Functional Safety

We offer safety solutions for the oil and gas industry and custom applications to meet your specific needs. The objective of Functional Safety is to ensure levels of acceptable risk to prevent physical injury, damage to property or to the environment. We offer consultation services to ensure that performance level of every safety function is met. Services include HAZIDs/HAZOPs for identification of safety functions, Safety Integrity Level assessments, ensuring safety functions perform to design intent and conducting safety audits. Our safety solution lifecycle helps to ensure projects are executed thoroughly from hazard identification, evaluating safeguarding options, validation and through to maintenance and change control.

The IEC 61508 and IEC 61511 international safety standards for the process sector are global benchmarks for "good practice" in functional safety. Our offering is to help you meet regulatory and compliance requirements through functional safety management and IEC 61508/61511 benchmarking. Demonstrating evidence of compliance to the functional safety management requirements of IEC 61508/61511 is increasingly seen as a pre-requisite to demonstrate good practice safety management.

Onacom has experience and expertise in functional safety management, safety-related system design and engineering, audits and assessments. Our TUV FSEng functional safety consultants and competent auditors can deliver a range of independent audit and assessment services.

Our offerings include:

Functional Safety Management

It has become necessary to demonstrate that management of the safety system design activities and implementation is appropriate and competence requirements met. Onacom is able to setup Functional Safety Management Systems for compliance to the recognised IEC61508 and IEC61511 and safety standards. We can assist you with achieving functional safety through our specifying, implementing and maintenance processes.

SPECIFYING : Target Safety integrity level (SIL)
IMPLEMENTING : Design, testing & validation to SIL target
MAINTENANCE: Maintenance in accordance with the SIL Target

Onacom can help assure all three areas are effectively executed. To facilitate the Functional Safety, Onacom has developed a suite of procedures. We can provide guidance during every stage of the Functional Safety lifecycle for small safety modifications to assessing complete installations.

Hazard and Operability Studies

Onacom can help facilitate Hazard and Operability (HAZOP) assessments. We can provide experienced chairpersons for projects from conceptual engineering to detailed design and can include analytical services and operations support.

SIL Assessments - Risk Graphs, LOPA

Onacom can help facilitate multidiscipline group SIL assessments. We are fully versed with the Risk Graph (RG) and the Layers of Protection Analysis (LOPA) methods of SIL targeting. Establishing the appropriate Safety Integrity Level (SIL) for each function involves critically evaluating combinations of failure of equipment and its controls which lead to Hazards.

Corporate data information on acceptable risk criteria must be provided by the client.

SIL Verification

Onacom's team of reliability engineers can assess the SIL capability of specified Safety Instrumented Functions (SIFs). Our engineers are fully versed with the Fault Tree Analysis, Reliability Block Diagrams (RBDs) and Failure Modes Effects and Criticality Analysis (FMECA) methods.

The SIL verification assessments can be conducted using the client's failure rate data or Onacom's own database. Our SIL verification process includes calculation of Safe Failure Fraction (SFF) and assessment against IEC 61508 / IEC 61511 architectural constraints in terms of hardware fault tolerance.


Onacom offers on-site or off-site Functional Safety training and workshops. The training and content can be tailored to specific requirements of the clients and to suit operations or management personnel.

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