Kalibra² · Gravimetric gas preparation
From weighing to a traceable certificate.
Every batch leaves the balance audit-ready. Kalibra² guides the gravimetric preparation of calibration gas mixtures according to ISO 6142-1 — alongside the analytical balance you already have.
ISO 6142-1
gravimetric preparation, guided step by step
GUMISO/IEC Guide 98-3
compliant uncertainty budget, with covariance
Verified
against an independent analysis (ISO 6143), Eₙ test
ISO 23219
certificate as XML, plus PDF
How it works
Six steps from recipe to certificate.
Fewer errors at the balance
Target pressures and expected readings at every step; weighings that are unstable or go the wrong way are rejected on the spot.
The uncertainty budget, done
Mole fractions, standard uncertainties and covariance according to ISO 6142-1, ISO 14912 and the GUM — calculated, not copied into a spreadsheet.
Verified before it is certified
Every prepared mixture can be checked against an independent analysis — such as a GC analysis calibrated according to ISO 6143 — with the En test.
In detail
Everything a gravimetric lab needs, in one place.
Plan the mixture
- A register of recipes with the target composition; the addition order follows the vapour pressure of the components.
- Components that need a pre-mixture are flagged for dilution.
- Expected uncertainty and ISO 6976 properties estimated before you start, with a warning for condensation risk.
Guided weighing
- Checks on the cylinder retest date, the balance calibration and the shelf life of the base gases.
- Real-gas target pressures and expected balance readings, updated after every step.
- Unstable or wrong-direction weighings rejected; a cooling wait after large pressure steps.
- The air at the balance recorded at every weighing by the Aura; air density and buoyancy effect shown and reported.
Composition and uncertainty
Mole fractions, standard uncertainties and the covariance matrix, following ISO 6142-1, ISO 6976 and ISO 14912, evaluated according to the GUM (k = 2). The budget includes the balance (random and systematic, with correlation), the purity of the base gases, molar masses and dilutions. Calorific value, density, Wobbe index and compressibility follow ISO 6976 with their uncertainty.
Verification
- Each prepared mixture compared with an independent analysis of the same cylinder — for example a GC analysis calibrated according to ISO 6143 in NexChrom.
- Agreement judged with the En test (ISO 13528), taking both uncertainties into account.
- Verifications kept with the preparation, ready for the auditor.
Scope check and certificate
- Results checked against the calibration and measurement capabilities (CMC) of your accreditation scope.
- Certificates as PDF with the content required by ISO 6141, and as ISO 23219 XML.
- An ambient snapshot for every weighing on the record.
Records that hold up in an audit
Cylinders, balances, base gases, customers, recipes, preparations and verifications with an append-only change history. Reminders warn before a cylinder, a balance calibration or a base gas expires.
Standards
Built for reference material producers.
- ISO 17034 — competence of reference material producers
- ISO 6142-1 — gravimetric preparation of calibration gas mixtures
- ISO/IEC Guide 98-3 (GUM) — uncertainty of measurement
- ISO 14912 — conversion of composition data, covariance
- ISO 6976 — calorific value, density and Wobbe index
- ISO 6143 — comparison methods for verification
- ISO 13528 — En test
- ISO 6141 — content of certificates
- ISO 23219 — certificates in XML
- ISO/IEC 17025 — the quality framework
Stand-alone and secure
Kalibra² runs as a local service on Windows or Linux and is used in a web browser — fully offline, without a cloud account or any outside service it depends on. Your preparations and certificates stay in your own lab.
See Kalibra² at work
We gladly walk you through a preparation with Kalibra², from recipe to certificate. Book a demo or ask for a quote.