Archive Management System for Online Oil-in-Water Analyzers

Continuous fluorescence-based oil-in-water analyzers generate large volumes of digital records (calibration logs, alarm events, maintenance tickets, raw spectra, and validated concentration data). A concise yet compliant archive policy should therefore cover four layers:

Acquisition Layer

Auto-save every measurement together with time-stamp, GPS tag, operator ID, and QC flag.

Use 21 CFR Part 11-compliant firmware that appends an SHA-256 checksum to each record to guarantee integrity.

Transfer & Storage Layer

Push encrypted files (AES-256) to a central PostgreSQL server every hour via HTTPS; keep a local redundant copy on the analyzer’s 32 GB industrial SD card for 30 days in case of network failure.

Employ a two-bucket rule: “hot” data younger than 90 days stay on fast SSD for instant trending; “cold” data migrate to RAID-6 HDD with WORM (write-once-read-many) setting to prevent deletion.

Retention & Retrieval Layer

Environmental regulators normally ask for five years of hydrocarbon discharge evidence; set automatic retention to 5 years + 1 day, then move files to off-line LTO tape stored in a fire-proof cabinet.

Maintain an elastic-search index so any historical record can be located within 3 seconds by serial number, date range, or alarm type.

Security & Audit Layer

Role-based access: only Level-3 supervisors can delete, and even that action is logged in an immutable audit table.

Once per quarter the QA manager runs a verification script that compares a random 1 % sample of archived data with the original printout; discrepancies trigger a CAPA (Corrective & Preventive Action) report.

By integrating these four layers, the plant satisfies ISO 14001, EPA 40 CFR 435, and internal ISO/IEC 27001 controls—while still keeping the archive lean, searchable, and court-admissible.