JIS B 7023:2021 PDF Download

The classification and performance specifications for divers' timepieces used for deep diving are provided by JIS B 7023:2021. These watches must include a dive time measurement system that is visible in the dark and are especially made to endure diving in water that is at least 100 meters deep. Skin diving watches are exempt from the standard.

The fact that this standard is compatible with the related International Standard ISO 6425:2018, "Horology: Divers' Watches," should not be overlooked. According to ISO/IEC Guide 21-1, symbols like IDT (identical), MOD (modified), or NEQ (not equivalent) are used to indicate how closely the JIS standard and the ISO standard coincide.