Founded in 1980, Unisearch became a pioneer and, consequently, a world leader in the use of systems based on Tunable Diode Laser Absorption Spectroscopy (TDLAS) and (TDL) for trace gas measurements – a position it still enjoys today.

Unisearch is a team of people committed to mutual respect, professional conduct and a passion for excellence. Our worldwide network of technical sales representatives is complemented by a full staff of installation and service experts to ensure that your equipment and monitoring systems to ensure these processes operated at peak efficiency. Applications include ammonia, carbon monoxide, oxygen, nitric oxide and hydrogen chloride analyzers for the power industry, hydrogen fluoride monitors for the aluminum industry, methane, carbon dioxide, carbon monoxide and hydrogen sulfide systems for ambient air, fire detection and combustion applications for the steel and nickel industries. Our top of the line systems, such as those based on Tunable Diode Laser Absorption Spectroscopy (TDLAS), will ensure efficient gas monitoring of a wide variety of gasses.

In the early years Unisearch was primarily an R&D organization building mid-infrared laser based air quality measurement systems for governments and research institutions. In 1984 Unisearch manufactured its first commercial instrument. The patented high sensitivity (sub-ppbv) LUMINOx NO2 monitor was developed and several hundred units sold prior to divestiture of the technology in 2005 as a consequence of changing focus to optical products and their applications.

In 1993 the company developed a Differential Optical Absorption Spectrometer (DOAS) system for ambient air monitoring. After temporarily licensing the technology to Thermo Environment Instruments from 1995 through 2005, Unisearch reacquired it and currently manufactures in-situ and extractive versions of the DOAS analyzer.

In 1995 Unisearch acquired advanced Fourier Transform Infrared (FTIR) technology from Radian Corporation and opened its Austin, Texas, plant to manufacture FTIR instruments. The company developed and installed a number of FTIR systems, for fence line monitoring and in-situ stack and extractive systems for continuous emissions monitoring (CEMS) and process control. Unisearch divested its interest in the US operation in the early 2000’s and the technology was acquired by IMACC Inc. based in Austin, Texas. Nonetheless, the knowledge is retained within the company and several systems are available for field testing and in-house R&D.

In 1994 the company introduced the LasIR line of instruments which extended our early mid-infrared TDL technology to the Near Infrared by employing Tunable Diode Laser Absorption Spectroscopy (TDLAS) lasers developed for the telecommunications industry. The LasIR quickly became the core product for Unisearch. Applications for the LasIR instruments include air quality measurements, fence-line monitoring, fire detection, CEMS and process control. Instruments have been sold to various industries with over 800 installation sites and thousands of monitoring points worldwide. Our network of service representatives ensures proper maintenance and rapid response for any issues.

In 2013 Unisearch demonstrated the use of mid-IR quantum cascade lasers for in-situ high sensitivity measurement of industrial gases. A commercial version of the analyzer is scheduled for release by the end of 2014.

Unisearch has acquired patents on instruments and applications of its technology. The continued focus on, and level of R&D at Unisearch ensures that our products will always represent the best available technology in the years to come.

Instruments - LasIR

LasIR gas measurement instruments are based on the absorption of light in the infrared region of the spectrum. Their unique light source is a tunable diode laser – a tiny solid state device, the laser emission wavelength of which depends on the composition of the lasing chip, the temperature and the current passing through the chip. The standard LasIR employs lasers in the red to Near Infrared region (700 – 2700 nm) which are similar to those found in consumer products such as CD players, but the laser wavelength can be tuned to the gas absorption feature of choice. The light emitted from these lasers can be fiber-coupled, allowing the analyzer electronics to be located hundreds of meters from the actual measurement point. This is an important feature for measurement locations that are not easy to access or are in hazardous locations. It is also possible to multiplex the laser to multiple locations (up to 16 as standard), allowing measurement of the gas at multiple locations with a single analyzer. This makes the system very cost effective. The same system can be used for in-situ and/or extractive gas measurements in any combinations.

