Construction Safety in Japan: The Rules You’ll Actually Meet

Chapter 04

Working at Height

Falls are the reason for a large part of the rulebook, so the details here are specific. These are the ones you’d actually notice.

The scaffold platform itself

Where a scaffold has a work platform (other than a suspended scaffold), the Ordinance sets dimensions:

• The platform must be 40 cm wide or more
• Gaps between floor boards must be 3 cm or less
• The gap between the floor boards and the standards (uprights) must be **less than 12 cm**

Where someone could fall, the platform needs fall-prevention equipment — for frame scaffolds, cross bracing plus a rail 15–40 cm high or a toe board at least 15 cm high, or a handrail frame; for other scaffolds, a guardrail plus an intermediate rail.

And where objects could fall on people, toe boards at least 10 cm high, mesh sheets or safety nets (or equivalent), with limited exceptions.

Source: Ordinance on Industrial Safety and Health, Article 563 (e-Gov, in Japanese), checked September 20, 2026

Access routes

Temporary access routes have their own rules:

• Slope of 30 degrees or less (unless it’s stairs, or under 2 m with a sturdy handhold)
• Over 15 degrees, cleats or other anti-slip measures
• Where there’s a fall risk: a guardrail 85 cm or higher, plus an intermediate rail between 35 and 50 cm
• Ramps of 8 m or more used in construction work need a landing every 7 m

Source: Ordinance on Industrial Safety and Health, Article 552 (e-Gov, in Japanese), checked September 20, 2026

Taking a handrail off

This is the detail I’d most want a visitor to understand, because it’s where sites in different countries diverge most.

If the work genuinely requires the guardrail or intermediate rail to be removed temporarily, the exemption only applies when both of these are done:

1. Equipment is provided to safely attach fall arrest devices, and workers actually use them (or an equally effective measure is taken)
2. Everyone not involved in that work is prohibited from entering, with a notice displayed where it can be seen, or by another method

So removing a handrail isn’t a decision one person makes and quietly reverses later. It comes with an attachment point, a used harness, a barrier and a sign.

Source: Ordinance on Industrial Safety and Health, Article 552, paragraph 2 (e-Gov, in Japanese), checked September 20, 2026

Scaffold inspections

Two layers, and both show up in daily life on site.

Before work starts each day, the employer must name an inspector to check whether the scaffold’s fall-prevention equipment has been removed or has come off, and repair anything wrong immediately.

After bad weather — strong wind, heavy rain, heavy snow — or an earthquake of medium intensity or above, or after the scaffold has been assembled, partly dismantled or altered, a fuller inspection is required before work: floor boards, connections, fittings, toe boards, settlement and sliding of the base, bracing, damage to members, and so on. The result, the inspector’s name, and any repairs must be recorded and kept until the work using that scaffold is finished.

Source: Ordinance on Industrial Safety and Health, Article 567 (e-Gov, in Japanese), checked September 20, 2026

If you’ve ever wondered why the morning after a typhoon is slow on a Japanese site, this is why. Nobody is being cautious for the sake of it — the inspection is required before work restarts.

Chapter 05

Heat: The Newest Rule

If you take one current thing from this article, take this one. It changed recently, and a lot of English-language material hasn’t caught up.

What changed

An amendment to the Ordinance on Industrial Safety and Health came into effect on June 1, 2025, turning workplace heatstroke measures into a legal duty.

Japan’s summers are genuinely dangerous for outdoor work, and construction is one of the most affected industries. The ministry’s own framing is that most fatal cases come down to early symptoms being missed, or the response coming too late — so the new duties are aimed squarely at those two failures.

Which work it applies to

According to the ministry’s guidance, the measures apply to work expected to be carried out:

• continuously for 1 hour or more, or
• for more than 4 hours in a day

in an environment with a WBGT of 28°C or higher, or a temperature of 31°C or higher.

Source: Ministry of Health, Labour and Welfare, “Strengthening of Measures against Heatstroke in the Workplace” (leaflet, in English), checked September 20, 2026

WBGT is the “wet bulb globe temperature” — a heat index that accounts for humidity, radiant heat and air movement, not just air temperature. On a Japanese site in August, you’ll see it posted somewhere near the gate.

What employers must actually do

The new article of the Ordinance sets out two duties, and both end with telling the workers about it.

1. A system for reporting. Before the work starts, the employer must set up a system so that a worker who has symptoms of heatstroke — or who finds another worker they suspect has heatstroke — can report it. Workers must be told how that system works.

2. Procedures for stopping it getting worse. Again in advance, and for each workplace, the employer must decide the measures and the procedure for carrying them out: removing the person from the work, cooling their body, and arranging medical examination or treatment where necessary. Workers must be told those procedures too.

Source: Ordinance on Industrial Safety and Health, Article 612-2 (e-Gov, in Japanese), checked September 20, 2026

Why the “report someone else” part matters

Read duty 1 again: it covers the worker who notices someone else in trouble.

