MSIHC Rules 1989: Threshold Quantities & MAH Site Classification

The Manufacture, Storage and Import of Hazardous Chemical Rules, 1989 ('MSIHC Rules') classify a site as a Major Accident Hazard (MAH) installation when any hazardous chemical is held at or above the threshold quantities prescribed in Schedule 2 (isolated storage) or Schedule 3 (industrial activities). MAH occupiers owe six cumulative duties: hazard identification under Rule 4, 48-hour notification of major accidents under Rule 5, site notification 90 days before commencement under Rule 7, a safety report with independent audit under Rule 10, an on-site emergency plan with six-monthly drills under Rule 13, and continuous Public Liability Insurance under the PLI Act 1991.

TL;DR for factory occupiers and founders

If your factory, warehouse, pipeline, or port-side storage handles more than the Schedule 2 or Schedule 3 threshold quantity of any listed hazardous chemical — for example, 10 tonnes of chlorine, 60 tonnes of ammonia, 150 kg of methyl isocyanate, or 750 kg of phosgene — you are an MAH installation under Rule 2(ja) MSIHC Rules 1989. You have 48 hours to notify any major accident, 90 days pre-commencement for site notification, six-monthly on-site emergency drills, and an unbroken PLI policy. Penalty for default is prosecution under Sections 15-17 Environment (Protection) Act 1986: imprisonment up to five years and fine up to ₹1 lakh, rising to ₹5,000/day for continuing contravention.

What the MSIHC Rules cover

MSIHC Rules 1989 are delegated legislation notified under Sections 6, 8, and 25 of the Environment (Protection) Act, 1986 ('EP Act'). They operationalise India's post-Bhopal industrial-safety regime by prescribing: (i) a list of hazardous chemicals by name and by hazard class (Schedules 1-3); (ii) threshold quantities above which enhanced duties apply; (iii) a chain of reporting obligations from hazard identification through accident notification; (iv) on-site and off-site emergency planning; and (v) public information duties under Rule 15.

The Rules' rule-making power under the EP Act makes them enforceable as if part of the parent statute — contravention attracts the EP Act's criminal penalties, not a separate MSIHC penalty. The Rules have been amended four times since notification: S.O. 115(E) dated 5 February 1990, G.S.R. 584 dated 9 September 1990, S.O. 2882 dated 3 October 1994, and S.O. 57(E) dated 19 January 2000. The 1994 amendment introduced the "MAH installation" definition at Rule 2(ja); the 2000 amendment revised the Part I flammability criteria and the Schedule 2 threshold table.

The MSIHC framework sits alongside — and does not replace — the Factories Act 1948, the Hazardous and Other Wastes (Management and Transboundary Movement) Rules 2016, the Environment (Protection) Rules 1989 (including the Chemical Accidents (Emergency Planning, Preparedness and Response) Rules 1996 ('EPPR')), and the Public Liability Insurance Act 1991. An MAH site is typically regulated under several of these in parallel. The Central Government retains power under Rule 20 to modify the Schedules by gazette notification; the Schedules have not been updated since 2000, leaving several newer industrial chemicals outside MSIHC's threshold-quantity test.

Who qualifies as an MAH installation

Rule 2(ja) defines "Major Accident Hazards (MAH) Installations" as isolated storage and industrial activity at a site handling hazardous chemicals equal to or in excess of the threshold quantities in Column 3 of Schedules 2 and 3. The analysis turns on three inputs: the chemical's presence on a named list, the aggregate quantity at the site (including adjacent sites under the same occupier within 500 metres and connected pipelines), and the activity type.

Schedule 2 applies to isolated storage — storage not associated with an installation listed in Schedule 4. Representative Schedule 2 thresholds include:

• Chlorine: 10 tonnes (lower tier) / 25 tonnes (higher tier with Rules 10-12)
• Ammonia: 60 tonnes / 600 tonnes
• Liquid oxygen: 200 tonnes / 2,000 tonnes
• Sodium chlorate: 25 tonnes / 250 tonnes
• Acrylonitrile: 350 tonnes / 5,000 tonnes
• Flammable gases (Schedule 1 paragraph b(i)): 50 tonnes / 300 tonnes
• Extremely flammable liquids (Schedule 1 paragraph b(ii)): 5,000 tonnes / 50,000 tonnes
• Methyl isocyanate: 150 kg at both tiers
• Carbonyl chloride (phosgene): 750 kg
• Hydrogen sulphide, hydrogen fluoride, hydrogen cyanide, ethylene oxide, propylene oxide: 5 tonnes each

