1. Can the IAQ Monitors be operated indoors, outdoors, or both?
    The indoor air quality (IAQ) monitors are designed for use indoors as the name suggests.  They are usually not for outdoor use since the pollutant (such as CO, NO2, SO2, H2S) levels are typically too low to be properly and accurately measured with the IAQ monitors.


  1. Is it OK that the pump is always running in the IAQ monitor?
    Yes!  Each IAQ monitor has an internal air sampling pump that is on when the unit is operated.  The pump allows for very quick response time for all gas sensors (typically < 1 to 2 minutes) which is much better than simple diffusion used by many of our competitors.


  1. Does the unit need to be plugged in during operations?
    Each IAQ monitor can be operated using either rechargeable battery power or AC power.  With a fully charged battery, each IAQ monitor can run off battery power for at least eight (8) hours.  It is recommended to run off AC power as often as possible.


  1. Why does the CO2 sensor read a negative value when the IAQ monitor is first turned on?
    The IAQ monitor needs to complete a one-minute warm up cycle when first turned on.  During this warm up time, the measurements may not be valid.  After the initial warm up cycle is completed, the IAQ monitor is ready to measure.


  1. Can the gas sensor configuration be customized as requested by the end user?
    Yes, each IAQ monitor can be customized to have the exact gas configuration required (instead of predetermined kits).  Please refer to each product brochure for the gas sensor options and the maximum gas sensors available with each IAQ monitor.


  1. What technologies are used for the IAQ gas measurements?
    There are three types of gas sensors that can be used in the IAQ monitors – electrochemical, NDIR (non-dispersive infrared), & PID (photoionization detection).  The CO2 sensor is an NDIR type of sensor.  The TVOC sensors are PID type sensors.  All of the other gas sensors (such as CO, NO, NO2, SO2, H2S, O2, O3, & CH2O) are electrochemical.  All gas sensors, regardless of technology used, perform their measurements simultaneously.


  1. Can the IAQ monitor be upgraded for additional gas sensors, and can users change sensors from one type to another in the field?
    If a customer wants to upgrade the IAQ monitor to add a gas sensor that was not previous included, this is considered an upgrade and the product must be returned to the Langhorne, USA factory for upgrades.  Gas sensors cannot be changed from one type to another (such as replacing CO sensor with SO2 sensor) in the field.  When a sensor dies and needs replacement in kind, this can be done locally.


  1. Which gases are measured with the TVOC sensor, and what are the TVOC measuring ranges available?
    The TVOC (Total Volatile Organic Compounds) sensor can measure VOCs with an ionization potential of 12.6 eV or lower.  A chart showing the ionization potentials for several hundred of the more common VOCS is included with each Si-AQ VOC & Si-AQ Expert monitor.  There are two TVOC sensors available – the low range is 0 to 20,000 ppb (20 ppm) and the high range is 0 to 200 ppm.  When measuring VOCs, you must choose a low or high range TVOC sensor (not both).


  1. Since Formaldehyde is a VOC, why would need I need a separate sensor for this gas?
    Yes, this is because formaldehyde (CH2O) has an ionization potential above 12.6 eV and will not be detected by the TVOC sensor.


  1. How can data be saved with the IAQ monitor, and how much data can be stored?
    Data can be saved to the internal memory of the IAQ monitor either manually or automatically through the keypad.  Automatic data saving and logging can be done by selecting how frequently the data is saved.  You can also save data using the real-time PC software that is included with each product.  The internal memory can hold up to 2000 tests while you have virtually unlimited memory if data is saved directly to a PC or tablet using the software.  Each “test” is one date/time stamped snapshot in time that includes all parameters that the IAQ monitor is capable of measuring and calculating.


  1. Is there software available for the IAQ Monitor?
    Yes, each IAQ monitor includes real-time software that communicates via wireless Bluetooth® and USB cable at no extra cost.  The Si-AQ PCSoft software allows the operator to view, save, and graph data in real-time on a Windows computer or tablet.


  1. How often should each IAQ Monitor be calibrated?
    The factory recommendation is to recalibrate each IAQ monitor at least once each year.  Depending on the application, and especially if the TVOC is included, more frequent calibrations may be needed.


  1. What is the expected life of each gas sensor?
    The typical life of each gas sensor is 2 to 5 years.  This sensor life is partially dependent on the particular application where the product is operated and the total hours of operations.


  1. What is the standard warranty period for each IAQ Monitor?
    Each of the IAQ monitors, including all gas sensors, have a standard one-year warranty period.