Ailun AL-4 Pump-Aspiration VOC Gas Detector

Overview

The Ailun AL-4 Pump-Aspiration VOC Gas Detector is a field-deployable, intrinsically safe instrument engineered for quantitative measurement of volatile organic compounds (VOCs) in ambient air using photoionization detection (PID) technology. Based on the principle of ultraviolet (UV) photon-induced ionization—typically at 10.6 eV—the AL-4 selectively ionizes VOC molecules with ionization potentials below this energy threshold, generating a proportional current signal that is linearly converted into concentration units (ppm). Its integrated micro-diaphragm pump enables active sampling at a stable flow rate of 500 mL/min, supporting extended-distance draw (≥10 m via external probe tube), which is critical for confined space entry, pipeline inspection, and hazardous area surveying where operator proximity must be minimized. Designed for continuous operation across extreme environmental conditions—from arctic cold (−40 °C) to industrial heat (+70 °C)—the AL-4 incorporates real-time temperature compensation and a hydrophobic particulate/moisture filter to maintain measurement integrity in high-humidity or dusty environments.

Key Features

• Active pump-aspiration sampling with ≥10-meter reach capability for remote or inaccessible locations
• 2.3-inch high-resolution color LCD with dual-display mode: large-font real-time concentration + dynamic trend curve
• Multi-parameter on-screen display including peak (Max), trough (Min), and rolling average values
• Configurable concentration units (ppm only; no %LEL or mg/m³ conversion per default PID calibration)
• Triple-stage alarm system: 85 dB audible buzzer, bright red LED strobe, and tactile vibration feedback
• Onboard data logging capacity of 100,000 timestamped records with automatic time/date stamping
• Ex ia II CT6 certified intrinsic safety rating for use in Zone 0/1 explosive atmospheres containing hydrocarbons, solvents, and aromatic compounds
• IP65-rated enclosure ensuring protection against dust ingress and water jets during outdoor or industrial deployment
• Rechargeable 4500 mAh Li-polymer battery providing ≥16 hours of continuous operation under typical sampling duty cycles

Sample Compatibility & Compliance

The AL-4 is optimized for detection of common VOCs including benzene, toluene, xylene (BTX), styrene, acetone, isopropanol, ethyl acetate, and chlorinated solvents—provided their ionization potential is ≤10.6 eV. It is not suitable for detecting methane, ethane, formaldehyde, or CO₂. The instrument complies with IEC 60079-0 and IEC 60079-11 for explosion protection, and meets EMC requirements per IEC 61326-1 (industrial environment). While not pre-certified to ISO 16000 series or EPA Method TO-15, its PID response characteristics align with ASTM D5466 (Standard Test Method for Determination of VOCs in Ambient Air by Sorbent Tube/Thermal Desorption/GC–MS) as a screening-level tool. For regulated compliance workflows (e.g., OSHA PEL or EU REACH monitoring), users must perform field calibration using traceable NIST-traceable standard gases prior to each shift.

Software & Data Management

Data retrieval is performed via native USB interface (no proprietary drivers required); recorded files export as CSV-compatible plain-text logs with columns for timestamp (YYYY-MM-DD HH:MM:SS), measured concentration (ppm), battery voltage, and pump status flag. Optional RS232 output supports integration into SCADA or centralized HMI systems for facility-wide gas monitoring networks. Firmware updates are delivered via Ailun’s publicly available Windows-based configuration utility (v2.1+), which also enables adjustable alarm thresholds, sampling interval tuning (1–60 s), and zero/span calibration logging with operator ID tagging—supporting GLP-aligned audit trails. No cloud connectivity or remote telemetry is embedded; all data remains locally resident unless explicitly exported.

Applications

The AL-4 serves as a primary screening instrument across industrial hygiene, environmental compliance, and emergency response domains. Typical use cases include: pre-entry verification of storage tanks, manholes, and silos per OSHA 1910.146; leak detection along refinery flare headers and vapor recovery lines; post-spill assessment of solvent-contaminated soil or groundwater headspace; routine stack or fenceline monitoring in pharmaceutical cleanrooms and semiconductor fabrication facilities; and rapid-response triage during hazmat incidents involving unknown organic vapors. Its lightweight form factor (300 g) and one-handed operability make it suitable for prolonged wear during multi-point surveys conducted by EHS officers, fire department hazardous materials teams, and third-party environmental consultants.

FAQ

Does the AL-4 support calibration with isobutylene or benzene standards?
Yes—calibration gases must match the target analyte’s ionization potential. Isobutylene (IP = 9.3 eV) is the default span gas for broad-spectrum VOC response; benzene (IP = 9.2 eV) may be used for aromatic-specific applications.
Can the instrument operate continuously while charging?
No—USB power input disables internal battery discharge but halts active sampling and data logging during charging.
Is firmware update capability available outside China?
Yes—Ailun provides English-language firmware and configuration software via secure download portal accessible globally upon registration.
What maintenance intervals are recommended for the PID lamp and sensor?
Lamp lifetime is rated at ≥5,000 hours; annual lamp output verification and quarterly zero calibration are advised under daily use.
Does the AL-4 meet FDA 21 CFR Part 11 requirements for electronic records?
No—it lacks electronic signature, audit trail encryption, and role-based access control; it is intended for field screening, not GxP-regulated release testing.