AQS 1 Introduction

The Dust Sentry and AQS 1 (referred to herein as a ‘monitor’) are flexible air quality monitoring systems that can be configured to target specific applications of interest in industrial, urban environment and regulatory applications.

The monitor incorporates key technology features that allow it to deliver data with very strong correlation to EPA-approved monitors – ‘Near Reference’­ – over extended periods of time, several years with appropriate maintenance.

Housed in a rugged, lockable weatherproof (IP 65) enclosure. The monitor includes an embedded PC, modem and full software system for remote technical support, data management and analytics.

The instrument is designed to connect to Aeroqual’s Cloud software suite (purchased separately) which enables remote access to the monitor, a project management toolset, and online technical support. This can be accessed through a web browser, such as Microsoft Edge, Firefox, Chrome, or Safari. Alternatively, users have the option to connect directly to the embedded PC, which runs a proprietary monitor operating system called Aeroqual Connect.

The PCX module is a light scattering based, optical particle counter like the Profiler module, with several important advantages. The PCX module has the capability to report 5 particle mass channels (PM₁, PM_2.5, PM₄, PM₁₀, and TSP) in addition to 6 particle count channels (optional) and includes several ‘smart’ features that improve the performance while reducing operator burden.

·         Integrated Flow Management: Active flow control maintains the flow rate at a steady 1 L/min, ensuring all particles are sized and counted correctly, and minimizing setup and maintenance time by reducing the need for flow checks.

·         Dynamic Heater Control: The PCX module has an integrated inlet heater that can be controlled dynamically if the PCX module is equipped with a temperature and humidity sensor measuring the ambient conditions. This allows for automatic control to the minimum required temperature (and subsequently power consumption) to reduce humidity interference, resulting in increased power savings.

·         Advanced Failure Warning: The PCX module can automatically notify you in the event maintenance may be required. By monitoring and recording the amount of particulate through the module, the instrument can notify you when a filter may require replacement. The system will also monitor pump speed relative to module flow rate and can raise a warning in the event a pump may soon need replacing.

The sensor combines a laser nephelometer with a high-precision sharp cut cyclone to give accurate real-time measurement of ambient particulate matter. By changing the sharp cut cyclone, the particle sensor can be used to measure PM_2.5, PM₁ or TSP. For simultaneous measurement, see the PCX Module.

A nephelometer is an optical sensor that uses light scattering from particulate matter to provide a continuous real-time measurement of airborne particle mass. The light source is a visible laser diode and scattered light is measured in the near forward angle using focusing optics and a photo diode. The nephelometer has an on-board temperature sensor that corrects for thermal drift, sheath air filter to keep the optics clean, automatic baseline drift correction, and a fibre optic span system to provide a check of the optical components.

The sharp cut cyclone is a precision-engineered component fitted to the AQS 1 inlet that physically selects particles of a target size e.g. PM₁₀ targets particles <10 microns. This ensures precise measurement of only the size fraction of interest. The inlet is fitted with a heater that is used to remove moisture from the incoming sample. Moisture can reduce the accuracy of optical measurement, so for best results the inlet heater is activated in the event of high humidity.

Aeroqual's gas modules are a reliable and accurate solution for monitoring gaseous pollutants. The gas modules come pre-calibrated from the factory and are traceable to NIST Standard Reference Materials. They can also be calibrated in the field against US EPA protocol gas standards, if necessary.

In addition to particulate matter monitors can be configured to monitor up to 3 of the following gases:

·         O₃

·         NO₂

·         CO

·         VOC

·         H₂S

·         SO₂

·         CH₄

Note: Gas module are only available in an Aeroqual AQS, however Dust Sentry and Dust Sentry Pro can be upgraded to work with gas modules.

The monitors can integrate several external sensors such as weather sensors, solar radiation and noise sensors. These sensors are mounted outside the monitor enclosure. The external sensors below are available factory tested and ready to connect to the monitors.

Cirrus MK427 noise meter	Vaisala WXT536 weather station	Gill Instruments Windsonic	Li-Cor LI-200 Pyranometer	Airmar 200WX

These dimensions are for a visual representation only,.

DS or AQS1 with PCX Module

DS or AQS1 with Nephelometer

DS Pro or AQS1 with Profiler

Dimensions are in millimetres and (Inches).