Updated Aug 28, 2026 · v9.43.0
The definitive version of the Otsu 4 countermeasure app! 618 frequently asked questions ranging from basic Q&A to the actual format. If you want to take Hazardous Materials Handler Otsu 4, install it now!
The definitive app for studying for the Class B Hazardous Materials Handler License, Category 4 (Otsu-yon)! From basic Q&A to exam-style questions, it features 618 frequently asked questions. All questions include detailed explanations. There's also a function to review checked questions later. Don't miss the "Hazardous Materials Class B-4 Study Method" page, which provides detailed explanations on how to study for the Hazardous Materials Class B-4 exam! This app, "Hazardous Materials Class B-4 Complete Question Explanation - Self-Study TODAY," is free to use. If you are concerned about advertisements, we apologize, but please consider the paid "Serious Study Plan (Ad-Free)." Terms of Use: https://apps.trips.co.jp/terms_of_use.html If you notice any bugs or issues, please feel free to contact us through the in-app inquiry form. This app, "Hazardous Materials Class B, Category 4: Complete Question Explanation - Self-Study TODAY - 618 Frequently Asked Questions from Basic Q&A to Exam Format," is part of the "Self-Study TODAY" series, a trusted and proven qualification exam preparation app with over 10 million downloads. A powerful ally for qualification acquisition and exam preparation. If you want to obtain the national qualification "Class B, Category 4 Hazardous Materials Handler," install this popular free app now!
5 years on Google Play
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