| Year | Detail |
|---|
| 1961 |
TSI Inc. was founded in 1961 as Thermo-Systems Engineering Co. by Mike Fingerson. It was headquartered in a storefront on Hennepin Avenue in Minneapolis, Minnesota. |
| 2005 |
TSI acquired instrument-production lines owned by Airflow Developments Ltd., of High Wycombe, England. |
| 2008 |
TSI acquired Adams Instruments, certain assets of Mesacon GmbH, Facility Monitoring Systems, Ltd. of Malvern, England, and SystemPlus Technology Pte Ltd. of Singapore. |
| 2012 |
TSI acquired the laser induced breakdown spectroscopy (LIBS) technology and product line from Photon Machines Corporation of Redmond, Washington. |
| 2018 |
TSI acquired Quest Personal Safety Division products, including Dosimeters, EVM Environmental Monitors, Heat Stress Monitors, and Sound Level Meters from 3M. |
| 2022 |
TSI acquired Casella, a designer and manufacturer of innovative instruments and systems for occupational health, industrial hygiene, the outdoor environment, and the workplace. |
| 2024 |
TSI launched PRE Challenge Wafers designed to optimize particle removal efficiency (PRE) in semiconductor manufacturing. |
