Lohand LH-COD-K25 Chemical Oxygen Demand Quick Test Kit
| Brand | Lohand |
|---|---|
| Origin | Beijing, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | LH-COD-K25 |
| Pricing | Available Upon Request |
Overview
The Lohand LH-COD-K25 Chemical Oxygen Demand (COD) Quick Test Kit is a field-deployable, colorimetric analytical system engineered for rapid, semi-quantitative determination of COD in aqueous samples. Based on the dichromate oxidation method standardized in ISO 6060 and ASTM D1252 (Method B), the kit utilizes pre-dosed, vacuum-sealed reagent vials containing potassium dichromate, sulfuric acid, and silver sulfate catalyst. Upon sample addition and controlled thermal digestion (typically 150 °C for 2 hours in a portable digester or block heater), organic matter is oxidized, and the resulting color change—proportional to Cr³⁺ formation—is measured visually against a calibrated color scale or quantified using a handheld photometer (e.g., Lohand LH-3BA series). Designed for operational simplicity and minimal infrastructure dependency, the LH-COD-K25 delivers results within 2.5 hours post-sampling, supporting time-critical decision-making in decentralized environmental monitoring workflows.
Key Features
- Pre-calibrated, single-use reagent vials eliminate weighing, dilution, and reagent preparation errors—ensuring inter-operator consistency.
- Integrated digestion vials with integrated reflux condensers reduce risk of sample loss or cross-contamination during heating.
- Color scale card (0–1500 mg/L COD) printed on chemically stable polymer substrate, resistant to humidity and UV degradation during field storage.
- Compatible with Lohand’s certified portable digesters (e.g., LH-10B, 12-volt DC operation) and universal 16-mm digestion blocks meeting ISO 8466-1 dimensional tolerances.
- No requirement for laboratory-grade fume hoods; digestion performed in sealed vials with passive cooling design compliant with IEC 61000-6-3 EMC guidelines for portable instrumentation.
- Reagent shelf life ≥24 months when stored at 4–30 °C in original aluminum-laminated packaging.
Sample Compatibility & Compliance
The LH-COD-K25 is validated for use with raw and treated wastewater, aquaculture effluent, agricultural runoff, hydroponic nutrient solutions, and municipal surface water. It accommodates suspended solids up to 100 mg/L without filtration (per ISO 6060 Annex A guidance). Chloride interference is mitigated up to 2000 mg/L Cl⁻ via mercury-free sulfate masking—aligned with EPA Method 410.4 revision constraints. All reagents comply with GB/T 6682–2008 (Chinese national standard for water used in analytical laboratories) and are manufactured under ISO 9001:2015-certified quality management systems. The test procedure satisfies QA/QC requirements for Level 1 field screening per ISO/IEC 17025:2017 Clause 7.7, including documented analyst training records, batch-specific calibration verification, and control sample analysis.
Software & Data Management
While the LH-COD-K25 operates as a standalone visual or photometric assay, it integrates seamlessly with Lohand’s LH-DataLink mobile application (iOS/Android) for digital result logging, geotagging, and automatic PDF report generation. Data export supports CSV and XML formats compatible with LIMS platforms such as LabWare LIMS and Thermo Fisher SampleManager. Photometric measurements from compatible Lohand photometers include audit-trail metadata (timestamp, operator ID, instrument serial number, ambient temperature) satisfying FDA 21 CFR Part 11 electronic record requirements when deployed with configured user access controls and electronic signatures. Calibration verification data is retained for ≥7 years per GLP archiving protocols.
Applications
- Routine screening of influent and effluent streams at decentralized wastewater treatment units (e.g., rural MBR systems, livestock lagoons).
- Real-time water quality assessment in recirculating aquaculture systems (RAS) to prevent organic loading-induced hypoxia.
- On-farm validation of irrigation source suitability prior to drip or sprinkler deployment.
- Emergency response triage during chemical spill incidents or algal bloom events where lab turnaround exceeds 24 hours.
- Educational use in environmental science curricula for demonstrating redox titration principles and wastewater characterization fundamentals.
FAQ
What is the detection range of the LH-COD-K25 kit?
The visual colorimetric method covers 0–1500 mg/L COD; photometric mode extends lower detection to 5 mg/L with ±5% RSD at 100 mg/L (n=6).
Can the kit be used for seawater or high-salinity samples?
Chloride tolerance is 2000 mg/L; samples exceeding this require dilution or alternative chloride compensation per ISO 6060 Section 8.3.
Is digestion time flexible?
Fixed 120-minute digestion at 150 °C is mandatory to ensure complete oxidation kinetics; shorter durations yield non-representative low bias.
How are results traceable to national standards?
Each production lot undergoes verification against NIST SRM 2633a (COD Standard Solution) and certificate of analysis includes uncertainty budget per GUM (JCGM 100:2008).
Does the kit meet regulatory acceptance for compliance reporting?
It is approved for preliminary screening and internal QA; definitive compliance reporting requires confirmation by accredited laboratory analysis per ISO 6060 or EPA 410.4.
