HORIBA OCMA-505 Portable Oil-in-Water Analyzer

Overview

The HORIBA OCMA-505 is a portable, field-deployable oil-in-water analyzer engineered for rapid, on-site quantification of hydrocarbon contaminants in aqueous matrices—including freshwater, seawater, industrial process water, and wastewater effluents. It operates on the principle of non-dispersive infrared (NDIR) spectrophotometry, leveraging the characteristic absorption band of C–H stretching vibrations near 2960 cm⁻¹ (3.39 µm) to selectively detect total petroleum hydrocarbons (TPH) dissolved or emulsified in water. Unlike gravimetric or fluorescence-based methods, NDIR provides chemical specificity for aliphatic and aromatic hydrocarbons while minimizing interferences from humic substances or chlorophyll. The instrument integrates an automated solvent extraction module using HORIBA’s proprietary H-997 extraction solvent—a low-toxicity, high-selectivity chlorinated hydrocarbon blend optimized for recovery efficiency and spectral clarity. Its fully dynamic 0–200 mg/L measurement range eliminates manual range switching, enabling seamless transition from trace-level monitoring (e.g., compliance with EPA Method 1664A limits of 10 mg/L) to high-concentration discharge verification without recalibration or dilution.

Key Features

• True single-range operation: 0–200 mg/L full-scale dynamic quantification with 0.1 mg/L digital resolution and real-time display of measurement uncertainty.
• Integrated micro-extraction system utilizing precision-engineered syringe-driven fluidics to ensure reproducible 10.0 mL sample + 10.0 mL H-997 solvent volumetric delivery—critical for GLP-compliant data integrity.
• Self-diagnostic interface with multilingual (English default) status reporting, including error codes for solvent depletion, optical path contamination, and temperature drift compensation alerts.
• Ruggedized portable chassis rated IP54 for dust and splash resistance, suitable for outdoor deployment in wastewater treatment plants, coastal monitoring stations, and offshore platforms.
• Onboard memory stores up to 1,000 measurement records with timestamp, operator ID, and environmental conditions (ambient temperature, humidity).

Sample Compatibility & Compliance

The OCMA-505 is validated for use with raw surface water, treated municipal effluent, cooling tower blowdown, bilge water, and seawater (salinity up to 35 g/kg). It meets the analytical performance criteria specified in ISO 9377-2:2000 (Water quality — Determination of hydrocarbon oil index — Part 2: Infrared spectrometric method) and aligns with the instrumental requirements of ASTM D7066-04 (Standard Test Method for Determination of Oil and Grease and Selected Petroleum Hydrocarbons in Water by Infrared Spectrophotometry). When operated with documented SOPs and calibrated against NIST-traceable mineral oil standards (e.g., IRM-850), data generated are admissible under regulatory frameworks requiring audit-ready documentation, including US EPA Clean Water Act reporting and EU Water Framework Directive (WFD) monitoring programs.

Software & Data Management

Data export is supported via USB 2.0 interface to PC-based HORIBA OCMA Manager software (Windows 10/11 compatible), which enables batch report generation compliant with 21 CFR Part 11 requirements—including electronic signatures, audit trails for calibration events, and user-access-level controls (administrator/operator modes). All raw absorbance spectra (128-point scans, 4 cm⁻¹ resolution) and extracted peak area integrals are retained with metadata. The software supports trend analysis across sampling locations and time series visualization with configurable upper/lower action limits per site-specific discharge permits.

Applications

• Real-time leak detection at refinery outfalls and petrochemical plant boundaries.
• Compliance verification for NPDES permit holders measuring oil & grease in stormwater runoff.
• Marine environmental surveys assessing hydrocarbon loading in harbor sediments and ballast water.
• Performance validation of oil-water separators and API skimmers in industrial pretreatment systems.
• Field screening during emergency response to pipeline ruptures or tanker spills.

FAQ

What extraction solvent is required for the OCMA-505?

HORIBA H-997 solvent is mandatory—its spectral purity and extraction efficiency are certified for OCMA-series instruments. Substitution with generic CCl₄ or n-hexane invalidates calibration and violates ISO 9377-2 protocol.
Can the OCMA-505 measure diesel, gasoline, or BTEX separately?

No—it reports total extractable petroleum hydrocarbons (EPH) as mg/L mineral oil equivalent. Compound-specific identification requires GC-FID or GC-MS analysis.
Is the SR-305 Solvent Regenerator compatible with all OCMA models?

Yes—the SR-305 is designed exclusively for H-997 regeneration across OCMA-505 and OCMA-550 platforms, extending solvent service life by >80% through dual-stage activated carbon and activated alumina column purification.
Does the instrument require annual factory recalibration?

While not mandatory, HORIBA recommends biannual verification using certified reference materials (CRM) traceable to NIST SRM 2781; full recalibration is advised after 2,000 measurements or exposure to extreme thermal cycling (>30 °C variance).
How is measurement reproducibility verified in routine use?

Built-in dual-standard check function allows daily verification using low- (5 mg/L) and high- (150 mg/L) concentration H-997-spiked water blanks—results automatically logged and flagged if deviation exceeds ±1.5× stated repeatability limits.