Schedule 3 applies to industrial activities and lists around 180 named chemicals in Part I plus hazard-class thresholds in Part II. Representative Schedule 3 Part I thresholds: aldicarb 100 kg, benzidine 1 kg, carbofuran 100 kg, phosgene 750 kg, parathion 100 kg, nickel tetracarbonyl 10 kg, beryllium powder 10 kg, arsenic trioxide 100 kg. Group-2 toxic substances (Rules 10-12 trigger) include acetone cyanohydrin at 200 tonnes and acrolein at 20 tonnes.

The 500-metre aggregation rule in Schedule 2(a) and Schedule 3(a) is load-bearing: an occupier running two adjacent warehouses each just below threshold cannot escape MAH classification if the aggregate across the boundary (or via a connected pipeline, or in vehicles parked at the site) meets the threshold. Auditing the 500-metre envelope around every storage point is the first diligence step.

Substantive obligations of an MAH occupier

The MSIHC regime escalates through the Rules in a defined sequence:

1. Rule 4 — General responsibility. Every occupier with control of an industrial activity covered by Schedule 1 Part I/II or Schedule 2 must produce documentary evidence of major-accident-hazard identification, steps to prevent major accidents and limit consequences, and arrangements to provide workers with information, training, and equipment (including antidotes). This is a continuing obligation, not a one-time filing.

2. Rule 5 — 48-hour major-accident notification. Where a major accident occurs on a site or in a pipeline, the occupier must within 48 hours notify the concerned authority identified in Schedule 5, in the format prescribed by Schedule 6. The authority then has 90 days to complete its analysis and forward information to the Ministry of Environment, Forests and Climate Change. The occupier must also notify steps taken to avoid repetition. "Major accident" is defined in Rule 2(j) as any incident involving loss of life, ten or more injuries inside and/or one or more injuries outside, release of toxic chemicals, explosion, fire, or spillage resulting in on-site or off-site emergency.

3. Rule 7 — Site notification and approval. Where Schedule 2/3 thresholds are met, the occupier cannot undertake the industrial activity unless they have been granted approval after submitting a Schedule 7 notification at least 90 days before commencement. The authority must approve within 60 days of receipt. Any subsequent introduction of a new hazardous chemical above threshold is deemed a "different activity" requiring fresh notification.

4. Rules 7-9 — Updating and transitional filings. Rule 8 requires forthwith notice of any change that affects Schedule 7 particulars, including increase or decrease in the maximum threshold quantity. Rule 9 gave existing occupiers a three-month window from commencement of the Rules to file their initial notification.

5. Rule 10 — Safety report and independent safety audit. For activities meeting the Schedule 3 Column 4 / Schedule 2 Column 4 higher-tier thresholds (Rules 10-12), the occupier must prepare a Schedule 8 safety report and submit it at least 90 days before commencement. Post-1994 amendment, occupiers must also carry out an independent safety audit with an expert not associated with the activity, forward the auditor's report within 30 days, and update the audit annually. The concerned authority may issue an improvement notice under Rule 19 within 45 days.

6. Rule 13 — On-site emergency plan. The occupier must prepare and keep updated an on-site emergency plan containing the particulars in Schedule 11, detailing how major accidents will be dealt with on site. The plan must name the person responsible for site safety and those authorised to act in an emergency. For a new activity, the plan must exist before commencement; for existing activities, within 90 days of the Rules' commencement. Rule 13(4) mandates a mock drill every six months, with a detailed report immediately available to the concerned authority.

7. Rule 14 — Off-site emergency plan. The concerned authority prepares and maintains the off-site emergency plan using Schedule 12 particulars, drawing on information the occupier must supply. The authority is required to conduct an off-site rehearsal at least once per calendar year.