Recently, Unisearch developed its LasIR-QC system employing Quantum Cascade (QC) lasers which emit in the mid-infrared wavelength region (3.5 – 10 microns). Very high sensitivities (parts per billion level) can be achieved with such laser devices. At present fiber-coupled QC lasers are not commercially available. This limits the gas measurement to a single location. LasIR and LasIR-QC analyzers are factory calibrated and do not require field calibration. The analyzers can be audited for stability and linearity. Permanently-sealed inline as well as built-in flow-through gas cells are available for this purpose.

Gas Monitoring Equipment: an analyzer/controller that takes readings at specified intervals in a smoke stack. It enables the manufacturer to keep the waste gas emissions of the manufacturing process within the government-mandated regulation limits and sound alarms when nearing maximum limits. Instruments included: LasIR RM410 units and LasIR RB110 units.

Portable Gas Monitoring equipment: LasIR RP130 units – point monitor analyzers that can be hand carried to make measurements of the target gas in the area.

Environmental Process Monitoring: The analyzer is used in a manufacturing facility. It aids the manufacturing process by maximizing efficiency, especially when the gas being analyzed is recaptured for sale as a byproduct. All types of Unisearch analyzers are capable of this process.

Fence-Line Monitoring for Perimeter Monitoring: Used to estimate fugitive emissions from landfills, petro-chemical plants and any industries that may be emitting regulated gases.

Ambient Air Quality Monitoring: can be used by government agencies to determine ambient gas conditions.

Gas Applications: HCl (Hydrogen Chloride gas) Monitoring, NH3 (Ammonia gas) monitoring, HF (Hydrogen Fluoride gas) monitoring, O2 (Oxygen gas) monitoring, H2O (Moisture) monitoring, CH4 (Methane gas) monitoring, CO (Carbon Monoxide gas) monitoring, CO2 (Carbon Dioxide) monitoring, NO (Nitric Oxide gas) monitoring, H2S (Hydrogen Sulfide gas) monitoring, HCN (Hydrogen Cyanide gas) monitoring, HDO/D2O (deuterated water) monitoring and various Hydrocarbon and Fluorocarbon gas monitoring.

Services - R&D

Since its formation in 1980, Unisearch Associates has been providing Research and Development and measurement services to a wide range of clients including Government (Ontario Ministry of the Environment, AES Canada, California ARB, US EPA, NASA), Universities (York University Toronto, the University of Toronto, MacMaster University, the University of East Anglia, the University of Duisburg at ESSEN), Research institutes (the Electric Power Research Institute, the Coordinating Research Council, Argonne National Laboratories, Lawrence Berkeley Laboratories), and industry (Aluminium Association of Canada, ALCOA, RIO TINTO-ALCAN, Philip Morris International, Metro Wastewater Reclamation District—Denver, Air Liquide, BAE Systems) to mention just a few.

Unisearch has a strong research team of physicists, chemists and engineers who support both the external R&D and Services and also internal R&D which develops new and improved products.  Unisearch maintains over 5,000 sq. ft. of Production, Service and R&D space including fully equipped test facilities and diagnostics to keep our continuous emissions monitoring equipment and other products at the leading edge of the industry.

Current contract R&D includes:

• QC Laser Monitor: Development of Quantum Cascade laser based systems to extend our measurement capabilities to the mid Infra-red region.
• Near IR LasIR:  Extension of our Near Infra-red laser product line to longer and shorter wavelengths opening up more species to our standard LasIR product line. 
• NH₃ Slip Monitoring:  combustion efficiencies
• CO and CO₂ Monitoring: Measurements at Coal Fired Power plants to help improve NOx reduction strategies.
• HCl Monitoring: Support EPRI and EPA in measurements of HCl at Coal Fired Power plants with the objective of providing a protocol for CEMS monitoring of this species with high accuracy and response time coupled with minimizing maintenance intervals.
• Fire Detection: Using tunable diode laser technology.
• Measurement of SO₂ (0-100% with no dilution requirement): For metal smelters
• High sensitivity measurement of SO₂ (0-100 ppbv): For low sulfur diesel vehicle exhaust