From Otsu-4 to all six Otsu classes
Hazardous Materials, Otsu (incl. Otsu-4)
Practice only what your selected class requires.
Covers Otsu classes 1–6, combining shared knowledge with class-specific questions for standard and exempted exam formats.
Classes 1–6280 questions per selected classStandard and exempted mocks
680 questions total
3-MINUTE CHECK
Try three questions.
Can you recall the reason?
The mini diagnostic is in Japanese, with a short explanation after each answer. No sign-up is required.
QUESTION 1 / 3
第4類（引火性液体）の性質として、消防庁の概要と一致するものはどれか。
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