That’s the part I’d underline. Heatstroke makes people poor judges of their own condition — the person who most needs to stop is often the last to say so. Making “I think he’s not right” a reportable thing, with a route to report it, is aimed exactly at that.

What it looks like on site

In practice you’ll see some combination of: WBGT posted daily, water and salt tablets available, a shaded or air-conditioned rest space, work rescheduled to the cooler hours, fan jackets and cooling vests, and a named person to tell.

Also more breaks. The 10:00 and 15:00 breaks I described in a day on a Japanese construction site are the baseline. In real heat, sites add to them.

Chapter 06

The Daily Controls

These are the ones you meet constantly — the small controls that shape how people move around a site.

Keeping people away from machines

Where construction machinery is operating, the employer must prohibit workers from entering any area where contact with the moving machine could be dangerous, with a notice displayed where it can be seen or by another method.

There’s one exception, and it’s specific: it doesn’t apply when a guide is posted to direct the machine. In that case the operator must follow the guide’s direction, and where a guide is posted, set signals must be decided and used — with the operator required to follow them.

Source: Ordinance on Industrial Safety and Health, Articles 158 and 159 (e-Gov, in Japanese), checked September 20, 2026

This is why an excavator working near people on a Japanese site usually has someone standing with it whose only job is directing. That person isn’t spare labour. They’re the legal condition that allows the work to happen at all.

Leaving the cab

When an operator leaves the operating position, they must lower the bucket or other working device to the ground, and stop the engine and apply the brake or otherwise prevent the machine running away. The duty is written twice — once on the employer to have it done, once on the operator to do it.

Source: Ordinance on Industrial Safety and Health, Article 160 (e-Gov, in Japanese), checked September 20, 2026

Exclusion zones in general

You’ll see a lot of rope, cones, tape and signs. The pattern repeats across the rules: where a hazard can’t be removed, the answer is to keep people out of the area and say so visibly.

Two you’ll meet often: not standing under a suspended load, and not entering the area below overhead work. If you see a barrier with a sign on a Japanese site, treat it as a rule rather than a suggestion — someone wrote it because a specific regulation required them to.

Permits, before certain work

Beyond the Ordinance, most sites run their own permit system for work that is hazardous or affects everyone else: hot works, work on live electrical installations, lifting operations, entry into confined spaces, work outside normal hours.

These aren’t universal law — they’re the site’s own control, agreed at the foremen’s meeting and written into the day’s work request sheets. Ask before you assume something is allowed.

And the qualification check

Machinery work, lifting, and many other tasks can only be done by someone with the right licence or completed skill training, who is carrying the certificate (chapter 2).

In practice this is checked. If your certificate is in a drawer at home, expect to be told to stop — not because anyone doubts you, but because the person telling you is under a legal duty to correct what they’ve seen.

Chapter 07

When Something Goes Wrong

The first minutes

The response is the same anywhere: look after the person, make the area safe so nobody else gets hurt, call for help, and tell the site management immediately.

What’s specific to Japan is how fast the second part happens. Work in the affected area stops, and it usually doesn’t restart that day. Nobody has to approve that decision in advance — it’s the expected response.

Reporting is a legal duty, not a company decision

Two separate reporting duties sit in the Ordinance.

Accidents involving certain equipment or structures. Fires and explosions, the collapse of a building or structure, a crane overturning or dropping its load, a wire rope or chain breaking, and similar events must be reported without delay to the head of the competent Labour Standards Inspection Office.

Injuries to workers. Where a worker dies or has to take time off work because of a work injury, the employer must report it without delay, through the electronic reporting system, to the same office.

Source: Ordinance on Industrial Safety and Health, Articles 96 and 97 (e-Gov, in Japanese), checked September 20, 2026

One detail in that second duty says a lot about how Japanese construction works. When the injured person is a subcontractor’s worker on a construction project, the report includes the principal employer’s labour insurance number and the name of the project.

The general contractor is in the paperwork, whoever the person worked for. That’s the same principle as chapter 1, showing up at the worst possible moment.

What happens next on site

From what I’ve seen, the pattern is consistent.

• Work in that area stays stopped until the cause is understood.
• The site investigates — what happened, why, and what would have prevented it. The foremen are part of that, not just the main contractor.
• The method changes, and the change is written into the work procedure rather than just announced.
• It gets shared. Other sites in the same company hear about it. A near miss at one site turns into a briefing point at another.

Near misses count

One thing I’d encourage anyone joining a Japanese site to take seriously: the near miss report — hiyari hatto, from the words for “startled” and “gasped.”

It’s the thing that nearly happened. Nobody was hurt, so there’s nothing to report legally, and it would be easy to say nothing.

Sites collect them anyway, because the near miss and the accident usually have the same cause — and the near miss is the free version of the lesson.

The honest part

Accidents still happen. Japan has a detailed rulebook and a strong safety culture, and people are still injured on Japanese sites every year.

Rules reduce risk. They don’t remove it, and anyone who tells you their site is completely safe has stopped paying attention. The value of a system like this isn’t perfection — it’s that when something does go wrong, it’s much harder for it to be quietly repeated somewhere else.