How is a mental disorder recognised as work-related, and what should companies prevent and correct?

In short: For a mental disorder to be recognised as work-related (a work-caused disease), three requirements must be met: (1) onset of a mental disorder covered by the recognition standard; (2) a strong work-related psychological burden in roughly the six months before onset; and (3) that onset cannot be attributed to non-work psychological burden or individual-side factors (Ministry of Health, Labour and Welfare, "Recognition standard for mental disorders caused by psychological burden," Notice Kihatsu 0901 No. 2 of 1 September 2023). The September 2023 revision added specific events such as customer harassment to the assessment table and reviewed the treatment of the work-causation of aggravation. A company has a position of cooperating with a workers'-compensation claim (cooperating with certification) and the separate safety-consideration duty under Article 5 of the Labor Contract Act. This article sets out, from a labour viewpoint, the recognition framework and what companies should prepare to prevent and correct.

"An employee is on leave for mental ill-health and says they are considering a workers'-compensation claim," and "we heard that power harassment and customer harassment can become work-related" — these are common questions from the owners and HR staff of small and medium enterprises. This page sets out the framework for recognising a mental disorder as work-related and what to put in place in work rules and the consultation structure to prevent and correct. Whether an individual case is work-related is finally decided by the labour standards inspection office, and disputes over damages for breach of the safety-consideration duty or over whether conduct amounts to harassment are the work of an attorney. This article focuses on what comes before that: the thinking behind the system and the design of the internal structure.

What are the three requirements for a mental disorder to be recognised as work-related?

Whether a mental disorder is recognised as work-related (a work-caused disease) is decided by the labour standards inspection office on the basis of the Ministry's recognition standard (Notice Kihatsu 0901 No. 2 of 1 September 2023). At its core are the following three requirements.

Requirement	Content
(1) Onset of a covered disease	Onset of a mental disorder covered by the recognition standard (ICD-10 F2–F4, etc.; broadly depression, acute stress reaction and the like)
(2) Strong work-related psychological burden	In roughly the six months before onset, a strong work-related psychological burden (an event assessed as "strong" on the table, etc.) is recognised
(3) Denial of non-work factors	It cannot be recognised that onset was caused by non-work psychological burden (private-life events) or individual-side factors (prior illness, alcohol dependence, etc.)

The basis for workers'-compensation benefits is the Workers' Accident Compensation Insurance Act; the kinds of insurance benefits are set out in Article 7, and the benefits for work accidents (medical treatment, leave, disability, survivors' benefits, and so on) in Article 12-8. A mental-disorder claim is structured so that work causation is recognised where the work-related psychological burden is assessed as "strong" and non-work and individual-side factors are denied. The procedure for returning from leave due to a private (non-work) illness — a separate track from workers' compensation — is set out in leave and return to work for mental ill-health.

How did the 2023 revision of the recognition standard change the assessment of events such as harassment?

The revision of 1 September 2023 (Notice Kihatsu 0901 No. 2) abolished the old 2011 standard and reviewed the assessment mechanism in light of the latest medical knowledge. The main changes relevant to company practice are as follows.

Point of revision	Content
Added specific events	Added to the work-related psychological-burden assessment table such events as "subjected to a markedly troublesome act by a customer, business partner, facility user, etc." (so-called customer harassment) and "engaged in work with a high risk of infectious disease, illness or accident"
Clarified harassment intensity	In light of the six types of power harassment, expanded the concrete examples of psychological-burden intensity ("strong," "medium," "weak")
Work-causation of aggravation	Reviewed so that, even without a special event within roughly six months after onset, where the disorder is aggravated by a strong work-related psychological burden, work causation is recognised for the aggravated portion
Streamlined collection of medical opinion	For cases that had required deliberation by three specialists, changed so that, except particularly difficult ones, a decision can be made on one specialist's opinion

What companies should grasp here is that customer harassment and troublesome acts by customers are now squarely subject to assessment as a work-related psychological burden. Keeping records of customer interactions and putting a consultation structure in place carries weight for both prevention and correction. Practical measures against customer harassment are set out in the obligation on customer-harassment measures and company preparation, and workplace power-harassment prevention measures in power-harassment prevention measures for small and medium enterprises. The final judgment on which intensity a particular event amounts to is made by the labour standards inspection office.

