How to safely bring mothballed assets back into operation

Paul Wood

The last two years in the industry have been some of the most challenging many of us have encountered in our careers or are likely to ever see again. The pandemic brought about global issues that many had never anticipated. Despite governments having an emergency response plan to deploy in the event of such a situation, the speed and scale at which the pandemic took hold and shut down the global economy and industry were unprecedented.

With the imposition of lockdowns, many companies were unsure how to respond and in a lot of cases, this resulted in mass furlough schemes for staff and the stopping of plants until a clearer path out of the chaos emerged.

From an asset point of view, this meant many were simply switched off thinking it would be a ‘couple of months’ before normality returns… how wrong they were! This has left many companies with residual risks in assets that were not correctly mothballed and ‘put to bed’ safely and that has now sat idle for what could be over 2 years.

Although there is still some uncertainty due to other global issues, a lot of businesses are now coming out of the other side of the pandemic and want to get their assets back up and running.

Careful consideration should be given to how plant is brought back online. To assume that it can simply be turned on and be back up to full operational capacity straight away could be a dangerous and costly assumption.

Even if a detailed mothballing plan was instigated during switch off, bringing it back online should involve the same level of detail if not more.

What to check?

Consideration should be given to the following as a minimum and will depend on the type of machinery and processes involved;

  • Statutory compliance – Safety regulations such as the Provision and Use of Workplace Equipment Regulations (PUWER) require companies to maintain all the equipment in an efficient state by applying robust maintenance. This includes ensuring all statutory inspections are up to date e.g. LOLER, PSSR, LEV, and Fire Systems before use.
  • Mechanical equipment – Whilst mechanical equipment is quite forgiving, not checking things like gearboxes, lubrication systems, hydraulic and pneumatic pressure systems, and fan systems could lead to costly remedial works. Water systems may require flushing, chlorinating, refilling or filter changes. Pipework and valves should be checked for condition and operation. Pumps and couplings should be checked for free rotation before putting them under full start-up loads. Also ensure that any legionella checks are undertaken prior to operation.
  • Electrical systems – If electrical equipment has been left switched off and unheated then there is a risk of moisture damage. Inspection of panels, terminations and reintroduction of some warmth can help minimise start-up issues but sometimes the damage is already done. A general cable inspection should also be performed as vermin damage is not uncommon. Things like local I/O, e-stops and safety interlock functionality should also be considered in pre-start-up checks.

It is important to note that the above is only intended as a guide and that an asset-specific plan should be developed using the people with the correct level of knowledge, competence, and expertise.


Once all safety systems and basic checks have been completed, a controlled start-up can be undertaken, ideally following an original commissioning style approach but it is important to document all checks and tests performed for future reference.

This process should be backed up with a suitable risk assessment detailing the potential risks and controls that will be implemented as it is likely the recommissioning process may not follow normal operational practices.

Where possible, a steady ramping up of speed may also help identify issues and allow early intervention.

Only once all checks have been completed and passed satisfactorily should the asset be returned to full service and even then, may have some initial restrictions.

Changes in resource

In some instances, the aftermath of the pandemic may mean you are operating with different operator configurations, with fewer operators to run or maintain the assets. This change should be carefully considered to ensure that it doesn’t expose you to other risks. What checks or tasks are being missed or carried out less frequently, are other controls or mitigations required?

This change in circumstance also presents an opportunity to undertake a maintenance review which can streamline existing schedules but also identify gaps or opportunities to improve.


It is highly likely that some unforeseen costs will be incurred during this process, but it is also likely that these costs will be much lower and have less impact than if the asset is simply restarted and then issues occur.


The main takeaway thought is that if something has been switched off for a long time, it is advisable to put some thought behind restarting it to prevent risk, avoidable costs and impacts on business operations being incurred.

If you are interested in receiving support or advice for restarting your assets or simply want to discuss the other Asset Management services which Finch can offer, please get in touch with [email protected]

Related insights