Megatama Reporting

PT Megatama Inti Akurasi calibrates medical devices for health facilities and kept the work in Excel workbooks. I built the system that replaced them: technicians record measurements against a schema for each device type, and the system computes the results and issues the certificates. It runs as an installable web app that works offline in the field.

• Uncertainty engine. Computes the expanded uncertainty at 95% confidence from tolerances, drift and resolution, following the GUM, and judges each measurement point against its tolerance.
• Schema builder. Admins define the measurement tables, formulas and tolerance rules for 40+ device types, with live checks that block broken formulas.
• Records that stay put. Schemas are versioned and each session keeps the calibrator certificates that were valid on its date, so an issued certificate never changes when a schema or a calibrator does.
• Documents. Certificates, hand-over reports and ASPAK sheets from EJS templates, rendered to PDF by headless Chrome in three tiers: a Cloudflare Worker first, then Browserless.io, then a self-hosted Browserless.
• Electrical safety. IEC 62353 tests whose rows adapt to the device's protection class, cable type and applied part.
• One brand colour. A shared module derives the app's light and dark themes and the certificates' accent from one brand colour, and warns when it fails WCAG contrast.