CLEAN NIST-Traceable pH Standard Solution CPB401BT

Overview

CLEAN NIST-Traceable pH Standard Solution CPB401BT is a certified reference material engineered for high-accuracy calibration and verification of pH electrodes, meters, and multi-parameter water quality analyzers. As the foundational element in electrochemical measurement traceability chains, its certified pH value of 4.01 ± 0.01 at 25.0°C is directly linked to the National Institute of Standards and Technology (NIST) Standard Reference Materials (SRMs) through documented, unbroken metrological pathways. This ensures compliance with international metrological requirements defined in ISO/IEC 17025, ASTM D1293, and EPA Method 150.1—critical for laboratories operating under GLP, GMP, or ISO 9001 quality management systems. The solution employs a rigorously controlled phosphate buffer formulation, stabilized against microbial growth and CO₂ absorption, and is manufactured under ISO 17034-accredited reference material production conditions. Its red color provides immediate visual identification during routine lab workflows, minimizing operator error during calibration sequences.

Key Features

• NIST-traceable certification with documented uncertainty budget and full metrological chain to SRM 186, SRM 187, and SRM 1967
• Stabilized phosphate buffer system optimized for long-term pH stability and minimal temperature hysteresis
• Batch-specific certificate of analysis (CoA) including measured pH, uncertainty, expiration date, storage conditions, and traceability statement
• Manufactured in an ISO 17034-accredited facility with strict environmental controls (temperature, humidity, particulate filtration)
• Available in two formats: 500 mL amber HDPE bottle (CPB401BT) and 20 L carboy (CPB401C20L), both with tamper-evident seals and lot-numbered labeling
• Compliant with FDA 21 CFR Part 11 requirements when used within validated laboratory information management systems (LIMS)

Sample Compatibility & Compliance

The CPB401BT standard is compatible with all glass-electrode-based pH meters, benchtop analyzers, portable field instruments, and online process sensors used in environmental monitoring, wastewater treatment, drinking water distribution, and pharmaceutical water systems. It meets the acceptance criteria for primary calibration standards outlined in USP , ASTM E70, and ISO 3696 (Grade 2 water purity for preparation). Each batch undergoes independent third-party verification by an ILAC-MRA accredited laboratory. Full compliance documentation—including traceability statements, uncertainty budgets, and CoA archival records—is provided digitally and on paper, supporting audit readiness for regulatory inspections (e.g., EPA, EU Water Framework Directive, MHRA).

Software & Data Management

When integrated into modern calibration management platforms (e.g., MET/TEAM, LabWare LIMS, or Thermo Fisher SampleManager), CPB401BT supports electronic record retention, automated expiry alerts, and audit-trail-enabled calibration event logging. The lot-specific QR code printed on each container links directly to downloadable digital CoAs, raw measurement data, and NIST traceability reports. All documentation conforms to ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available) and supports 21 CFR Part 11 electronic signature validation where required.

Applications

• Primary calibration of pH electrodes prior to environmental water sampling (surface water, groundwater, effluent)
• Verification of instrument performance between calibrations per ISO 17025 clause 7.7.1
• Validation of automated titration systems and continuous pH monitoring loops in municipal water plants
• Reference standard in interlaboratory comparison studies and proficiency testing programs
• Supporting method validation for EPA Methods 150.1, 200.11, and ASTM D5128 in drinking water and wastewater labs
• Calibration anchor point for multi-parameter sondes used in limnological and marine research

FAQ

What does “NIST-traceable” mean for CPB401BT?
It means the certified pH value has been determined using measurement procedures validated against NIST SRMs, with documented uncertainty propagation across the entire calibration hierarchy—from NIST’s primary pH scale to the final product batch.
How should CPB401BT be stored to maintain accuracy?
Store unopened bottles at 15–25°C, protected from direct sunlight. Once opened, use within 6 months if kept tightly sealed and refrigerated at 4–8°C; avoid freezing or repeated temperature cycling.
Is CPB401BT suitable for ISO 17025 accredited laboratories?
Yes—each batch includes a NIST-traceable CoA meeting ISO/IEC 17025:2017 clause 7.7 requirements for reference materials, including uncertainty, stability data, and metrological traceability statements.
Can CPB401BT be used for two-point or three-point pH calibration?
Yes—it is specifically designed as the acidic anchor in standard two-point (pH 4.01 + 7.00) or three-point (pH 4.01 + 7.00 + 10.01) calibration protocols for full-scale electrode characterization.
Does the red dye interfere with pH measurement or instrument optics?
No—the food-grade dye is chemically inert, non-reactive with glass electrodes, and spectrally transparent outside the visible range; it does not affect electrode response time or accuracy.