Please get in touch if you would like to discuss RC62 or installing solar at your business or organisation.
As more businesses and organisations turn to solar to help reduce energy bills and carbon emissions, fire safety is becoming a growing concern with duty holders, landlords and insurance companies.
Although there is a risk of fire with any electrical installation, we would like to highlight at the outset that there are millions of solar PV installations across the UK and only a fraction of these systems catch fire each year.
Any technology that involves electricity can catch fire, however many have measures in place to prevent fires from occurring.
Therefore companies should ensure their chosen solar supplier is implementing measures and systems to help mitigate the risk of fire and limit the impact in the event of a fire.
This is why, as a leading commercial solar panel company, we fully adhere to all RC62 recommendations.
There are a number of reasons why solar PV systems catch fire, many are covered in the RC62 documentation. These include:
Poor quality of installation – Be sure to use an experienced and reputable company like AR Power when choosing a solar installer.
Pests – Pests such as birds can nest in your solar panels as they emit heat, when nesting they can pull at wires and damage them. This is why solar installation companies use bird guards and deterrent systems.
Poor maintenance – If you don’t look after your investment and have it maintained on a regular basis then the system can degrade, electrical faults can go undetected, and the risk of fire is increased. Solar panel cleaning is also recommended to reduce the risk of fire and to maximise your return on investment.
Equipment – Using equipment from Tier 1 manufacturers can help reduce the risk of fires. These manufacturers will put their equipment through all of the necessary quality assurance tests before it leaves their manufacturing facility.
Changes to system – If you plan to make any changes to the system or have any work carried out, ensuring you have a knowledgeable, experienced and certified engineer who understand the original installation work on your system is paramount. If not, then this may cause overloading of inverters and other issues which can lead to fires.
RC62 is a Joint Code of Practice (JCoP) for fire safety with photovoltaic panel installations, with focus on commercial rooftop mounted systems developed by the RISCAuthority and the Microgeneration Certification Scheme (MCS), with the support of Solar Energy UK.
RISCAuthority membership, managed by the Fire Protection Association (FPA), is made up of UK insurers that support expert working groups developing and promoting best practice for the protection of people, property, business, and the environment from the negative impacts caused by fire and other risks.
The MCS have said “We envisage that this new edition of RC62 will help solar contractors to safeguard against and mitigate fire risk at all stages of an installation. By working alongside the FPA and SEUK to realise these changes, we have been able to ensure that the industry continues to represent its own needs and ultimately provides consumers with the reassurance that safety is paramount when it comes to solar.”
It is guidance on how to help minimise the risk of fire and the impact of a fire when deploying solar PV systems to buildings in the UK.
More and more insurance providers are now asking that RC62 recommendations and preventative measures are put in place when deploying new commercial solar PV projects. They also ask that the systems are maintained on an annual basis to help reduce the risk of fire.
Compliance with fire safety legislation
All solar installations must have a fire risk assessment carried out by a competent person. It is also recommended that you consider time to respond and roof access should there be a fire.
You should speak to your insurance provider about the project and what measures they may require to be put in place to help protect the building and its contents. You should also ascertain who owns the building and the Solar PV system as it may not be the same.
Determine if the existing roofing materials are suitable for the solar PV system and ensure they will not be affected by stray electrical currents.
New PV systems should not compromise the fire rating of the roof. Use fire resistant coverings where installation on a partly combustible roof is unavoidable.
Determine if a DC disconnection switch that is integrated with the current fire system is needed.
Will the inverter arc fault circuit interrupter is acceptable if fitted, and if one is needed, mandatory or not required.
Ascertain whether measures will be put in place to assist firefighters and first responders.
Assess the potential points of ignition within the solar PV system due to some areas of sites being at high risk of combustion. Introducing electrical equipment to some areas where there was none before may pose a risk.
Business continuity
You should take into account that the solar PV system will be operating when no-one is at your workplace. It is recommended that you consider the fire safety implications when designing a system and equipment will be places in an unattended location.
Fire safety management
No hot work should be carried out near solar PV equipment. This includes welding, flame cutting and other activities, unless unavoidable.
When the system is commissioned, a full and thorough handover should be completed by the installer showing the nominated operator of the system the functions and controls. Information on inspecting the system and routine maintenance should also be provided.
Automatic fire detection should be installed where the inverters, isolator and distribution boards are located.
Inverters should not be blocked and allowed adequate ventilation.
PV installations should be serviced and maintained in accordance with the installation company’s recommendations and to BS EN IEC 62446-2(2020).
Hazard consideration
Companies should consider the increased risk of fire when adding solar PV and assessed accordingly, and PV systems should not be installed on non-combustible roofs.
Considerations should be made around the ventilation of a roof and the additional weight applied to the roof from the panels, ballast, rain and snow. Gaps in the system where debris and foliage can build up can also cause a risk of fire.
Design
All solar PV systems should be designed and incorporate solutions to minimise the risk of fire and with all IET PV Code of Practice and MCS requirements met.
