Technical Japanese #14 — Safety Japanese: KY, Near Miss and 5S in a Japanese Factory
In a Japanese plant, 安全 (anzen) sits above output and above quality. 「安全第一」 is not a slogan on a wall. What distinguishes Japanese safety practice is that it is actively preventive: the hazard is predicted before it becomes real. This post unpacks the three pillars — 危険予知 (KY), ヒヤリハット and 5S — and the vocabulary that travels with them.
The three pillars of preventive safety
- 危険予知 (kiken yochi, KY) — naming the hazards of the job you are about to do. Many sites run KYT (危険予知訓練) at the start of the shift: what could go wrong today, and how do we prevent it?
- ヒヤリハット — the near miss, the moment that gave you a fright without causing injury. Every serious accident is preceded by hundreds of them (the Heinrich triangle), so the more that get reported, the better the chance of stopping the real one.
- 5S — 整理 sort, 整頓 set in order, 清掃 clean, 清潔 standardise, 躾 sustain as a habit. A tidy workplace means fewer trips, fewer trapped hands, and abnormalities that are easy to see.
Core safety vocabulary
| Japanese | Reading | Meaning | Field note |
|---|
| 安全 | あんぜん anzen | safety | As in 安全第一, safety first |
| 危険予知 | きけんよち kiken yochi | hazard prediction (KY) | The start-of-shift activity |
| ヒヤリハット | hiyari hatto | near miss | Reported so it can be prevented |
| 労働災害 | ろうどうさいがい rōdō saigai | industrial accident | Shortened to 労災 rōsai |
| 怪我 | けが kega | injury | Being hurt |
| 保護具 | ほごぐ hogogu | protective equipment | Helmet, glasses, gloves, boots |
| 指差呼称 | ゆびさしこしょう yubisashi koshō | point-and-call | Point at it and say it aloud to confirm |
| 整理 | せいり seiri | sort | 5S — remove what is not needed |
| 整頓 | せいとん seiton | set in order | 5S — a place for everything |
| 清掃 | せいそう seisō | shine | 5S — cleaning |
| 清潔 | せいけつ seiketsu | standardise | 5S — keep the first three going |
| 躾 | しつけ shitsuke | sustain | 5S — make it a habit |
| ゼロ災 | zero-sai | zero accidents | The target is zero |
指差呼称 — pointing and calling
When confirming something that matters, the operator points at the object and says it out loud — point at the pressure gauge and call 圧力よし！ (pressure, OK). Eye, hand, voice and brain all confirm the same thing at the same moment, and errors of inattention drop sharply. If you are asked to do it, do it properly. It is part of 躾.
The four rounds of KYT, and the ゼロ災 target
- 現状把握 — grasp the situation: what hazards are hidden here?
- 本質追求 — find the essence: pick the most serious one.
- 対策樹立 — build the countermeasure: propose something concrete.
- 目標設定 — set the target: agree one focus action and call it out together.
The goal is ゼロ災, zero accidents. Cutting in at the base of the Heinrich triangle — by reporting ヒヤリハット — is the cheapest and most effective way to get there.
保護具 (protective equipment) and machine lockout (LOTO)
| Japanese | Reading | Meaning |
|---|
| 保護帽 / ヘルメット | ほごぼう hogobō / herumetto | safety helmet |
| 保護メガネ | ほごメガネ hogo megane | safety glasses |
| 手袋 | てぶくろ tebukuro | gloves |
| 安全靴 | あんぜんぐつ anzengutsu | safety boots |
| 耳栓 | みみせん mimisen | ear plugs |
| マスク | masuku | mask |
LOTO (ロックアウト・タグアウト): lock off the energy source and hang your own tag before your hands go into the machine, and only the person who fitted the lock may remove it. If you find a machine stopped with a lock, a tag or a 点検中 sign, never restore power — however sure you are that the work is finished.
Sentences from the floor
- 安全第一で作業してください。 — Work with safety first.
- ヒヤリハットがありました。報告します。 — I had a near miss. I am reporting it.
- 保護具を着用してください。 — Please wear your protective equipment.
- 危ない！止まってください。 — Danger! Stop.
- 作業前にKYをやりましょう。 — Let us do the KY before we start.
Mistakes to avoid
| Mistake | Why it hurts |
|---|
| Not reporting a ヒヤリハット because "nothing happened" | It is the most valuable warning signal there is — hiding it throws away the chance to prevent a real accident |
| Treating 5S as tidying up for appearances | Drop 整頓 and tools scatter: trips, trapped fingers, wasted time |
| Going through the motions of 指差呼称 | It works because you look, point and speak clearly. Performed emptily it does nothing |
| Skipping the KY meeting at the start of the shift | You then work without knowing the risks that were already identified |
See it, then react — quick self-check
- Your hand was nearly trapped, but nothing happened.
- You hear 危ない！ behind you.
- You find a stopped machine with a LOTO tag.
- Tools are left scattered at the end of the shift.
<details><summary>Answers</summary>
- Report the ヒヤリハット. It is valued behaviour, not an admission of fault.
- Stop and look around first; ask why afterwards.
- Do not restore power. Only the person who fitted the lock may remove it.
- Do 整頓. Safety starts at your own bench.
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Quick recall
- Three pillars: KY to predict, ヒヤリハット to report, 5S to keep the place readable.
- Do 指差呼称 properly; run the four rounds of KYT at the start of the shift; aim at ゼロ災.
- LOTO: only the person who locked it removes it. Three phrases that save people: 危ない！ 止めて！ 離れて！
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Next in the series: reading safety signs · 保全 maintenance · how to ask again when you did not understand.
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