The ATEX-certified mechanical handheld tachometer from Rheintacho has received Class I approval for Zone 1 applications in mining. The HTM has been further developed and certified for use in ATEX zones 1 and 2 and for use in all gas groups with temperature class T4. For mining applications, the use is intended for short-term monitoring and measurement, not for continuous operation. The tachometer measures rotational speeds and surface speeds using specially provided contact adapters. Recognizable by its ergonomic design, the ATEX device is available in four models.