Third Schedule explained: this guide covers what it means, who it applies to, the step-by-step process, documents required, fees, due dates and penalties in India — so you can stay compliant with confidence and avoid costly mistakes.
The Third Schedule is the Code's list of occupational diseases. Section 2(51) defines an "occupational disease" as a disease specified in this Schedule, and the list drives compensation under Chapter VII, medical board references and the ESI provisions on occupational disease.
A disease counts as an occupational disease under the Code only if it is specified in the Third Schedule (s.2(51)). The Schedule has three Parts: Part A (5 items), Part B (27 items) and Part C (6 items). For most items the employment is stated as "all work involving exposure to the risk concerned". Under s.74(1), an employer is liable to compensate injury caused by an occupational disease listed in the Third Schedule arising out of and in the course of employment; s.74(3) treats a disease peculiar to a Second Schedule employment as an accident after six months' continuous service. The Government can only add to the list (s.152(2)).
Why it matters
Employers in chemical, mining, construction, manufacturing, healthcare and laboratory work should know which diseases are listed and how compensation arises. An unlisted disease does not qualify as "occupational disease" for these provisions, though an injury by accident may still be compensable under s.74. For advice on insurance cover, records of exposure and claims handling, see our labour law compliance service. The list pairs with the Second Schedule, which lists the employments, and with sections 36 and 37 on occupational diseases and medical boards.
Where the Schedule is used
| Provision | Use |
|---|---|
| s.2(51) | Defines "occupational disease" by reference to this Schedule |
| s.36(1) | ESI provision on occupational disease (continuous period set by ESIC regulations; see our article on sections 36 and 37) |
| s.74(1) | Employer's liability for injury by accident or an occupational disease listed in the Third Schedule arising out of and in the course of employment |
| s.74(3) | Disease peculiar to a Second Schedule employment, contracted after six months' continuous service, deemed an injury by accident and presumed to arise out of and in the course of employment unless the contrary is proved |
| s.74(5) | Government may add after three months' notice and specify the diseases peculiar to added employments |
| s.131(5) and s.132 | Named in the Schedule's heading for other purposes |
| s.152(2) | Appropriate Government may add to the Schedule, not delete |
The three Parts
Part A (5 items)
- Infectious and parasitic diseases contracted in an occupation with a particular risk of contamination: employment covers all work involving exposure to health or laboratory work; veterinary work; handling animals, carcasses or contaminated merchandise; and other work carrying a particular risk of contamination.
- Diseases caused by work in compressed air.
- Diseases caused by lead or its toxic compounds.
- Poisoning by nitrous fumes.
- Poisoning by organo phosphorus compounds.
Items 2 to 5 cover "all work involving exposure to the risk concerned".
Part B (27 items)
Part B lists chemical, physical and biological causes. Representative entries:
| Group | Items (serial number in Part B) |
|---|---|
| Metals and compounds | Phosphorus (1), mercury (2), chromium (5), arsenic (6), manganese (12), beryllium (16), cadmium (17), fluorine (19) |
| Organic chemicals | Benzene and homologues (3), nitro and amido derivatives of benzene (4), halogen derivatives of hydrocarbons (9), carbon disulphide (10), dinitrophenol (15), nitroglycerin and nitroacid esters (20), alcohols and ketones (21), asphyxiants including carbon monoxide and hydrogen sulphide (22) |
| Radiation | Radioactive substances and ionising radiations (7); occupational cataract due to infra-red radiations (11) |
| Cancers | Primary epitheliomatous cancer of the skin from tar, pitch, bitumen, mineral oil, anthracene and their products (8); lung cancer and mesotheliomas caused by asbestos (23); primary neoplasm of the epithelial lining of the urinary bladder, kidney or ureter (24) |
| Skin, hearing, breathing | Skin diseases from physical, chemical or biological agents not included elsewhere (13); hearing impairment caused by noise (14); occupational asthma from recognised sensitising agents (18) |
| Climate | Snow blindness in snow-bound areas (25); effects of heat in extreme hot climate (26); effects of cold in extreme cold climate (27) |
For Part B the employment column is "all work involving exposure to the risk concerned"; for radiation (item 7) it is all work involving exposure to the action of radioactive substances or ionising radiations.
Part C (6 items)
- Pneumoconioses caused by sclerogenic mineral dust (silicoses, anthracosilicosis, asbestosis) and silico-tuberculosis, provided that silicosis is an essential factor in causing the resultant incapacity or death.
- Bagassosis.
- Bronchopulmonary diseases caused by cotton, flax, hemp and sisal dust (byssinosis).
- Extrinsic allergic alveolitis caused by inhaling organic dusts.
- Bronchopulmonary diseases caused by hard metals.
- Acute pulmonary oedema of high altitude.
The scan has some garbled spellings in Part C; the items above follow what is readable. Part C entries carry the same employment column, "all work involving exposure to the risk concerned".
The Code does not attach different legal consequences to Parts A, B and C in the text we read; all three Parts are the list referred to in s.2(51).
How compensation links to the list
- For any employee, an occupational disease in the Schedule is a ground for liability under s.74(1) if it arises out of and in the course of employment.
- For an employee in a Second Schedule employment, s.74(3) gives a presumption after six months of continuous service with the employer.
- Amounts and procedure are in section 76. Chapter VII applies where Chapter IV (ESI) does not; where ESI applies, see the ESI benefits provisions.
A worked example
A worker in a battery plant is diagnosed with a disease caused by lead, a Part A item, after working there for over a year. He is an employee for Chapter VII if the plant's work is in the Second Schedule (such as a factory with a manufacturing process using power) and Chapter IV does not apply. Since he has served more than six months, s.74(3) deems the disease an injury by accident and presumes that it arose out of and in the course of employment unless the employer proves otherwise. (Illustrative; the amount and procedure follow Chapter VII.)
Need help with occupational disease exposure?
Good exposure records, medical surveillance and adequate insurance reduce disputes. Our labour law compliance team can help you map your processes to the Third Schedule, set up records and review your compensation readiness.
Key takeaways
- Only diseases in the Third Schedule are "occupational diseases" (s.2(51)).
- Part A: 5 items; Part B: 27 items; Part C: 6 items.
- Most entries cover all work involving exposure to the risk concerned.
- Section 74(3): six months' continuous service gives a presumption for Second Schedule employments.
- The Government can add diseases (after three months' notice), not delete.
Read next
- Second Schedule: Employees covered for compensation
- Fourth Schedule: Injuries and disablement
- Sections 36 and 37: Occupational diseases and references to Medical Board
- Disability benefit under ESI: temporary and permanent
Disclaimer: Based on the Code on Social Security, 2020 (as enacted) and, where noted, the Code on Social Security (Central) Rules, 2026 (G.S.R. 344(E), 8 May 2026), as on 30 September 2026. The Code is in force from 21 November 2025; some provisions may be notified later, and State Governments make their own rules for establishments where the State is the appropriate Government. Verify the current position before acting.