危険物乙４（おつよん）全問解説 - 分野別一問一答と過去問

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 preparing for the Class 4 Hazardous Materials Handler Exam! It features 618 frequently asked questions, from basic Q&A to actual exam format.

Each question comes with a detailed explanation. There's also a feature that allows you to review all checked questions at once later.

Additionally, the "Study Methods for Hazardous Materials Class 4" page, which provides detailed instructions on how to study for the Hazardous Materials Class 4 exam, is a must-read. Please make use of it!

This app is compliant with legal changes as of April 2025 (Reiwa 7). Please use it with confidence.

All content in this app, "Hazardous Materials Class 4 (Otsuyon) All Questions and Explanations," is free to use.

If you are bothered by ads, please use the "Serious Study Plan (Ad-Free)." We apologize for the inconvenience, but if you prefer, please use the "Serious Study Plan (Ad-Free)."

Terms of Use: https://apps.trips.co.jp/terms_of_use.html

If you notice any issues, please feel free to contact us via the in-app inquiry form.

This app, "Hazardous Materials Handling Exam Class 4 (Otsuyon) - 618 Frequently Asked Questions from Basic Question-and-Answer to Full-Scale Exam Questions," is part of the "Dokugaku TODAY" series of exam preparation apps, a trusted and proven certification exam prep app with a total of 10 million downloads. It's a powerful ally for qualification acquisition and exam study. If you're planning to pass the Hazardous Materials Handling Exam Class 4, install this popular free app now!