Scientific Technologies Inc After introducing its first infrared solid-state proximity photoelectric control more than 30 years ago, Scientific Technologies Inc has grown to be a leading supplier of machine safeguarding products in the USA and is recognised throughout the world for its high-quality products and services. STI products are used to keep people safe while automated factories produce a variety of complex and important products such as automobiles, computers, electronics, and food and beverages. STI safety products include safety light curtains, interlocks, relays, mats and sensors.