Process and Machinery Safety

Many installations feature safety instrumented systems (SIS) providing a level of risk reduction and claim to be SIL compliant as per BS EN / IEC 61511. These systems have been designed to bring the process to safe conditions in the event of mal-operation. This safe operation is through the design and implementation of safety instrumented function (SIF) loops and other means of inherently failsafe design.

Many safety instrumented functions are operating in low demand mode, where the final elements such as valves are effectively dormant until needed to act. The only way to ensure that the SIF loop will operate correctly in the event of a trip is via periodic proof testing; a sometimes-overlooked aspect of the safety lifecycle. Without maintaining a proof test and inspection regime an installed SIS cannot be claimed to maintain SIL compliance.

Proof testing differs to normal testing, as a SIF proof test must be designed to reveal otherwise unrevealed faults that prevent the SIS from operating in accordance with the safety requirements specification. The goal is to exercise every active device in the SIF loop. This may be a subset or repeat of many of the steps that should have occurred during the original validation testing.

Inspec Solutions have TÜV certified Functional Safety engineers who understand the importance of regular SIF proof testing in order to maintain the original design integrity levels, and as such we offer a comprehensive testing service to ensure regulatory compliance.

Starting with all available documentation, we review the “As-built” (or As-Validated) documents to baseline the operation. This includes numerous different documents, but typically we start with:

  • Piping & Instrumentation Diagrams
  • Cause and Effects Diagrams
  • Wiring Schematics
  • General Arrangements
  • Safety Requirements Specifications
  • Proof Test Procedures

Where conflicts occur between documents (usually when they have not been well controlled through the systems lifetime, especially in legacy systems), we ensure to understand and document the discrepancies before commencing testing.

After establishing the documentation status, we carry out a physical SIS inspection, in order to anticipate in advance of failures:

  • Inspect for obvious damage or signs of corrosion/degradation
  • Check equipment tags / SIF identification
  • Check software and/or firmware revisions match document records
  • Check for wiring, cable or termination issues
  • Check for poorly supported pipework/cabling
  • Cabinet security from unauthorised access
  • Signs of moisture/water ingress
  • Leaks from piping or gaskets

The above list is not exhaustive, and the original equipment supplier installation/operation/maintenance manuals will be used to provide further information to understand operation.

At the end of the inspection phase, the “As-Is” status of the equipment is recorded before any test or rectification of problems takes place. This ensures that causes of problems are captured prior to problems being fixed.

Following the initial inspection, SIF proof testing is commenced. Testing is preferably completed offline, when the equipment is not in-service protecting against a real hazard, although online testing can be carried out in a closely controlled and monitored manner.

The result of the testing is fully documented so that the records can be used for regulatory compliance, future improvement where appropriate and elimination of potentially dangerous failures.

Typically, the testing report contains;

  • Document name, unique number, issue date, author and revision information
  • A list of documentation that was reviewed before the tests were undertaken
  • Information on the document audience, detailing who is intended to use the procedure and perform each task
  • Any special tools, equipment, or access requirements for the test
  • Instruction & fields to record tags, SIF loop identifier, software and firmware, where applicable
  • Specific instructions to record the current condition of each active SIF device
  • Detail of the hazard and consequences of failure, with mitigating measures for on-line tests
  • Detailed step-by-step task instructions for the test sequence
  • Pass / Fail criteria per step, with comments
  • Space to record the post-test condition of each device
  • Space to record the tester name, signature and date(s) of the test 

Inspec Solutions SIF Proof Testing service is designed to ensure that your systems maintain compliance and operations whilst removing the distractions from your maintenance personnel.

From the smallest standalone machine to large scale heavy industrial plant, Inspec Solutions understand the need for our Customers operations to be safe.

Our safety consultants can advise to ensure relevant directives are met, helping make our Customers operations safe. From the outset we advise on compliance with the latest publications of IEC 61511 / BS EN 61511 and IEC 61508 / BS EN 61508 where applicable.

Inspec Solutions can support you at all stages of the SIS safety life-cycle. We provide consultancy services from the initial stages of HAZOP and LOPA, through to production of Safety Requirements Specifications (SRS), design of the instrumented systems, installation, commissioning and ongoing life-cycle support, with verification throughout.

Our flexible approach allows our Customers to take advantage of our functional safety expertise at any point in the safety life-cycle, from inception to ongoing verifications and proof testing. We can provide independent consultancy working alongside our Customers incumbent suppliers to ensure all elements are covered.

We understand that to ensure SIL compliance supporting documentation must be provided along with rigorous design and implementation. Our functional safety engineers ensure that all the necessary components and procedures are in place to ensure HSE compliance. We regularly perform functional safety assessments, procedural reports and verifications to ensure our Customers exceed HSE expectations during inspections, whether those systems have been supplied by Inspec Solutions or others.

Working as a team our consultancy services ensure that our Customers understand the application and implementation of process safety in their operations and we emphasise knowledge transfer and collaboration throughout the whole process. This collaborative approach to process safety provides our Customers with the knowledge that they are compliant with regulations and have systems and procedures in place to ensure continued safe operations.

From the smallest standalone machine, to large scale heavy industrial plant, Inspec Solutions understand the need for our Customers staff to be safe at work.
All employers must provide a safe working environment for their employees and any new equipment must conform to the essential legal requirements of European Community law.

Since 1995 the Machinery Directive 89/392/EEC has been implemented into UK Law by the Supply of Machinery (Safety) Regulations 2008 (Statutory Instrument 2008:1597), and the Use of Work Equipment Directive 2009/104/EC, as the Provision and Use of Work Equipment Regulations 1998 (PUWER) placing duties on people and companies that are enforced by the Health and Safety Executive. Penalties for non-compliant machinery can be severe.
Inspec Solutions TUV certified consultants understand the requirements are able to offer advice to ensure that equipment includes appropriate health and safety measures.

Our safety consultants can advise to ensure the directives are met to help make equipment safe for use, including:

  • The Machinery Directive 2006/42/EU
  • The Low Voltage Directive 2014/35/EU
  • The Pressure Equipment Directive 2014/29/EU
  • The ATEX Directive 2014/34/EU
  • The EMC Directive 2014/30/EU
  • The Restriction of Hazardous Substances Directive 2011/65/EU

Inspec Solutions has gained huge experience of control and safety systems over many years. Our systems are often integrated to plants in the manufacturing industry and process sector. These applications are often inherently hazardous, and Inspec Solution consultants have grown a deep understanding of the hazards and risks they see. 

All control systems we deliver adhere to the latest international safety regulations, directives and standards, but we also offer consultancy services on existing and legacy systems. 

Inspec Solutions experienced and qualified consultants and engineers can:

  • Carry out Site and Machine Safety Surveys
  • Prepare Risk Assessments and Hazard Analysis
  • Produce Machinery Directive Annex 1 Essential Health & Safety Requirements Reports
  • Advise on Technical File Content
  • Recommend Risk Reduction Measures

Our Customers can be confident that we will help them to ensure that their plant or system are safe for operators, materials and plant, and the environment around, providing a safe working environment for employees, protecting our Customers corporate reputation and ensuring compliance with Commercial and Criminal Law.  

“Following a recent HSE audit Wavin have gone above and beyond the remit of the audit, committing to Functional Safety at every level of the business.

Inspec Solutions have supported Wavin every step of the way with HAZOP, LOPA & SIL verification services in an exemplary manner, advising and executing the work in a highly professional and quality way. Their support has been invaluable in our continued drive for the safety of our hazardous processes.”

Chris Earl – Site Operations Manager – Clayware and Balbriggan – Wavin