What Is Isolation Management? 

Safe work requires careful planning and meticulous preparation. Before starting any task, it’s crucial to disconnect the equipment from sources of energy or toxic substances to avoid unexpected releases causing injury to people or damage to equipment. This involves identifying all potential energy sources and other safety hazards beforehand.

Isolations are often used to protect workers and equipment during work. . First, we need to clarify exactly what is “isolation management”. According to the Australian authority, isolation management, also known as isolation procedure, is “the process taken to isolate all forms of potentially hazardous energy from each other to ensure that an accidental release of hazardous energy does not occur and risk the safety of workers and the work environment”. 

These isolations could include turning off the electrical supply, depressurising the equipment, eliminating hot or cold sources, and securing equipment from movement such as rolling or falling. Furthermore, we must properly shut off, disconnect, and purge process lines containing hazardous fluids or gasses.

Identifying Isolations

On a typical plant, there are several hazards with multiple dependencies and interactions.

In most complex situations, we typically develop isolation procedures ahead of time. These procedures aim to ensure that specific areas of the plant or equipment are safe to work on.

A team of experts will carefully analyse isolation procedures before approving them for use in production. Any changes to the plant, equipment, process conditions, or procedures will likely add more risk and necessitate updating the isolation procedure accordingly. A strict change control procedure is necessary to ensure this takes place reliably.

Not all jobs will require an isolation procedure. The specific isolation required will depend on the level of risk:

• For a low-pressure water system, like a hot water tank, simply shutting off and locking the valves to stop water flow might suffice, along with turning off any power source.
• However, for high-pressure explosive gas systems, a more thorough isolation process called “positive isolation” may be needed. This involves closing and opening valves in a sequence, purging the line to release pressure, physically breaking the line, and adding blank flanges. Then, any remaining gas must be safely removed from the equipment, which requires time, additional personnel, and resources, increasing complexity and risk.

To avoid overcomplicating the isolation procedure and adding unnecessary risk, it’s crucial to conduct a thorough initial risk assessment. The precautions taken should always match the actual level of safety risk.

Relationship Between Permit To Work And Isolation Procedures

The permit to work controls all work on the plant to ensure that it takes place as safely as possible. As part of the permit to work procedure, all safety regulations and precautions need to be identified and implemented. This is essential for safe conditions in high risk environments. Specific hazards are identified, and the relevant isolation procedure is implemented where necessary.

Where there is no predetermined isolation procedure, the permit coordinator, issuer, and isolation officers are the ‘responsible persons’ for a thorough risk assessment and identifying all the necessary individual isolations in consultation with the process operators and other disciplines as necessary.

It is important that isolation management is a disciplined and controlled process and that adequate time and care are taken to ensure that the equipment is made safe. Therefore, isolating equipment is often controlled by a separate special permit to work. This permit to work system ensures that the proper precautions are taken, even when isolating equipment ahead of the main job.

It is also important to verify every isolation before work commences. Verification can involve physical inspection, pressure testing, testing for electrical voltages or currents, gas tests, and so on.  A mobile device can also be used to electronically verify that  the correct isolation point has been locked out using bar codes or near field RFID tags for identification.

Isolations Themselves Introduce New Risks

As with any complex procedure, there are a number of things that can go wrong and which could introduce additional risk. 

For example:

• The incorrect isolation procedure might be applied, exposing employees to a dangerous situation.
• Any specific isolation point might be wrongly identified through incorrect labeling or human error.
• The isolation procedure itself might be very complex, increasing the chance of mistakes, especially if implemented under the time pressure typical in production environments.
• The verification and testing of the isolation points might be flawed.
• A significant source of energy might be overlooked (for example a vessel might still be under pressure even after it is isolated). 

Therefore, every possible measure should be taken to cross-check that the isolation procedure is robust and of the highest possible integrity and that all possible sources of energy are identified. Once people start working, it could be too late.  

Testing Of Equipment Before Handover

At the end of the job, it is sometimes necessary to remove isolations in order to briefly test the equipment before returning the plant to normal operation. This could involve temporarily energising a motor, or other pieces of equipment, opening a valve or removing a slip plate, or any combination thereof.

It is critical that during the testing cycle people continue to be protected from all energy sources. The permit to work procedure should allow for this testing process and ensure that any removal of isolations during, or at the end of a job is properly controlled. 

Lock-Out And Tag-Out Of Isolation Points

Isolation points are usually “locked out” using a physical lock and key system and “tagged” with a printed label containing a summary of the relevant permit information and the job being done. A physical lock will prevent a valve from being opened or switchgear from being changed, for example. This “lock out tag out” is commonly abbreviated as “LOTO”.

Depending on the procedure, each employee or discipline (e.g. electrical or mechanical) that is working on the equipment might have to install their own personal lock. Keys originating from the use of multiple locks can be controlled using a “key safe”, lockbox or similar device.

These lockout systems, provided they are kept simple, can be very effective in ensuring that every person involved remains protected throughout the job. Implementing multiple locks per isolation point also has the advantage of ensuring that every employee concerned must first remove their own lock before the equipment can be re-energised. 

A badly designed lock-out system is characterized by missing keys and a large bolt cutter. If this is the case, then urgent attention is likely required in order to improve the isolation procedure.

Electronic Systems For Managing Isolations 

Management of isolations and the lock-out/tag-out system is an integral part of operational safety. Electronic systems, when properly implemented can greatly help to ensure the integrity of the isolations themselves as well as streamline the process.

Electronic isolation systems can allow for additional verification, for example by scanning bar codes or RFID tags in the field, collecting evidence of each isolation using a mobile device. They can also help manage the complex relationships between physical lock-out and personal locks/keys held by employees working in the plant.

How Intellipermit’s Computer-Based Permit To Work System Can Help?

IntelliPERMIT is designed to help manage the permit-to-work process for hazardous jobs on the plant. IntelliPERMIT includes a comprehensive and integrated system for managing isolations and lock-out/tag-out (LOTO). The system is highly flexible allowing your unique plant-specific workflow to be easily accommodated, while also leveraging your existing investment in safe design and procedures. Should you have a requirement to design complex isolation schemes, IntelliPERMIT includes Isobuilder as an optional integrated module from one of our partners. Isobuilder is interactive isolation design software that allows you to increase the accuracy and efficiency of Isolation design during the PTW process.For more information on how IntelliPERMIT or Isobuilder can help you better manage your plant isolations, talk to the IntelliPERMIT industry experts today.