SIL: Safety Integrity Level
SIL (Safety Integrity Level) certification is a globally recognised standard for assessing the functional safety of systems. Introduced by IEC 61508, this certification has become an essential reference for companies operating in critical sectors such as the chemical industry, energy, industrial automation and transport.
SIL: historical overview
Functional safety began to receive increasing attention in the 1980s, following a number of serious industrial accidents that highlighted the need for international standards for risk management. IEC 61508, introduced in the 1990s, was the first global attempt to provide a comprehensive framework for the design, implementation and management of safe systems. SIL certification was developed as an integral part of this standard, providing a clear metric for assessing the reliability of safety functions.
The evolution of Safety Integrity Level standards has been strongly influenced by the petrochemical and gas industries, where risk management is crucial. Over time, the SIL concept has also been adopted in other industries, from automotive to rail and industrial automation.
SIL: what is it?
The SIL represents a safety integrity level, i.e. a quantitative measure of the risk reduction associated with a specific system or component. SIL levels range from 1 to 4, where:
- SIL 1: represents the minimum level of risk reduction
- SIL 4: represents the highest level of risk reduction, required for critical high reliability systems
Each level is defined by an acceptable probability of failure for the safety function and specific requirements for design, implementation and maintenance.
SIL: how is the level determined and what are the requirements?
The determination of the required level for a system is the result of a detailed risk analysis, which assesses:
- The severity of the consequences in the event of a failure
- The frequency and probability of dangerous events
- The ability to mitigate the risk through safety measures
In addition, to obtain SIL certification, a system must meet a number of technical and management requirements, including:
- Reliable design: Use of certified components and redundancy in critical systems
- Validation and verification: Rigorous testing to ensure that the system meets safety requirements
- Continuous maintenance: Implementation of maintenance plans to preserve the level of security over time
SIL: why is it important?
In ensuring that safety systems are designed and operated to reduce risks to acceptable levels, SIL certification plays an essential role. In the field of gas detection it is possible to certify the product according to EN 61508 and EN 50402, a standard developed specifically for the functional safety of gas detection systems. Sensitron has certified both detectors and control panels with a SIL2 rating for the hardware part and SIL3 for the firmware, according to EN 610508 and EN 50402.
A certified system protects people and the environment, minimising the risk of accidents with potentially catastrophic impacts. It also demonstrates compliance with safety regulations required by law and regulatory bodies, avoiding penalties and costs associated with plant downtime or repairs. This investment in functional safety also enhances the company’s reputation, strengthening the trust of customers, partners and stakeholders. SIL certification is not just a matter of regulatory compliance, but a commitment to a preventive approach to risk management.
Discover our SIL certified products
SMART 3G D2
Suitable for detecting flammable substances, toxic gases, refrigerants and oxygen in classified areas.
Certified ATEX Category 2 for Zone 1, IECEx and SIL2/3
SMART 3G D3
Suitable for detecting in classified areas, Certified ATEX Category 2 for Zone 1, IECEx and SIL2/3, allows non-intrusive field calibration.
MULTISCAN ++S1/++S2
Designed to meet the widest demand from the market, they allow management of up to 264 detectors. ATEX and SIL certified.
