Merck Spectroquant® Picco COD/CSB Single-Parameter Photometer
| Brand | Merck |
|---|---|
| Origin | Germany |
| Manufacturer Type | Original Equipment Manufacturer (OEM) |
| Product Origin | Imported |
| Model | Picco COD/CSB |
| Pricing | Available Upon Request |
| Optical System | LED Light Source with Interference Filter at 605 nm |
| Measurement Accuracy | ±3.5% |
| Measurement Time | 3–4 seconds |
| Operating Temperature | 5–40 °C |
| Operating Humidity | 30–90% RH (non-condensing) |
| Power Supply | 9-V Alkaline Battery (≈600 measurements per set) |
| Auto-Off Delay | ~5 minutes after last keypress |
| Safety Certifications | CE compliant per DIN EN 55022, EN 61000-4-2, EN 61000-4-8, EN 50082-2, EN 50081-1, DIN V ENV 50140, EN 50204 |
| Sample Cell Format | 16 mm round glass cuvettes |
| Required Pre-treatment | Digestion using external COD digestion unit (e.g., Merck Spectroquant® Thermoreactor) |
Overview
The Merck Spectroquant® Picco COD/CSB Single-Parameter Photometer is a compact, field-deployable photometric analyzer engineered for rapid, reliable determination of Chemical Oxygen Demand (COD) and Chloride-Stabilized Bromide (CSB) in aqueous environmental samples. Based on the standardized colorimetric method (DIN 38409-H41, ISO 6060, APHA 5220 D), the instrument employs fixed-wavelength photometry at 605 nm—optimized for the chromotropic acid reaction product formed after acidic dichromate digestion. Unlike scanning spectrophotometers, the Picco utilizes a dedicated LED-light source paired with a precision interference filter, ensuring optical stability, minimal drift, and high reproducibility across repeated field measurements. Its design targets laboratories and environmental service providers requiring regulatory-grade COD data without full-spectrum capability or multi-parameter complexity. The system operates exclusively with Merck’s pre-calibrated, factory-validated Spectroquant® COD cell tests—eliminating manual calibration, curve generation, or reagent preparation errors. As a Class I portable device certified to multiple EU EMC and safety directives, it meets essential requirements for routine use under GLP-aligned workflows and supports traceable compliance with national wastewater discharge monitoring programs.
Key Features
- Pre-programmed, factory-stored calibration curves for four COD measurement ranges (10–150 mg/L, 25–1500 mg/L, 300–3500 mg/L, and 500–10,000 mg/L), each validated per ISO 6060 Annex A
- Dedicated 605 nm optical path with temperature-compensated LED and narrow-band interference filter (FWHM ≤ 10 nm) to minimize spectral interference from turbidity or colored matrices
- Integrated 16 mm cuvette adapter with light-tight sealing—designed for consistent pathlength and minimized stray-light error
- Low-power architecture enabling up to 600 measurements on a single 9-V alkaline battery; auto-shutdown after 5 minutes of inactivity conserves energy and extends battery life
- Rugged, IP54-rated housing with shock-absorbing polymer casing and sealed keypad—suitable for transport in mobile labs, wastewater treatment plants, and riverbank sampling stations
- CE-marked per EN 61000-4-2 (ESD immunity), EN 61000-4-8 (power-frequency magnetic field), and EN 55022 (radiated emissions), confirming electromagnetic compatibility in industrial field environments
Sample Compatibility & Compliance
The Picco COD/CSB is compatible with all Merck Spectroquant® COD Cell Tests (Order Nos. 1.14540.0001, 1.14541.0001, 1.14691.0001, 1.14555.0001), which contain pre-dosed potassium dichromate, sulfuric acid, silver sulfate catalyst, and proprietary color-developing reagents in hermetically sealed 16 mm glass cells. Sample digestion must be performed externally using a certified thermoreactor (e.g., Merck Spectroquant® Thermoreactor TR 320 or TR 620) operating at 150 °C for 2 hours—fully compliant with DIN 38409-H41 digestion protocol. The photometer itself does not perform digestion. Post-digestion analysis is limited to clarified, cooled supernatants free of particulate matter >5 µm. The system supports reporting in accordance with ISO/IEC 17025 documentation requirements when used with Merck’s LIMS-integrated test kits and batch-specific certificate of analysis (CoA). It is routinely deployed in municipal WWTPs for effluent compliance monitoring under EU Directive 91/271/EEC and U.S. EPA Method 410.4 equivalents.
Software & Data Management
The Picco COD/CSB operates as a standalone photometer with no embedded software, USB interface, or data logging capability—intentionally designed to reduce validation burden in regulated environments. All measurement results are displayed numerically on a high-contrast LCD screen with automatic unit annotation (mg/L O₂). Users record values manually or transfer them via Merck’s optional Spectroquant® Data Transfer Software (v3.2+) when paired with a PC-connected base station (not included). When integrated into larger QA/QC systems, the instrument supports audit-trail-ready workflows through synchronization with Merck’s LabX Lite platform (requires separate license), enabling electronic signature capture, user access control, and 21 CFR Part 11-compliant data archiving for GLP/GMP audits. Each test kit includes a unique lot-specific calibration certificate referencing NIST-traceable standards.
Applications
- Routine COD screening of influent, effluent, and sludge supernatant in municipal and industrial wastewater treatment facilities
- Field-based compliance verification for discharge permits under local environmental protection agency mandates
- Process control monitoring during biological treatment optimization (e.g., activated sludge SRT adjustments)
- Educational laboratory instruction for standard methods training in environmental chemistry curricula
- Emergency response assessments following industrial spills or sewer overflows where rapid organic load estimation is critical
- Baseline characterization of surface water bodies (rivers, lakes, reservoirs) during seasonal water quality surveys
FAQ
Does the Picco COD/CSB include a digestion unit?
No. Digestion must be performed separately using a certified heating block or thermoreactor meeting DIN 38409-H41 thermal profile specifications.
Can the instrument measure other parameters besides COD?
No. This is a dedicated single-parameter photometer optimized exclusively for COD/CSB at 605 nm. Other Spectroquant® Picco variants exist for Cl₂, O₃, pH, and PO₄³⁻, but they are optically distinct instruments.
What is the minimum detectable COD concentration?
The lowest validated range begins at 10 mg/L (Order No. 1.14540.0001); detection limit is method-dependent and governed by reagent blank variability, not instrument electronics.
Is the 605 nm wavelength adjustable?
No. The optical path is fixed and non-tunable—this ensures metrological consistency and eliminates wavelength selection errors common in multi-band devices.
How often does the instrument require recalibration?
None. Calibration is embedded in each test kit’s pre-loaded curve; no user calibration or zeroing is permitted or required under ISO 6060 or DIN 38409-H41 protocols.
