This document discusses functional safety standards for mining operations that are introducing automation. Traditional risk management in mining relies on equipment suppliers incorporating safety controls and operators detecting abnormal conditions. However, automation introduces new hazards as personnel still need to approach automated equipment for maintenance. Functional safety standards provide tools to identify and manage these new hazards through defining safety lifecycles and integrity requirements based on risk. Maintaining functional safety over the operational life requires ongoing evaluation of assumptions, component failures, demands on safety systems, proof testing, and ensuring appropriate documentation and procedures are followed.

1. Functional Safety

2. 2
Determining Validity of Claims and Life Cycle Issues

3. 3
Traditional risk management in mining
•
Supplier of equipment incorporates risk controls in supplied plant;
•
Asset operator develops operating and isolation procedures;
•
Heavy reliance on exclusion and operators detecting abnormal conditions.

4. 4
The introduction of automation
•
Introduces new hazards as personnel must approach automated plant to replenish consumables and maintenance
•
Methods of isolation more complex (full energy isolation sometimes not an option)
•
Mobile plant now has capacity to leave the work area
•
No personnel present to detect abnormal conditions
Source: RoboMine, JM Chui and JA Meech
University of BC, Vancouver

5. 5
Functional safety standards
•
Provide tools/techniques to allow new types of hazards to be identified and managed
•
Defines a lifecycle with appropriate activities to maintain level of functional safety
•
Provides a means of determining integrity requirements based on risk

6. 6
Functional safety during the operational life requires…

Ongoing evaluation of assumptions made during analysis and design

Critical assessment of component failures

Active monitoring of demands on the safety system

Supporting documentation to be maintained

Well defined operation and maintenance procedures, including repair

Formal proof testing

7. 7
Component failures
Component
failure
Is assumed
reliability correct?
Are there
Environment
Factors?
Compromise SIL
Just replacing unit
ineffective
Highlight
design assumption
errors
Component
suitability

8. 8
Demands
Demand on safety function
Is demand rate as
expected?
Was the initiating
event considered in
the analysis?
Risk profile incorrect
Hazard identification
incomplete
Hazard scenario
Not understood

9. 9
Protection layers
Protection
Layers
How often are they
preventing a demand?
How effective are they?
Risk profile incorrect
Hazard identification
incomplete
Hazard scenario
Not understood

10. 10
Proof testing
Proof testing
Incomplete test coverage
Proof testing not done to schedule
Reliability
compromised
PFD compromised
Dormant dangerous undetected faults not identified
Testing not performed

11. 11
Competency
Functional safety and autonomous technologies introduce additional competency requirements
More than just training……….
Those involved in safety lifecycle activities must be competent by virtue of their education, training and experience.
Underpinning knowledge
Behavioral skills
Underpinning Understanding
Technical skills
Competency
Types

12. 12
Audits
•
Evaluate if planned activities are being performed
•
Consider specific activities
•
Evaluate if activity being performed as defined
•
Does not judge if activity correctly defined
•
Ensure planned activities are being performed
•
Procedural controls need to be audited

13. 13
Functional safety assessment
•
Make a judgment on the level of functional safety achieved
•
Can be done after each phase or prior to hazards being present
•
Undertaken periodically whilst hazards are present (e.g. for the life of the plant)
•
Undertaken by competent persons
•
Level of independence required

14. 14
Conclusion
•
As we take the next steps in mining automation there will be more obligations on the end user based on design decisions made by the supplier.
•
End users need to understand what is required to accept and maintain a functional safety system in order to ensure it is not compromised over time, exposing their personnel to unacceptable risk.

15. 15
Thank you!
Lyn Fernie
Business Manager – Consulting
HIMA Australia Pty Ltd.
Mobile: +61 (0) 438 980 495
Email: Ifernie@hima.com.au