Explosives Safety Exam A JP

A study app for Japan's Class A Explosives Handling Safety Supervisor exam (甲種火薬類取扱保安責任者試験). This national qualification is based on the Explosives Control Act. A safety supervisor must be appointed by anyone who owns or occupies an explosives magazine, or who consumes explosives. The Class A licence applies to magazines storing 20 tonnes or more of explosives per year, and sites consuming 1 tonne or more per month; it carries no upper limit and also covers Class B work. All 350 practice questions come with a clear explanation.

■ Subjects Covered (350 questions across 2 subjects, 10 areas)

【Law - Explosives Control Act and related regulations (20 questions in the exam)】
• General provisions, definitions, manufacture, sale, transfer and import (42)
• Storage and explosives magazines (46) - permits, inspections, magazine types, maximum quantities
• Transport, consumption and disposal (46) - notifications, transport certificates, exempt quantities
• Handling, safety training, supervisors, records and penalties (30)
• Quantity calculations (17) - conversion to explosive equivalent, maximum storage for class 1 and class 2 magazines, safety distances

【General Explosives Science (20 questions in the exam)】
• Classification, composition and properties (37) - deflagration and detonation, oxygen balance, black powder, smokeless powder, ANFO, water gel
• Explosion phenomena, sensitivity, performance tests and stability (37) - force of powder, power and brisance, detonation pressure, sympathetic detonation, dead pressing
• Pyrotechnic devices - detonators, safety fuse, detonating cord (38) - electric detonators, DS and MS detonators, delay blasting
• Blasting methods, electric blasting and safety (35) - free face and burden, crater index, blasting coefficient, bench blasting, controlled blasting
• Blasting calculations and force of powder (22) - Hauser's formula, crater radius, bench blasting, firing circuits

The exam is administered by prefectural governors once a year at venues in each prefecture. The Class A paper has 40 questions in total - 20 on law and 20 on general explosives science - and you need at least 60% in each subject to pass. The biggest difference from Class B is the weight given to calculations: determining maximum storage by explosive equivalent, and working out charge weights with Hauser's formula. This app separates the calculation areas out as "Law 5" and "General Explosives Science 5", with 39 questions between them. The explanations build each formula step by step, so you learn how to solve the problems rather than memorising equations.

The law section rewards accurate recall of figures and procedures, making it the most reliable place to score. This app splits each subject into five areas, so you can drill the easily confused figures - maximum storage quantities, exempt transport quantities, safety distances - area by area, with accuracy tracked automatically. There are no eligibility requirements: anyone can sit the exam. The licence is issued by the prefectural governor once you pass.

■ Study Modes
• Random practice (10 / 25 / 50 / 100 questions)
• Study by subject
• All questions in order (resume supported)
• Review incorrect answers
• Bookmarks and unanswered questions

■ Progress Tracking
• Automatic tracking of correct answer rate
• Area-by-area performance overview - essential when each subject has its own minimum score

Works completely offline - study anytime, anywhere.

■ Reference Sources
• https://www.zenkakyo-ex.or.jp/ (Japan Explosives Safety Association)
• https://www.meti.go.jp/ (Ministry of Economy, Trade and Industry)

※ This app is an independent study tool and is not affiliated with any examination body. Content is based on the general scope of the exam and may differ from the actual exam due to legal updates.