8. Rule 15 — Public information. The occupier must inform persons outside the site (directly or through the District Emergency Authority) who are likely to be affected, about the nature of the major accident hazard and the "Do's and Don'ts" to be adopted in the event of a major accident. Compliance is required before commencement for new activities; within 90 days of the Rules' commencement for existing activities.

9. Rule 17 — Safety data sheets and labelling. Every hazardous chemical subject to Rule 17 must have a Safety Data Sheet in the Schedule 9 format, accessible on request. Every container must be labelled with contents, manufacturer/importer name and address, and physical/chemical/toxicological data per Schedule 1 Part I criteria.

Interaction with the Public Liability Insurance Act 1991

The Public Liability Insurance Act, 1991 ('PLI Act') imposes a parallel no-fault liability regime on every owner handling a hazardous substance in quantity above the prescribed threshold. Section 4 PLI Act requires every such owner to take out insurance policies under which they are insured against liability to give relief under Section 3 to any person affected by an accident involving the hazardous substance. Policies must be at least equal to the paid-up capital or ₹50 lakh (whichever is less) and not more than ₹50 crore, with additional contribution to the Environment Relief Fund under Section 7A.

MSIHC MAH classification and PLI Act applicability are frequently co-extensive but not identical. The PLI Act schedule draws on the Environment (Protection) Rules 1989 threshold list, which overlaps with — but is not identical to — the MSIHC Schedule 2 and 3 tables. Diligent practice is to run both thresholds simultaneously at site onboarding. An MAH occupier without a subsisting PLI policy is in contravention of Section 4 PLI Act, attracting imprisonment up to six years and fine under Section 14, regardless of whether any accident has occurred.

Interaction with Factories Act Section 41B and EPPR 1996

Factories Act 1948 Section 41B regulates "hazardous processes" — a separate list in the First Schedule to the Act notified by central or state notification. The two regimes are partially overlapping:

• Section 41B Factories Act applies to factories carrying on notified hazardous processes regardless of chemical quantity. Occupier duties include disclosure of process dangers, medical examinations, hazard-specific worker training, an on-site emergency plan, and public information.
• MSIHC Rule 2(ja) applies to any site (factory or not) crossing the Schedule 2 or Schedule 3 threshold quantity.
• EPPR 1996 (Chemical Accidents (Emergency Planning, Preparedness and Response) Rules 1996) overlays a Central, State, District and Local Crisis Group architecture on top of MSIHC Rule 14 off-site planning.

A chlorine bulk plant in a Schedule I hazardous-process factory is regulated under Section 41B, MSIHC (Schedule 2 chlorine @ 10t trigger), EPPR (district crisis group), PLI Act, Hazardous Waste Rules 2016 (for waste streams), and the Factories Act state rules on safety (Gujarat Rule 68B, Maharashtra Rule 73J, etc.). Each track has its own notification, audit, and renewal cadence.

Common compliance gaps

Five recurring failures surface in DGFASLI inspection reports and post-accident regulatory findings:

1. Aggregation under the 500-metre rule — occupiers test each storage tank individually against threshold and miss that the aggregate across adjacent tanks, pipelines, and parked transport vehicles meets the threshold.
2. Stale Schedule 7 notifications — initial notification filed in the 1990s; subsequent plant modifications (addition of new chemicals, capacity expansion) never re-notified despite Rule 8's "forthwith" requirement. Every chemical added above threshold is a "different activity" under Rule 7.
3. Absent or paper mock drills under Rule 13(4) — the six-monthly drill requirement is often satisfied by a tabletop exercise rather than an operational drill, and reports are not submitted to the concerned authority.
4. Independent audit staffed by the occupier's own safety consultant — Rule 10(4) requires the auditor to be "not associated with such industrial activities"; using an in-house safety officer or a long-retained consultant does not satisfy independence.
5. Non-existent or lapsed PLI policy — particularly common where the MAH site is a small occupier that renewed general public-liability cover but not the Environment Relief Fund-linked PLI policy.

State variations

MSIHC is Central delegated legislation under the EP Act and applies uniformly across India, but the concerned authority in Schedule 5, state-specific Factories Rules that overlay MSIHC in a factory setting, and the list of Notified Major Accident Hazard Installations each state has published, vary materially.

