Preparing for safety case
Information and guides to help you prepare and organise information for your safety case.
At a glance
How to prepare
Because each MHI has variations in design and operation philosophy, you can determine how best to organise information in your safety case.
The Major Hazards Department (MHD) will inform each MHI on the safety case submission date upon receipt of the MHI assessment form.
Guides
You can refer to the following documents to understand the content expected for safety case:
- Safety case technical guide
Describes how a safety case should be prepared to meet the requirements of the WSH (MHI) Regulations. - Safety case assessment guide
Describes the framework and approach used in the assessment of safety cases. - Safety case Electrical, Control & Instrumentation (EC&I) aspects
- Guidelines on safety instrumented systems in MHI
Provides guidance on safety instrumented systems and instrumented protective systems in EC&I aspects - ALARP demonstration guidelines: Single scenario risk tolerability target and adequacy of barriers
- FAQ for ALARP demonstration guidelines
Provides guidance on achieving sound ALARP demonstrations in Safety Cases - Guidelines on managing human factors in Major Hazards Installations
Provide guidance on identifying human failures and management of human performance to improve human reliability -
Key Findings from Safety Case Assessment Intervention Plans
Provides guidance on demonstrating the effectiveness and reliability of protective measures that have been put in place by MHIs.
Key activities
These are the key activities for the safety case:
| Activity | Outcome |
| Attend pre-receipt meeting | Alignment of your approach to develop safety case. |
| Submit safety case | Receive MHD’s conclusions of the safety case assessment. |
| Act on safety case conclusions |
|
| Review safety case |
|
Attend pre-receipt meetingShow
When: At least 6 months before you submit the safety case.
The purpose of the pre-receipt meeting is to seek alignment on the key principles and approaches used by your MHI in the development of your safety case.
You need to have the following items prepared for discussion at the pre-receipt meeting:
- Descriptive information of the MHI.
- Predictive aspects – Methodology and the selection of:
- Major Accident Scenarios (MAS)
- Representative set of MAS
- Safety Critical Events (SCE)
- ALARP methodology and ALARP demonstration of one SCE.
Conclusions of the meeting will be documented in a pre-receipt summary, which will be emailed to you.
Submit safety caseShow
Processing time: About 6 months.
May take longer if there are delays in responding to MHD’s clarifications or unresolved safety case issues.
- To submit safety case, email 1 softcopy of your safety case to:
- Email of your designated point of contact in MHD; or
- contact_mhd@mom.gov.sg
- MHD will assess your safety case and seek clarifications, if required. On-site verification will be conducted to verify the implementation of the measures described in the safety case.
- When assessment is completed, you will receive:
- Conclusions of the safety case assessment.
- Intervention Plan capture all planned interventions over the next 5 years based on the conclusion of safety case assessment.
Act on safety case conclusionsShow
MHIs must:
- Follow-up on all the action items in the Intervention Plan.
- Ensure that the control measures described in the safety case are properly implemented, and that relevant documents are available for verification.
MHD will inspect your MHI to check on implementation progress according to the Intervention Plan.
We will share detailed yearly intervention plans (IP1, IP2, IP3, IP4) with your MHI. They will be aligned to the Intervention Plan, and will include:
- All planned interventions
- Issues of non-compliance
- Findings from safety case assessment
- Inspections
- Ongoing investigation work
Review safety caseShow
To ensure that your safety case remains updated and relevant to your operations, you need to review, and if necessary, revise your safety case:
- Every 5 years.
- When there is new knowledge or modifications at your workplace.
The review should include:
- Details on the changes that have occurred.
- Assessment of the significance of the changes on the identification, prevention, control and mitigation of major accidents.
- Cumulative effects of minor changes that have taken place.
For review every 5 years
- Update your safety case by consolidating all outstanding and actioned items into the safety case.
- Inform MHD of revision details using the safety case revision form.
Before making significant changes
E.g. plant modifications or changing the quantities of dangerous substances.
- Consult MHD to determine if you need to conduct a Quantitative Risk Assessment (QRA).
- Notify MHD upon confirmation of your modifications and planned commissioning date.
- Review and revise safety case.
- Submit the revised safety case to MHD for assessment.
For other changes
- Revise safety case.
- Inform MHD of revision details using the safety case revision form.