Eigenbrodt ANES 220 Automated Fog Sampler

Overview

The Eigenbrodt ANES 220 Automated Fog Sampler is a precision-engineered environmental monitoring instrument designed for continuous, unattended collection of fog water in meteorological, atmospheric chemistry, and ecological research applications. It operates on the inertial impaction principle—specifically optimized for sub-10 µm liquid aerosol droplets—where ambient air is drawn at a calibrated volumetric flow rate of 125 m³/h through dual inlets mounted on the rear panel. Airflow is guided along a semi-circular deflection surface to suppress turbulence and minimize particle re-entrainment before entering a custom-designed sedimentation chamber. Within this chamber, fog droplets decelerate and coalesce on a capillary-porous compression surface surrounding a central vertical channel. A low-pressure gradient—generated via connection between the central channel and the vacuum pump outlet—ensures laminar flow across the porous surface, enabling efficient droplet retention via combined capillary action and pressure-driven condensate transport toward the central collector. Peripheral raised edges on both sides of the chamber prevent resuspension of deposited liquid under high-velocity airflow conditions. This architecture delivers high collection efficiency (>85% for droplets ≥3 µm), minimal evaporation loss, and negligible backflow contamination—critical for isotopic, ionic, and trace-metal analysis of fog water composition.

Key Features

• Robust all-weather enclosure engineered for year-round operation in alpine, coastal, and remote observatory environments
• Dual-inlet aerodynamic design with turbulence-suppressing semi-circular airflow path and anti-resuspension edge geometry
• Integrated ONED 250 laser visibility sensor for autonomous fog detection and pump activation/deactivation logic
• Programmable visibility threshold triggering (configurable time-integrated hysteresis) to minimize false starts and ensure representative sampling
• Frost-protection protocol: automatic system shutdown when ambient temperature falls below 2 °C, independent of visibility conditions
• Active sample temperature control system with Peltier-based heating/cooling modules maintaining collection bottle temperature within ±1.5 °C of setpoint
• Modular architecture supporting optional base mounting kit and internal data logger (model-specific firmware)
• Compliance-ready design: supports audit-trail-capable logging (when equipped with optional data logger) aligned with GLP documentation requirements

Sample Compatibility & Compliance

The ANES 220 is validated for collection of natural fog condensate across a wide range of liquid water contents (LWC), from light radiation fog (0.01–0.05 g/m³) to dense advection fog (up to 0.5 g/m³). Its inert stainless-steel and fluoropolymer-wetted surfaces minimize analyte adsorption and leaching—ensuring integrity for subsequent ion chromatography (IC), ICP-MS, stable isotope ratio mass spectrometry (IRMS), and organic compound analysis. The system conforms to ISO 9060:2018 (spectral responsivity classification for optical sensors), meets mechanical and electrical safety requirements per IEC 61000-6-2/6-4, and supports operational alignment with WMO Guide to Meteorological Instruments and Methods of Observation (CIMO Guide, Chapter 12). When deployed with the optional data logger, timestamped event logs—including pump start/stop, ambient T/RH, and visibility status—can be exported in CSV format for regulatory reporting under national environmental monitoring frameworks.

Software & Data Management

The ANES 220 operates autonomously without external software; however, its optional integrated data logger (part number ANES-DL-220) records timestamped operational events, ambient temperature (±0.2 °C), relative humidity (±2% RH), and ONED 250 visibility output (in meters) at user-defined intervals (1–60 min). Data are stored on removable microSD card with FAT32 formatting and accessible via standard USB interface. Firmware supports configurable alarm thresholds, data retention cycling, and secure write-lock modes. Exported datasets include ISO 8601-compliant timestamps and are compatible with common environmental data management platforms (e.g., EnviroData, QGIS, MATLAB, Python pandas). No cloud connectivity or proprietary drivers are required—ensuring long-term archival stability and compliance with institutional data sovereignty policies.

Applications

• Long-term fog water chemistry monitoring in mountainous and coastal ecosystems (e.g., cloud forests, fog oases)
• Atmospheric deposition studies of nitrogen, sulfur, heavy metals, and persistent organic pollutants (POPs)
• Stable hydrogen and oxygen isotope (δ²H, δ¹⁸O) characterization of regional moisture sources and transport pathways
• Calibration and validation of satellite-based fog detection algorithms (e.g., MODIS, Sentinel-3 SLSTR)
• Support for WMO Global Atmosphere Watch (GAW) Programme fog observation protocols
• Urban air quality research focusing on ultrafine droplet-mediated pollutant scavenging

FAQ

What is the minimum detectable fog liquid water content (LWC) for reliable sampling?
The ANES 220 achieves consistent collection above ~0.01 g/m³ LWC under typical wind speeds (<5 m/s); performance is validated per DIN EN 12341 ambient aerosol sampling guidelines.
Does the system require routine calibration of the ONED 250 visibility sensor?
Yes—annual field calibration using certified neutral density filters or reference visibility towers is recommended per manufacturer specifications and WMO CIMO guidance.
Can the ANES 220 operate unattended for extended periods (e.g., >3 months)?
Yes, with scheduled maintenance every 6–8 weeks: filter inspection, capillary surface cleaning, and collection bottle replacement; power supply must support continuous 230 VAC or 24 VDC input.
Is the data logger output compliant with FDA 21 CFR Part 11 requirements?
No—the optional logger provides electronic records but lacks electronic signature, audit trail, and role-based access controls required for Part 11; it is intended for environmental research—not regulated pharmaceutical or clinical use.
What materials contact the collected fog water?
All wetted components are electropolished 316L stainless steel, PTFE-coated aluminum, and medical-grade silicone tubing—certified extractables-free per USP Class VI and ISO 10993-5 testing.