YSI 5000 Series Laboratory BOD Analyzer

Overview

The YSI 5000 Series Laboratory BOD Analyzer is a precision-engineered electrochemical system designed for standardized biochemical oxygen demand (BOD) measurement in environmental and wastewater laboratories. It operates on the polarographic (Clark-type) dissolved oxygen (DO) sensing principle, utilizing temperature-compensated amperometric detection with a pre-tensioned 5906 membrane electrode. The instrument complies with key regulatory methodologies including ASTM D5210–22 (Standard Test Method for Determining Biochemical Oxygen Demand of Diluted Wastewater), ISO 5815-1:2016 (Water quality — Determination of biochemical oxygen demand after n days — Part 1: Dilution and seeding method), and U.S. EPA Method 405.1 (Dissolved Oxygen – Electrochemical Probe Method). When paired with the YSI 5010 self-stirring BOD probe and YSI 5120 BOD Analysis Software, the system fully automates the 5-day BOD₅ test per ISO 5815-1 and GB 7488–1987, eliminating manual data transcription, reducing operator-induced variability, and ensuring traceable, audit-ready results.

Key Features

• Integrated real-time clock with date/time stamping for all stored measurements — essential for GLP-compliant recordkeeping
• Backlit LCD display with intuitive menu navigation — optimized for glove-compatible operation in regulated lab environments
• Onboard data storage for up to 100 measurement sets, including DO (mg/L and % air saturation), temperature, and stability flags
• RS-232 serial interface compliant with LIS/HIS integration protocols — supports bidirectional communication with LIMS and laboratory informatics platforms
• Probe-powered architecture — eliminates external power supplies and reduces cable clutter on benchtops
• Tactile and audible keypad feedback — minimizes input errors during multi-step BOD protocol execution
• Auto-stabilization algorithm — detects DO equilibrium per ASTM D888 criteria before triggering endpoint capture
• User-upgradable firmware — ensures long-term compatibility with evolving regulatory software requirements without hardware replacement

Sample Compatibility & Compliance

The YSI 5000 is validated for use with domestic and industrial wastewater, surface water, groundwater, and treated effluent samples across the full operational range of −5 °C to +50 °C. Its 5010 self-stirring probe maintains consistent 200 rpm agitation — meeting ISO 5815-1’s requirement for uniform mass transfer at the electrode surface. Membrane integrity monitoring continuously verifies 5906 cap integrity; automatic alerting prevents erroneous readings from compromised sensors. The system meets electrical safety standards IEC 61010-1 and EMC directive 2014/30/EU. For regulated environments, the YSI 5120 software provides full 21 CFR Part 11 compliance via electronic signatures, audit trails, and role-based access control.

Software & Data Management

YSI 5120 BOD Analysis Software runs on Windows-based laboratory PCs and interfaces directly with the 5000/5100 analyzer via RS-232. It automates complete BOD₅ workflows: auto-capturing initial and final DO values, applying dilution factor correction, computing BOD concentration using the standard formula, and generating printable reports with embedded metadata (sample ID, analyst, incubation dates, temperature logs). Advanced functions include automatic blank compensation, seed correction per Standard Methods 5210B, extrapolation of non-5-day BOD values (e.g., BOD₃, BOD₇), and derivation of first-day DO values for alternate dilutions. All data files are saved in CSV and XML formats for third-party statistical analysis or regulatory submission.

Applications

• Regulatory wastewater discharge monitoring under NPDES permits
• Wastewater treatment plant process control and efficiency evaluation
• Environmental impact assessment (EIA) studies requiring BOD₅ quantification
• Academic and research laboratories conducting aerobic biodegradability testing
• Drinking water source protection programs assessing organic loading in reservoirs and rivers
• Validation of alternative BOD methods against reference standard procedures

FAQ

Does the YSI 5000 comply with U.S. EPA Method 405.1 for dissolved oxygen measurement?
Yes — its polarographic sensor, temperature compensation algorithm, and calibration verification procedures align with EPA 405.1 requirements.
Can the YSI 5000 perform respirometry tests such as OUR and SOUR?
Only the YSI 5100 variant includes built-in oxygen uptake rate (OUR) and specific oxygen uptake rate (SOUR) calculation modules per USEPA Method 503.
Is the 5906 membrane electrode certified for GLP/GMP environments?
The pre-tensioned 5906 cap is supplied with lot-specific QC documentation and is compatible with IQ/OQ/PQ validation protocols.
How does the system handle over-saturated or temperature-out-of-range samples?
It triggers visual and audible alerts and flags affected datasets in memory — preventing inclusion in final BOD calculations.
What barcode standards does the optional YSI 5015 reader support?
The scanner reads Code 39, Code 128, and Interleaved 2 of 5 barcodes — enabling seamless sample ID ingestion into 5120 software.