How does the duty to cooperate with a claim differ from the safety-consideration duty?

"Workers' compensation" and "damages" are separate systems. Because confusing them leads to a wrong response, understanding them by role is the premise.

Aspect	Cooperation with a workers'-compensation claim	Safety-consideration duty
Basis	Workers' Accident Compensation Insurance Act and its ordinance (employer certification, etc.)	Labor Contract Act, Article 5 (employer's safety-consideration duty)
Nature	The employer's certification of and cooperation with the worker's claim to the State (the inspection office)	The employer's civil-law duty to secure the life, body and so on of the worker
Effect	If recognised, benefits are paid from workers'-compensation insurance (not borne by the company)	If breached, liability in damages (borne by the company), claimable to the extent not overlapping with insurance benefits
Deciding party	Labour standards inspection office	Ultimately the court (including settlement and negotiation)

Workers'-compensation benefits, where work causation is recognised, are paid by the State and are not borne directly by the company. By contrast, where a mental disorder is caused in breach of the safety-consideration duty (Labor Contract Act, Article 5), the employer may, separately from insurance benefits, bear civil liability in damages. This is borne by the company and can be large. Cooperation with the claim procedure can be supported by a Shakai Hoken Roumushi, but claims for damages, settlement negotiations, and disputes over whether conduct amounts to harassment are the work of an attorney. For the split, see also consulting on dismissal and damages: the Shakai Hoken Roumushi or an attorney.

What should be prepared in work rules and the consultation structure for prevention and correction?

For both workers' compensation and damages, prevention imposes a smaller burden than responding after the fact. The main items a company should have in place are as follows.

Have a question about your situation?

Tell us about your social insurance, payroll or employment enquiry.

Chat on LINEContact us

Item	Content	Related system
Harassment prevention measures	Clarify and make known the policy; set up a consultation desk; respond appropriately to consultations. Mandatory for small and medium enterprises too from 1 April 2022	Act on Comprehensive Promotion of Labour Policies, Article 30-2 (duty of power-harassment prevention measures)
Clear consultation and reporting routes	Set out in work rules and internal regulations the consultation desk, the ban on detrimental treatment, and the fact-finding procedure	Work rules (Labor Standards Act, Article 89)
Curbing long working hours	Manage the overtime cap and keep objective attendance records; overwork is one element of a strong psychological burden	Objective grasp of working hours
Stress check	Early grasp of psychological burden; an expansion of coverage is planned	the expansion of the stress check to workplaces under 50

As for customer harassment, in light of its addition to the psychological-burden assessment in the 2023 revision, turning customer-interaction procedures into a manual and keeping records of responses leads to prevention. Putting these structures in place is the work of a Shakai Hoken Roumushi, who handles preparing work rules and harassment-prevention regulations, designing the operation of the consultation desk, and organising attendance management. The flow of the claim procedure when a case suspected of being work-related actually arises is set out in the workers'-compensation procedure for mental disorders and brain/heart disease.

How do you split consultations: the claim to the Shakai Hoken Roumushi, damages and harassment disputes to the attorney?

The situations around a mental-disorder workers'-compensation case divide by deciding party and by who handles them. It is reliable to consult by role.

What is done	Whose responsibility
Putting in order work rules and harassment-prevention regulations, designing the consultation structure, attendance management, supporting the claim procedure	Shakai Hoken Roumushi (this office)
Certifying whether an individual case is work-related (a work-caused disease)	Labour standards inspection office
Claims for damages for breach of the safety-consideration duty, settlement negotiation, disputes over whether conduct amounts to harassment	Attorney
Medical judgment on diagnosis, treatment and fitness for work	Attending physician / occupational physician

This office handles putting the structure in place for prevention and correction and supporting the claim procedure. Whether an individual case is recognised is decided by the labour standards inspection office, and damages and harassment disputes by an attorney, each from an independent position. Because a Shakai Hoken Roumushi cannot represent a damages claim or give legal advice, we connect you to an attorney for the dispute stage.

