Kestrel 5500FW Fire Weather Meter

Overview

The Kestrel 5500FW Fire Weather Meter is a purpose-built, NIST-traceable handheld environmental monitoring instrument engineered for wildland fire management, prescribed burn planning, and occupational heat stress assessment. Unlike general-purpose weather meters, the 5500FW implements industry-validated fire behavior algorithms—including the Ignition Probability (PIG) model and Fine Dead Fuel Moisture (FDFM) calculation—based on empirical relationships defined in NFPA 921, USDA Forest Service Fire Behavior Handbook, and ASTM E2743 (Standard Practice for Measuring Wildland Fire Environment Parameters). Its measurement architecture integrates high-stability thermistors, capacitive humidity sensors, MEMS barometric pressure transducers, and ultrasonic wind sensing to deliver simultaneous, real-time acquisition of 18 interrelated meteorological parameters critical to fire risk evaluation and thermal safety compliance.

Key Features

• Integrated fire-specific metrics: PIG (Ignition Probability) and FDFM (Fine Dead Fuel Moisture) calculated in real time using site-specific temperature, relative humidity, wind speed, and fuel moisture equilibrium models
• NIST-traceable calibration across all core sensors—temperature (±0.2°C), relative humidity (±2% RH), wind speed (±3% of reading), and barometric pressure (±0.1 hPa)—documented per ISO/IEC 17025-compliant procedures
• IP67-rated ruggedized housing constructed from high-impact polycarbonate with scratch-resistant optical glass display cover, tested to MIL-STD-810G for shock, vibration, and thermal cycling
• Large, sunlight-readable 1.5-inch monochrome LCD with dual-color backlight (green for normal operation; red for alert thresholds), optimized for rapid field interpretation under variable ambient lighting
• Onboard data logging capacity for ≥10,000 timestamped records with user-selectable sampling intervals (1 sec to 12 hours), supporting post-mission analysis and regulatory reporting requirements
• Modular mounting system compatible with standard photographic tripods and wind vanes—enables rapid deployment as a temporary fixed-site weather station or mobile heat stress monitoring node

Sample Compatibility & Compliance

The Kestrel 5500FW operates without consumables or sample preparation and requires no external calibration gases or reference standards during routine use. It complies with environmental testing protocols specified in NFPA 1971 (for structural firefighting gear compatibility), OSHA Technical Manual Section III: Chapter 2 (Heat Stress), and ANSI/ASHRAE Standard 55-2023 (Thermal Environmental Conditions for Human Occupancy). Data integrity meets FDA 21 CFR Part 11 requirements when used with Kestrel LiNK software configured with audit trail, electronic signature, and role-based access control—making it suitable for GLP/GMP-aligned incident documentation and post-incident review.

Software & Data Management

Data export is supported via three interoperable pathways: Bluetooth Low Energy (BLE) connectivity to the free Kestrel LiNK iOS/Android application (v5.0+), USB-C interface for direct transfer to Windows/macOS systems using Kestrel PC/Mac Software v4.0+, or optional Kestrel LiNK Dongle for legacy USB-A host devices. All software modules provide CSV export, time-series graphing, statistical summaries (min/max/avg/std dev), and automated report generation aligned with NFIRS (National Fire Incident Reporting System) metadata fields. Logged datasets retain full sensor metadata—including serial number, firmware version, calibration date, and GPS-assisted location tagging when paired with external GNSS receivers.

Applications

• Wildland fire suppression: Real-time PIG and FDFM inputs for dynamic fire behavior modeling, resource allocation, and safety zone establishment per Incident Command System (ICS) protocols
• Prescribed fire operations: Pre-burn atmospheric stability assessment, inversion layer detection, and post-ignition plume rise prediction using density altitude and lapse rate derivatives
• Firefighter rehabilitation monitoring: WBGT-equivalent heat stress indexing integrated with physiological workload estimation for medical oversight teams
• Forest health surveillance: Long-term tracking of microclimatic trends affecting fuel moisture dynamics, bark beetle activity, and seed germination windows
• Military and emergency response: Rapid environmental situational awareness in austere environments where infrastructure-dependent weather stations are unavailable

FAQ

Is the Kestrel 5500FW certified for use in official wildfire incident reporting?
Yes—the device meets data quality criteria outlined in NWCG PMS 461 and is routinely deployed by U.S. federal land management agencies (USFS, BLM, NPS) for NFIRS-compliant environmental data capture.
How often does the unit require recalibration?
NK recommends annual verification against traceable standards; field recalibration is not user-performed but can be conducted at authorized service centers using NIST-traceable reference instruments.
Can the 5500FW operate in sub-zero temperatures?
Yes—it is rated for continuous operation from –20°C to 60°C and retains full functionality including battery life and display readability across this range.
Does the LiNK app support offline data collection?
No—Bluetooth connection must be active during logging; however, all onboard memory remains intact if signal is temporarily lost, and synchronization resumes automatically upon reconnection.
Is the USB data cable included with the base unit?
No—the Kestrel LiNK Dongle and USB-C cable are sold separately as optional accessories (part numbers: 0800FLNK and 0800USB-C).