If your facility deals with hazardous substances in Malaysia, you’ve probably heard of the CIMAH Report and DOSO Report. But are they the same thing? Which one applies to your company? And when do you need to submit them?
In this post, we clarify the difference between the CIMAH Report and the DOSO Report under the Control of Industrial Major Accident Hazards (CIMAH) Regulations 1996.
🧩 First, What is CIMAH?
CIMAH (under OSHA 1994) regulates industrial activities involving hazardous substances. Its goal is to prevent major accidents such as fires, explosions, and toxic releases — and minimize their impact on workers, the public, and the environment.
CIMAH classifies facilities based on the quantity of hazardous substances present:
- Lower Tier: Above lower threshold levels.
- Upper Tier: Above higher threshold levels.
Depending on your classification, you’re required to submit specific safety documentation to the Department of Occupational Safety and Health (DOSH) — and that’s where the CIMAH and DOSO Reports come in.
📘 What is a CIMAH Report?
The CIMAH Report (also called the Safety Report) is a comprehensive technical document required for Upper Tier Establishments.
It includes:
- Hazard identification and risk assessment
- Process safety and control systems
- Preventive measures and mitigation systems
- Emergency response plans
- Impact assessments
- Safety management systems
The CIMAH Report demonstrates that the operator has: ✅ Identified potential major accident hazards
✅ Put appropriate safety measures in place
✅ Prepared for emergencies
✅ Minimized potential off-site impacts
🛑 It is not just a form — it’s a detailed engineering and management report.
📄 What is a DOSO Report?
The DOSO Report (Demonstration of Safe Operations) is a summary report required for Lower Tier Establishments under CIMAH.
It includes:
- A notification to DOSH that the facility falls under the lower tier
- A brief Major Accident Prevention Policy
- A summary of safety measures in place
- Basic information on hazardous substances and processes
The DOSO Report is shorter and less technical than a full CIMAH Report, but it still shows the operator is aware of the hazards and has taken steps to control them.
📊 CIMAH Report vs. DOSO Report — Side-by-Side Comparison
| Feature | CIMAH Report | DOSO Report |
|---|---|---|
| Applies to | Upper Tier Establishments | Lower Tier Establishments |
| Required by | CIMAH Regulation 17 | CIMAH Regulation 10 |
| Submitted to | DOSH Malaysia | DOSH Malaysia |
| Content Depth | Very detailed (Safety Report) | Summary and MAPP |
| Includes Emergency Planning | ✔️ Yes | ❌ Not required |
| Public Information | ✔️ Yes | ❌ Not required |
📌 When Do You Submit Each Report?
- Lower Tier (DOSO Report)
Submit before commencing operation, or upon exceeding the lower threshold of hazardous substances. - Upper Tier (CIMAH Report)
Submit at least 3 months before starting operations, or within 12 months of exceeding the upper threshold — whichever is earlier.
⚠️ Updates are required if there are significant changes in processes or substances used.
💬 Why It’s Important to Know the Difference
Submitting the wrong report or missing a submission altogether can lead to:
- Legal non-compliance
- DOSH enforcement actions
- Delays in project approvals or licenses
- Increased accident risks
Knowing whether you need a CIMAH Report or a DOSO Report helps your organization stay compliant, reduce risks, and build credibility with authorities and the public.
🛠️ Need Help Preparing Your Reports?
At PLC Group, we help industries across Malaysia develop and submit CIMAH and DOSO Reports that meet regulatory requirements. Our experienced consultants handle everything from site assessments to document preparation, training, and regulatory follow-up.
📞 Contact us today for a free consultation or email us at plc@plc-group.com.