The state MAH registers are not published uniformly — Gujarat DISH publishes an annual notified-MAH list; Maharashtra discloses on request; Tamil Nadu and Karnataka maintain lists via their respective state crisis groups under EPPR; Delhi's list is maintained by the CIF and released in the Environment Department's annual report. Multi-state occupiers running MAH sites in two or more states maintain parallel filing calendars keyed to each state's portal.

Enforcement and penalties

MSIHC has no standalone penalty clause. Contraventions are prosecuted under Sections 15-17 of the Environment (Protection) Act, 1986:

• Section 15(1): imprisonment up to five years, or fine up to ₹1 lakh, or both. Continuing contravention: additional fine up to ₹5,000 for every day the default continues.
• Section 15(2): if contravention continues beyond one year post-conviction, imprisonment extends to seven years.
• Section 16: corporate liability — every person in charge and responsible for the conduct of the business at the time of the offence is deemed guilty, subject to the due-diligence defence.
• Section 17: offences by government departments — the head of the department is deemed guilty unless they prove lack of knowledge or due diligence.

Prosecution is instituted by the concerned authority or by a person with 60-day prior notice to the Central Government under Section 19 EP Act. In practice, the state DISH and State Pollution Control Boards are the most active prosecutors; central-sphere installations also face action by the Ministry of Environment, Forests and Climate Change.

Beyond criminal prosecution, an improvement notice under Rule 19 MSIHC can require specified remedial measures; non-compliance with the notice itself attracts EP Act penalty. The 1984 Bhopal Gas Disaster (the direct driver of MSIHC's notification) remains the frame of reference for judicial treatment of MAH failure — the Union Carbide Corporation v. Union of India line of cases and M.C. Mehta v. Union of India (Oleum Gas Leak) absolute-liability doctrine continue to define civil liability exposure for MAH operators.

OSH Code transition note

MSIHC Rules 1989 are notified under the Environment (Protection) Act 1986, not under the Factories Act 1948 or any labour statute. The Occupational Safety, Health and Working Conditions Code 2020 ('OSH Code') replaces 13 central labour statutes but does not absorb MSIHC. Chemical-accident regulation remains with the MoEFCC track (EP Act + MSIHC + EPPR + PLI Act). The OSH Code's Chapter III and Chapter IV (when fully commenced) will continue to operate alongside MSIHC for factory-setting duties on hazardous processes, but the MAH-classification trigger and accident-notification regime are not OSH Code territory. Practitioners advising MAH occupiers must treat the OSH Code and MSIHC as parallel tracks.

Occupier / founder checklist

• Map every hazardous chemical on site against Schedules 1, 2, and 3 — include pipelines, parked vehicles, and adjacent sites within 500 metres under the same occupier.
• Confirm whether the aggregate at any point hits the Schedule 2 or Schedule 3 threshold; document the calculation for inspection.
• If MAH: file or refresh the Schedule 7 site notification with the concerned authority; ensure the last filing reflects current chemicals and quantities.
• Run a Rule 13(4) on-site emergency mock drill every six months; submit the report to the concerned authority within seven days.
• Confirm an unbroken Public Liability Insurance policy under Section 4 PLI Act 1991, with Environment Relief Fund contribution paid to date.
• Keep the Rule 10 independent safety audit annual; verify auditor independence — not the occupier's retained safety consultant.

Sources

1. Manufacture, Storage and Import of Hazardous Chemical Rules, 1989 (S.O. 966(E), 27 November 1989; as amended up to S.O. 57(E), 19 January 2000). https://indiacode.nic.in/
2. Environment (Protection) Act, 1986. https://indiacode.nic.in/handle/123456789/1884
3. Public Liability Insurance Act, 1991. https://indiacode.nic.in/handle/123456789/1926
4. Ministry of Environment, Forests and Climate Change — Hazardous Substances Rules portal. https://moef.gov.in/en/division/environment-divisions/hazardous-substances-management/hazardous-substances-rules/
5. Central Pollution Control Board — Hazardous Substances Management. https://cpcb.nic.in/hazardous-waste-management/
6. Directorate General Factory Advice Service and Labour Institutes (DGFASLI). https://dgfasli.gov.in/
7. Chemical Accidents (Emergency Planning, Preparedness and Response) Rules, 1996 (EPPR). https://moef.gov.in/