What can 四葉社会保険労務士事務所 do?

四葉社会保険労務士事務所, in Kohinata, Bunkyo City, handles putting work rules including harassment-prevention regulations in order, designing the operation of the consultation desk, designing attendance management that curbs long working hours, and supporting the workers'-compensation claim procedure. Together with the stress check and measures against power harassment and customer harassment, you can consult us, through a single point of contact, from prevention to correction. Consultation is free. For fees, see the fee schedule; for frequently asked questions, see the FAQ.

Frequently asked questions

Q. What is needed for a mental disorder to be recognised as work-related?
A. The three requirements must be met: (1) onset of a mental disorder covered by the recognition standard; (2) a strong work-related psychological burden in roughly the six months before onset; and (3) that onset was not caused by non-work factors or individual-side factors (Notice Kihatsu 0901 No. 2 of 1 September 2023). The final judgment on whether a case meets the requirements is made by the labour standards inspection office.

Q. Is customer harassment also subject to workers'-compensation assessment?
A. It can be. The September 2023 revision added "subjected to a markedly troublesome act by a customer, business partner, facility user, etc." as a specific event on the work-related psychological-burden assessment table. Which intensity it amounts to is assessed by the content and degree of the event, and the final judgment is made by the labour standards inspection office.

Q. If workers' compensation is recognised, does the company pay the compensation?
A. Workers'-compensation benefits are paid by the State and are not borne directly by the company. However, where there was a breach of the safety-consideration duty (Labor Contract Act, Article 5), the employer may, separately from insurance benefits, bear civil liability in damages. That claim and negotiation are the work of an attorney.

Q. What should we put in place first for prevention?
A. As harassment prevention measures (Act on Comprehensive Promotion of Labour Policies, Article 30-2; mandatory for small and medium enterprises too from 1 April 2022), making the policy known, setting up a consultation desk, and arranging appropriate responses are the starting point. Together with that, setting out the consultation route in work rules, attendance management that curbs long working hours, and early grasp through the stress check are effective.

Sources

• Workers' Accident Compensation Insurance Act (Act No. 50 of 1947), Article 7 (kinds of insurance benefits), Article 12-8 (benefits for work accidents = medical-treatment, leave, disability and survivors' benefits, etc.)
• Ministry of Health, Labour and Welfare, "Recognition standard for mental disorders caused by psychological burden," Notice Kihatsu 0901 No. 2 of 1 September 2023 (abolishing Notice Kihatsu 1226 No. 1 of 26 December 2011; the three recognition requirements, the work-related psychological-burden assessment table, the addition of specific events such as customer harassment, the review of the work-causation of aggravation, and the streamlining of medical-opinion collection)
• Act on Comprehensive Promotion of Labour Policies and Stabilisation of Employment of Workers, etc., Article 30-2 (duty of power-harassment prevention measures; fully in force for small and medium enterprises from 1 April 2022)
• Labor Contract Act (Act No. 128 of 2007), Article 5 (employer's safety-consideration duty)
• The classification of covered diseases under the recognition standard, the wording of the three requirements, and the added specific events are confirmed from materials published by the Ministry of Health, Labour and Welfare (the standard text and leaflets) (as of October 2026). This article does not judge which intensity a particular event amounts to

This article does not decide whom to consult. Putting in order work rules and harassment-prevention regulations, designing the consultation structure, attendance management, and supporting the workers'-compensation claim procedure are the work of a Shakai Hoken Roumushi. Whether an individual case is work-related is certified by the labour standards inspection office; damages for breach of the safety-consideration duty and disputes over harassment are handled by an attorney; and medical judgment by the attending physician / occupational physician — each from an independent position. For fees when consulting 四葉社会保険労務士事務所, see the fee schedule; for frequently asked questions, see the FAQ.

This article is general information. A judgment on individual circumstances is made by a qualified professional after a consultation. Written by Joji Uramatsu (Shakai Hoken Roumushi, Gyoseishoshi, Registered Real Estate Transaction Specialist).