature · 121 °C · 134 °C · to +1000 °CAutoclave, oven and sterilization cycle monitoring
A sterilization cycle is a claim about lethality delivered to the coldest point of a load. The chamber drain probe cannot prove that — a penetration probe in the load can.
Moist-heat and dry-heat sterilization are validated on the coldest point of the load, not the warmest point of the chamber. A 121 °C cycle for 15 minutes, or a 134 °C cycle for 3 minutes, describes what has to be delivered to that point; what the chamber controller sees at the drain is a related but different number. Dry-heat depyrogenation pushes the same logic higher, to 250 °C and above.
That gap is why independent penetration-probe monitoring exists. Thermocouples are placed in the hardest-to-heat positions of a representative load, the cycle is run, and lethality is calculated from what those probes actually recorded. The instrument has to survive the cycle, keep logging when chamber power cycles, and produce a record that stands up in a validation report.
ABH-300-TC takes Type-K thermocouple input to +1000 °C with battery backup through the cycle, which covers autoclaves, dry-heat ovens, depyrogenation tunnels and sterilization furnaces from one instrument family.
The expectations behind the record
What an inspector or auditor looks for in this use case, and the framework each expectation comes from.
Lethality demonstrated at the coldest point of the load
Heat distribution and heat penetration studies identify the slowest-to-heat position in a representative load, and the cycle is validated on what that position receives — not on the chamber set point.
Independent measurement alongside the chamber controller
The controller that runs the cycle should not be the only evidence that the cycle was delivered. Calibrated independent probes are what make the validation defensible.
Thermocouple calibration traceable and pre/post-checked
Thermocouples drift and get damaged. Traceable calibration before the study and a post-study verification are both expected, with the results in the validation package.
Cycle records under computerised-system controls
Sterilization records support batch release, which makes them GxP records: access-controlled, audit-trailed, and not editable after the fact.
The failure modes nobody budgets for
Every one of these is a real reason monitoring programmes lose their audit trail — or lose the trust of the people who work with them.
Chamber temperature mistaken for load temperature
The drain probe reaches set point long before a wrapped instrument tray or a filled bottle does. Validating on the chamber reading over-states the lethality actually delivered.
Instruments that cannot take the cycle
Saturated steam at 121 °C, or an oven at 250 °C, destroys general-purpose loggers. The sensing element has to be rated well above the process, not at it.
Chamber power cycling mid-run
A logger powered from the equipment loses the end of the cycle — which is precisely the part the lethality calculation depends on.
F₀ calculated by hand, in a spreadsheet, once a year
Manual lethality arithmetic from exported CSVs is slow, hard to review, and the first thing an auditor asks to see recalculated.
Engineered for this, specifically
Each point below maps to a documented platform behaviour — not a marketing promise.
Type-K penetration probes to +1000 °C
ABH-300-TC accepts Type-K thermocouple input (−40 to +1000 °C, Inconel 600 sheath on fibreglass cable) via a MAX31856 converter — headroom for autoclaves, dry-heat ovens and depyrogenation tunnels alike.
Battery backup through the cycle
The instrument keeps logging when the chamber's own power cycles, so the cooling phase and the end of the cycle are on record rather than inferred.
Fast sampling where the gradient is steep
Sampling to one second resolves the come-up and cool-down phases where load and chamber diverge most — the phases that determine the lethality you can claim.
Per-probe calibration tracked, pre and post
Probe channel templates live in the instrument's ID EEPROM, and NIST-traceable certificates, due dates and reminders are tracked per probe, with calibration status carried into every report.
Cycle records in the same audit chain
Every cycle, review and e-signature enters the same SHA-256 chain as your storage and distribution records, with identity, timestamp and meaning of signature captured on each signing.
The ABH loggers for this job
Abhilekh runs its own logger line end to end — one manufacturer owns the chain from probe accuracy to the signed record.
- ▸PRB-TC-K-3M — Type-K penetration probe, Inconel 600 sheath, to +1000 °C
- ▸PRB-TC-K-3M-HT — ceramic variant for sustained high-temperature duty
The ABH line is at the design-frozen, pre-production stage. Every battery-life, drop, thermal and IP figure is a calculated or simulated design estimate, and the regulatory marks referenced on this site are a certification roadmap — not held certificates.
Questions, answered
Other environments we monitor
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