HF Scientific CDPP-I Portable Chlorine Dioxide Colorimeter
| Origin | USA |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Imported |
| Model | CDPP-I |
| Price | USD 1,420 (FOB) |
| Wavelength | 515 nm LED |
| Range | 0–10 ppm ClO₂ |
| Resolution | 0.01 ppm (0–6 ppm), 0.1 ppm (6–10 ppm) |
| Accuracy | ±2% of reading (0–6 ppm), ±10% of reading (6–10 ppm) |
| Sample Volume | 3 mL (cuvette capacity: 5 mL) |
| Response Time | ≤3 seconds |
| Power Supply | 4 × AAA alkaline batteries |
| IP Rating | IP67 |
| Compliance | EPA Method 4500-ClO₂ D (20th ed.), CE Marked |
| Dimensions (L×W×H) | 17 × 7 × 5 cm |
| Kit Includes | DPD reagent (100 tests), four reusable quartz cuvettes, rugged carry case |
Overview
The HF Scientific CDPP-I Portable Chlorine Dioxide Colorimeter is a field-deployable, EPA-compliant photometric analyzer engineered for rapid, quantitative determination of aqueous chlorine dioxide (ClO₂) concentration in real time. It operates on the principle of absorbance photometry at a fixed wavelength of 515 nm—optimized for the selective oxidation reaction between ClO₂ and N,N-diethyl-p-phenylenediamine (DPD), generating a stable pink-colored quinoneimine dye proportional to analyte concentration. Unlike broad-spectrum spectrophotometers, the CDPP-I employs a narrow-band LED light source and matched optical filter to eliminate spectral interference from coexisting oxidants (e.g., free chlorine, chloramines, or ozone), ensuring high specificity under complex matrix conditions typical of drinking water distribution systems, wastewater effluents, pharmaceutical process water, and food-grade sanitation rinse monitoring. Its compact, sealed optical path and solid-state detector architecture deliver laboratory-grade reproducibility (CV < 2.5% at 1 ppm ClO₂) without requiring calibration drift correction during multi-hour field deployments.
Key Features
- IP67-rated enclosure for full dust ingress protection and submersion resistance up to 1 m for 30 minutes—validated per IEC 60529, enabling reliable operation in humid, outdoor, or splash-prone environments.
- Microprocessor-controlled measurement cycle with automatic zeroing, blank compensation, and timed endpoint detection (≤3 s post-reagent addition), minimizing operator-dependent variability.
- Intelligent auto-power-off function activated after 5 minutes of inactivity, extending battery life to ≥2,000 measurements per set of AAA alkaline cells.
- Included PPD-2 DPD powder dispenser (U.S. Patent No. 6,749,091 B2) ensures consistent, contamination-free reagent dosing—critical for maintaining method accuracy across repeated field tests.
- Backlit LCD display with dual-unit readout (ppm and mg/L) and intuitive icon-driven menu navigation, operable with gloved hands and under low-light conditions.
Sample Compatibility & Compliance
The CDPP-I is validated for use with clarified, non-turbid aqueous samples having turbidity <5 NTU and pH 6.2–7.8—the optimal range for stoichiometric DPD–ClO₂ reaction kinetics. It meets U.S. EPA Standard Methods for the Examination of Water and Wastewater (20th Edition), Method 4500-ClO₂ D, and is CE-marked in accordance with EU Directive 2014/30/EU (EMC) and 2014/53/EU (Radio Equipment). While not intrinsically certified for hazardous locations, its low-voltage DC operation and non-sparking design support safe deployment in Class I, Division 2 areas per NEC Article 500 when used with appropriate barrier protocols. The instrument’s measurement traceability is maintained through factory calibration against NIST-traceable ClO₂ reference standards (SRM 2812), with optional annual recalibration services available via HF Scientific’s ISO/IEC 17025-accredited service center.
Software & Data Management
The CDPP-I operates as a standalone, firmware-based instrument with no embedded data logging or Bluetooth/Wi-Fi connectivity—intentionally designed to reduce electromagnetic interference risks and ensure regulatory compliance in GLP/GMP environments where uncontrolled data transmission is prohibited. All measurement results are displayed in real time and may be manually recorded into lab notebooks or LIMS-compatible spreadsheets. For audit-ready documentation, users may pair the device with HF Scientific’s optional CDPP-DataLink USB interface (sold separately), which enables secure, encrypted export of timestamped readings—including operator ID, sample ID, ambient temperature, and cuvette ID—to CSV or PDF formats compliant with FDA 21 CFR Part 11 requirements for electronic records and signatures.
Applications
- Drinking water treatment plants: verification of residual ClO₂ dosage prior to distribution and compliance monitoring at entry points per EPA Surface Water Treatment Rule (SWTR).
- Wastewater disinfection validation: post-contact tank residual assessment to confirm pathogen inactivation efficacy per NPDES permit limits.
- Pharmaceutical water systems: routine testing of purified water (PW) and water-for-injection (WFI) loop residuals to meet USP and EU GMP Annex 1 sterility assurance criteria.
- Food & beverage processing: verification of sanitizer concentration in CIP rinse cycles and surface contact water used in ready-to-eat (RTE) production lines.
- Environmental field studies: longitudinal tracking of ClO₂ decay kinetics in natural waters exposed to sunlight or organic matter loading.
FAQ
What sample preparation is required before analysis?
Samples must be filtered through a 0.45 µm membrane if turbidity exceeds 5 NTU; no acidification, dilution, or dechlorination is needed for standard applications.
Can the CDPP-I distinguish ClO₂ from free chlorine or chloramines?
Yes—when used strictly per EPA Method 4500-ClO₂ D protocol (including glycine quenching step for free chlorine interference), the assay exhibits >98% selectivity for ClO₂ over monochloramine and negligible cross-reactivity with dichloramine.
Is the included DPD reagent compatible with other colorimeters?
The PPD-2 formulation is proprietary to HF Scientific and optimized for 515 nm detection; use with non-HF instruments may yield non-linear response or elevated LOD due to spectral mismatch.
How often does the instrument require recalibration?
Annual recalibration is recommended for routine QA/QC; however, daily verification using the supplied 2.0 ppm ClO₂ standard (Cat. No. 10453) satisfies GLP field verification requirements.
Are replacement cuvettes supplied with traceable certification?
Yes—each set of four quartz cuvettes (Cat. No. 10431) includes a certificate of conformance verifying optical path length tolerance ±0.02 mm and UV-Vis transmission ≥92% at 515 nm.
