Isolation and maintenance of machinery and plant

A waste and recycling company in London clearly wasn’t up to speed with the regulations and as such, they paid a heavy price when one of their employees was injured while carrying out maintenance.  

In September 2020, the employee sustained severe injuries after he became trapped between a conveyor and a metal bridge which formed part of a waste sorting machine.  

He had entered the machine to carry out repairs to the mesh of the hopper but the machine hadn’t been isolated from all power sources and it was inadvertently switched on.  

Following the incident, the HSE investigated and found that the business had “failed to provide a suitable means to isolate the machinery from all sources of energy”. 

It was revealed that the isolator switch was broken and therefore couldn’t be used.  

The investigation also showed that the company didn’t have any formal arrangements for machinery maintenance.     

When the case came to court in October 2023, the company pleaded guilty to breaching Section 2(1) of the Health and Safety at Work Act 1974, which says:  

“It shall be the duty of every employer to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all…employees”  

They were fined £260,000 and ordered to pay £4,358 in costs.  

An HSE inspector said  

“The fine imposed should underline…that the courts, and HSE, take a failure to ensure that maintenance work is completed safely extremely seriously.” 

“We will not hesitate to take action against companies which do not do all that they should to keep people safe.” 

Given the severe consequences of not ensuring plant and machinery safety, what steps can be taken to avoid accidents and incidents like this?  

What the law says 

Under the Provision and Use of Work Equipment Regulations 1998, also known as PUWER, employers must ensure equipment provided for work is safe and suitable for its intended use.  

Reducing risks   

To reduce the risks from plant and machinery, the employer should follow these steps: 

  • Carry out a risk assessment  
  • Set up and use safe systems of work  
  • Ensure a health and safety policy is drafted, implemented and regularly reviewed  
  • Equip employees with personal protective equipment, but only what the risk assessment says is needed. (Remember that PPE is the lowest rung of the safety hierarchy, and all other steps must be observed first) 
  • Put up appropriate signs and warning systems  
  • Ensure employees are properly trained on the equipment that they will be using 
  • If employees need to report issues they have encountered, there need to be clear procedures in place to enable them to do so 
  • Ensure emergency stop switches are placed where they are most likely to be needed in an emergency situation 
  • Ensure machine guards are in place where this is required for safe operation of the machinery 

What does PUWER say about isolation from sources of energy?  

Isolation from sources of energy 

19.— (1) Every employer shall ensure that where appropriate work equipment is provided with suitable means to isolate it from all its sources of energy. 

(2) Without prejudice to the generality of paragraph (1), the means mentioned in that paragraph shall not be suitable unless they are clearly identifiable and readily accessible. 

(3) Every employer shall take appropriate measures to ensure that re-connection of any energy source to work equipment does not expose any person using the work equipment to any risk to his health or safety. 

The most common sources of energy are power, heat and pressure but there are others – it depends on the particular equipment. A risk assessment will therefore need to cover them all.  

It’s also important to ensure that the means of isolation are constructed to recognised standards where possible and that they are robust enough to withstand the same operating conditions as the equipment.  

Attention also needs to be paid to the restoration of energy to the equipment and that this is done in a safe manner.  

Employers must ensure that people are not put at risk when the energy source is reconnected from unexpected movement or other hazards.  

Guards and other protection devices must therefore be re-fitted and function properly before operation begins.  


As noted above, the HSE investigation found that the company had no formal maintenance arrangements for the machinery. 

A maintenance schedule involving a competent person is crucial to ensuring the safety of all employees using the machinery.  

Proper maintenance procedures will:  

  • reduce breakdowns 
  • cut down lost time or production 
  • reduce the risk of injury and accidents by sudden failure of plant/machinery 
  • reduce the risks of civil claims from accidents/injuries 
  • make plant/machinery more efficient, which can also lead to lower energy costs   
  • extend the working life of the plant/machinery. 

Before beginning any maintenance procedure on machinery or plant, it’s important to make sure that: 

  • the plant/machinery is in a safe area free of other hazards and has been allowed to cool down 
  • the power supply is isolated (see above) 
  • other energy sources, such as compressed air and petrol, are discharged; 
  • any part held by hydraulics is lowered or chocked 
  • others are locked out of the equipment/system 
  • the lighting is sufficient to carry out maintenance 
  • if necessary, working at height protocols are in place 
  • emergency procedures are in place 

Making sure that machinery and plant are safe for workers to use is a complex process that requires the services of a competent person. If no such person is available in the workforce, it is a very good idea to consult an external expert who can provide guidance and direction on how to comply with the law and keep the workforce safe.