The design team designing the solar PV system should be competent and experienced to design a PV system that will mitigate all risks identified in the risk assessment.
If the design cannot be classified as low voltage then a remote switch must be placed at ground level that will isolate the DC strings at the modules. Arc suppression systems should also be implemented into the design.
Electrical devices that switch the modules to extra low voltage when the AC supply is disconnected must be installed.
Due to containing combustible material which may lead to fires spreading, all cabling should not go over a fire walls or barriers unless they are contained in fire resistant cable trays. These cable routes should also be given consideration in case they pose a threat to firefighters and all internal DC cable routs lengths should be minimal.
Procurement
There are a number of recommended requirements when appointing a contractor to install your solar PV system. This includes having and MCS Certification, BS EN ISO 9001:2015, be an a SSIP registered member (CHAS for example), have proof they are competent for DC, low voltage AC and high voltage systems. They should also hold the appropriate level of insurance including indemnity protection to cover the scope of work.
References and previous experience such as case studies, and a full list of key people involved in the project and their competencies should also be reviewed before an installer is appointed.
Inspection
If a subcontractor is used, then it is up to them ensure all of the equipment meets the requirements in the design, this includes DC connectors and compatibility. Some ratings may not be easily displayed.
The system should be checked at regular periods during the installation, and all cable containers should be checked for sharp edges to ensure they do not damage cables over time. Covered containers should be used to protect DC cabling from UV light as this may degrade the cabling over time.
Testing and commissioning
All testing and commissioning should be carried out in accordance with the IET PV Code of Practice requirements and as outlined in BS EN 62446-1:2016 and if module-level power electronics are used I the system, the engineer should seek guidance from the manufacturer.
Handover and documentation
Once the installation is complete and commissioned a handover pack containing all relevant documentation and information regarding the system is to be provided to the customer. Instructions on how to use the system will also be given to the person responsible for the system. The handover pack will also contain all relevant health & safety documentation as required by the CDM regulations.
Operation and maintenance
The Solar Energy UK O&M document recommends that commercial solar PV systems are inspected annually by a competent person.
The more a solar PV system is checked the lower the risk of fire as undetected faults can often lead to fires. All maintenance should be carried out as per the recommendations in the IET PV Code of Practice. A technical report by the IEC showed that 33% of reviewed PV fires were caused by product failure so it is important that early-stage symptoms of failure are reported.
Live online monitoring of systems an error detection systems are available and make it easier to check system performance and detect faults. Typically, IT departments need to be consulted in order to get the communication equipment implemented so such data can be transmitted.
Installations with a low pitch where self cleaning is not as effective should have regular cleaning scheduled. Panels with a build up of dirt and bird droppings can also pose a risk of fire by creating hot spots and overheating.
Insurers will expect a regular cleaning program for all commercial PV installations, carried out by a competent person who knows the risks associated with panel cleaning. Using in-house teams without the correct knowledge may result in electrocution.
All solar PV systems should be inspected for damage after a storm or extreme weather.
Provisions for the Fire and Rescue Service
Access for fire and rescue services should always be considered with enough space allowed for high reach vehicles and pumping appliances to gain access to buildings where PV modules are situated. If it is a large installation, the fire service should be invited to visit the site to familiarised themselves with the property and PV installation.
Information regarding the solar PV system should be made available to the fire and rescue services and include information on, the layout of the site and the solar PV locations, the location of the isolation switches, the location of main consumer units, the location of the indicator panel of the automatic fire detection system, details of ventilation systems, hazardous substances, and location of hydrants. ‘PV on roof’ signage should also be clearly displayed on buildings as its not always visible from ground level.
To comply with BS EN 7671 or to meet insurance company requirements, switches should be provided so that firefighters can remotely isolate the DC site of the PV system, ensuring the safety of the firefighter personnel. Such switches should be tested during routine maintenance and results recorded. These switches should be placed in safe locations and are in addition to the AC and DC Isolation switches.
To help mitigate risk and with the introduction of RC62, we now recommend that all companies opt for a SolarEdge solar PV system due to the fire safety functionality included with their technology.
If there is a fire, it is important that installers, maintenance engineers, and the emergency services are able to reduce the DC to a safe voltage when the AC is turned off.
Their Safe DC feature reduces the risk of working around damaged cables and automatically switches into safety mode when AC is shut down. There is still high voltage in the wiring when traditional inverters are shut down.
The SolarEdge system includes a firefighter gateway which makes it easier for the emergency services to isolate and shut down the solar PV system in the event of a fire, even if the system has not been the cause of the fire.
When there is a fault detected at the panel and no communication is being made between the inverter and the power optimiser on the panel, the default output voltage for each optimiser is set to 1V per module.
The SolarEdge inverters are designed to identify arc detections and shut down. This will prevent any fires occurring as a result of the arc. Arcing can occur when there are defects in the cables or the cables are not connected properly. It can also happen when cables degrade over time or when animals chew them.
If you would like to find out more about RC62 and how we ensure our solar PV installations comply to its recommendations and guidance, please get in touch.
© Copyright 2024
