History
ESC Spectrum has a long history of helping companies meet air emissions compliance. Before officially becoming ESC Spectrum in 2020, Environmental Systems Corporation and Spectrum Systems spent decades innovating software and hardware solutions and providing professional CEMS and DAS services. No other company offers the combined knowledge, expertise and care that ESC Spectrum provides to its customers in a variety of different industries. In December of 2021, ESC Spectrum acquired Monitoring Solutions and on February 2, 2022, acquired Control Analytics.
ESC Spectrum History: A Timeline of Innovation
A small group of investors, researchers from Oak Ridge National Labs, and faculty members from the University of Tennessee founded Environmental Systems Corporation (ESC) to investigate the effects of thermal discharge from fossil-fired power plants into native waterways. It was headquartered in an airplane hangar at the Knoxville, TN airport. Employees used a small plane to take Infrared photographs of the river, and their phone calls were often interrupted by the sound of the engine noise.
The enactment of the Clean Air Act of 1970 resulted in a major shift in the federal government's role in air pollution control. This legislation authorized the development of comprehensive federal and state regulations to limit emissions from both stationary (industrial) sources and mobile sources.
ESC developed its first Data Acquisition and Reporting System for a project to continuously monitor the performance of a series of demonstration solar homes built by the Tennessee Valley Authority (TVA) around the Tennessee Valley region. ESC also created their first data loggers - the SDL-80 (Solar Data Logger) and CDL-80 (Cassette Data Logger).
H. Gordon Jones founded Spectrum Systems, Inc. after leaving his job as a field technician.
ESC sold its first commercial Data Acquisition Reporting Systems to state and local government agencies to monitor ambient air quality. The systems were based on the AQM-8000 series data loggers (Air Quality Monitoring) and utilized the then powerful Digital Equipment Corporation (DEC) mini-computers and long-distance dial-up telephone modems. Customers included the State of Kentucky, Pennsylvania Electric Company (PENNELEC), and the Santa Barbara (CA) Air Quality Monitoring District.
At this time, ESC offered both DOS-based and UNIX-based data acquisition systems and introduced the next-generation 8800 Data Logger. Over 38 of the 50 U.S. states used ESC systems for ambient air quality monitoring. Continuous Emission Monitoring systems (CEMS) started to employ ESC's Data Acquisition Systems for stack emissions monitoring in electric power plants.
Spectrum Systems appeared in Fortune Magazine's list of Fortune 500 companies.
Spectrum Systems moved into its current home on 9 Mile Road. The building and grounds once housed a visitor's center and was located at the first highway exit in Florida.
The 1990 amendment of the EPA's Clean Air Act introduced a nationwide approach to reducing acid pollution. It was designed to reduce acid rain and improve public health by dramatically reducing emissions of sulfur dioxide (SO2) and oxides of nitrogen (NOx).
Spectrum Systems built the first CEMS shelter for Georgia Power, and debuted the Spectrum System Model 20/20 "for perfect hindsight".
After the passage of the Clean Air Act Amendments of 1990, ESC was well-positioned to serve the monitoring requirements of the subsequent Acid Rain Program (as codified in 40 CFR 75). ESC released the 8816 Data Controller and the UNIX-based E-DAS Expert for UNIX. Power plant stacks used ESC data controllers and Data Acquisition System software more than any other vendor.
Spectrum Systems released the SpectraView Data Acquisition System for UNIX.
The first ESC Continuous Emissions Monitoring System (CEMS) and Data Acquisition System (DAS) User Group Meeting was held in Knoxville, TN.
ESC introduced E-DAS Ambient and E-DAS EMR for Windows.
ESC debuted the 8832 Data Controller, and Spectrum Systems introduced the Spectra-Pak E Data Logger.
ESC formed another company, Agilaire, to support the ambient air quality monitoring market. This allowed ESC to focus on CEMS.
Yeehaw! ESC moved its corporate office to Austin, TX.
ESC acquired Spectrum Systems. The two companies joining increase the number of employees to over 100.
ESC Spectrum introduced QAInsight to help facilities solve the challenges of scheduling, planning, and tracking activities related to performing Quality Assurance (QA) tests required by state and federal agencies.
ESC Spectrum introduced FleXReports to securely export data from StackVision™ into Microsoft® Excel for maximum flexibility. Partner with expert teams of Reporting, Engineering, and IT experts for help with CEM challenges.
On January 1, 2023, Monitoring Solutions and Control Analytics legally changed their names to ESC Spectrum.
In May 2023, ESC Spectrum introduced the 8864 Data Controller Generation 2, offering faster communication and an updated interface with customizable dashboards.
In November 2023, ESC Spectrum hits a milestone of 200 employees across the U.S.
On April 4, 2025, ESC Spectrum announced its successful demonstration of Integrated Path CEMS Technology for Part 75 compliance, which provides a cost-effective solution for the electric power industry.
From The Source Blog
Air Emissions Calibration Testing: Staying Compliant With Daily and Quarterly Requirements
Accurate air emissions calibration testing is essential for maintaining compliance and ensuring reliable CEMS performance. This blog breaks down daily and quarterly calibration test requirements, explains how offline calibrations are used, and clarifies what causes out-of-control data.
Alliance Technical Group Acquires ESC Spectrum, Cementing Global Leadership in Continuous Emissions Monitoring (CEMS) and Data Acquisition Systems (DAS)
ESC Spectrum is now part of Alliance Technical Group, combining forces to deliver the most comprehensive CEMS and DAS compliance platform in the industry. This strategic acquisition strengthens our ability to serve customers with expanded resources, nationwide support, and end-to-end environmental solutions.
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CEMS probes are the first point of contact with the gas sample line in your emissions monitoring system. Discover why routine maintenance is critical—and how to do it right.