Otsu-4 Anki Club: Kiken-butsu

The Otsu-4 (乙4) hazardous-materials handler exam trainer for Japan — the license that raises hourly wages at gas stations and warehouses across Japan. • 911 original drill questions with explanations (regulations / physics & chemistry / properties & firefighting) — real count, no inflated numbers • 26 original Japanese mnemonics (goro) for designated quantities and key facts • Full-format mock exam: 35 questions, 2-hour timer, graded with the real rule — 60% or better in every subject • Leitner spaced repetition brings back exactly what you were about to forget • Reference table of 30 Class-4 substances: quantities, flash points, solubility, extinguishing agents • Study features work fully offline, including in airplane mode — no account or internet needed to learn A banner appears at the bottom of the screen, and a full-screen ad may appear at natural breaks. An optional one-time "Remove Ads" purchase hides both. Note: exam content is in Japanese (the exam itself is administered in Japanese). Original study material, not a copy of any commercial past-question book. Interface available in English, Japanese and Simplified Chinese.