Calibration and validation are often used as if they mean the same thing. They do not, and an inspector will expect both.

Calibration: is the measurement correct?

Calibration compares a sensor against a traceable reference standard under stable conditions, records the deviation, adjusts if needed and records the result with its measurement uncertainty. Key points:
  • Use references traceable to national standards, ideally through an accredited calibration laboratory.
  • Calibrate in the range where the sensor is actually used, for example at -80 °C for a ULT freezer.
  • Create a stable environment, such as a dry block or an aluminium block inside the equipment.
  • Document which standard was used, the values found and any adjustment. Without written proof, a calibration has no value.

Validation: is the system fit for purpose?

A calibrated sensor says nothing about how a freezer behaves when fully loaded, or whether an alarm reaches the right person at 3 a.m. Validation proves the whole system does what it is intended to do. For monitoring this typically includes:
  • User requirements and a risk assessment.
  • Installation qualification: the right hardware, installed correctly.
  • Operational qualification: alarms, escalation, audit trail and reports work as specified.
  • Performance qualification or mapping where needed.
  • Change control to keep the system in a validated state.

Keeping both current

Calibration intervals, periodic reviews and change control keep the system trustworthy over time. Ignoring calibration recommendations, or using non-accredited providers, can undermine the evidence.

How XiltriX Resilience fits

XiltriX Resilience is an Operational Resilience System built on three layers:
  • Infrastructure: independent sensors and monitoring stations with battery support, resilient connectivity and local data buffering, so a power or network interruption does not create a gap in the record.
  • Intelligence: validated software that turns measurements into alarms, escalation, trends, reports and audit-ready evidence.
  • Care: installation, validation, calibration, preventive maintenance and 24/7 technical support for the monitoring system, delivered by one partner that is ISO 9001 and ISO 27001 certified.

Who does what when an alarm fires

XiltriX Intelligence applies the limits, delays and escalation sequence agreed with the customer, and keeps escalating through the customer's contacts until someone acknowledges. The customer's own team assesses the situation and carries out the physical response.
XiltriX does not respond to the customer's alarms. XiltriX Care provides 24/7 technical support when the monitoring system itself has a problem.

Where to go next

Read data integrity and procurement and URS.