Fire safety risks associated primarily with charging  electric mobility scooters have led to several serious  fires and raised concerns, says Adair Lewis, who  offers practical safety tips for this mode of transport.

NEW FORMS of transport often follow innovations in technology, but not all are adopted for daily use or are embraced by the population at large. For example, the innovative design of the Mary Rose may well have been a contributory factor to it falling over early in its career. The magnetic levitation train ran into the buffers before arriving at its first station and the much loved Concorde met a fiery end. Recently, more basic technology has led to the development of the mobility scooter, which although it may not yet be universally loved, has a proud and useful social role. With an estimated number in excess of 330,000 now in use in the UK, this relatively new form of transport has arrived and is definitely here to stay.

Mobility scooters are not for everyone, the government rules1 make it clear that unless you are disabled, you can only drive a mobility scooter if you are demonstrating the vehicle, training a driver or involved with its maintenance and repair. They would therefore perhaps better be termed ‘disability scooters’.

There are three classes of these vehicles that are variously known as motorised wheelchairs, scooters or buggies. Class 1 is a manual wheelchair, either self propelled or pushed by a companion. These devices are not the subject of the present discussions, they have no form of stored energy and do not appear to present problems to fi re risk assessors.

Class 2 scooters have three or four wheels and are powered by electric motors. They are steered using a bicycle style handlebar and designed for indoor or outdoor use on footways only. They are restricted to a maximum speed of 4mph and, as they are not required to have lights, they have minimal electrical wiring.

Class 3 scooters also have three or four wheels, but are intended for outdoor use with speed limits of 8mph on roads and 4mph on footpaths. As these are road vehicles, they should be registered with DVLA and are subject to rules 36 to 46 of the Highway Code. Somewhat curiously, the driver is not required to have a driving licence, although there have been calls for some form of test, following several accidents. Norfolk police is leading a campaign for improved driving standards and safety with road going mobility scooters. It is also rather strange that although used on the road, there is no mandatory requirement for drivers of Class 3 scooters to be insured.

Charging risks

By now you may be wondering: what has this got to do with fire safety? The main reason is that they are powered by batteries and thus have to be charged by connection to the mains electricity supply. Mobility scooters are typically powered by 10V or 12V batteries; many are powered by lead acid batteries of the type used in conventional motor cars, but nickel metal hydride and lithium ion batteries can be found in newer machines. The latter are particularly suited for this purpose as they have high energy density, giving greater ranger or longevity of use between charges.

The need for charging is of direct concern to fire risk assessors and sadly, in several cases, to fire investigators. Several dramatic fires have been reported and no doubt many smaller incidents have gone with little notice.

In Melton Mowbray, a mobility scooter is reported to have burst into flames, seemingly without warning. Luckily, the driver’s carer happened to be in the immediate vicinity and provided life saving assistance to the driver, who would not have been able to escape the flames unaided.

In South London, there was a fire on the ground floor of a block of flats with a single staircase. Fire investigators found that the occupier of the ground floor flat had brought his scooter into the entrance hall in order to charge the battery. He had then run the charging lead beneath his front door and plugged it into an extension lead supplying power from a socket in the living room. It was only by good fortune that all occupiers of the flats on the upper floors escaped or were rescued by the fire service, and no lives were lost.

In a third example in Banbury, an electrical fault led to the death of two residents after a mobility scooter had been brought into the hallway of their home to be put on charge overnight.

Fire safety concerns with buggies have focused on their powerful batteries with associated wiring to lights, beacons and the like, together with the significant amount of combustible materials that are associated with the vehicles. The seat, for example, may be constructed of hard plastic; but the need for comfort during long trips has led to the introduction of upholstery covered with either vinyl or fabric. The materials used depend on various factors such as comfort, water resistance and ‘slipperiness’ of the seat. No reference has been seen to fire resistance influencing the design. Road going buggies are often seen in bad weather enclosed with plastic and fabric enclosures to provide shelter from the elements; these are also likely to be combustible.

BRE research

To investigate exactly what happens when mobility scooters are involved in a fire, the Building Research Establishment (BRE) undertook a research project in 20152 to investigate the heat release and smoke production from two examples of these devices. Those selected were deliberately of unknown make and model, but from the photographs and video they appear to be of a Class 2 design, which means that they were likely to be lighter and incorporate less combustible upholstery than some larger Class 3 machines.

The test rig was built to simulate two scooters located one behind the other in a corridor and to allow the formation of a smoke layer. A fire was started in the front scooter using a heptane soaked strip of low density fibreboard placed on the charging point.

A video of the test burn is available on the BRE website (www. bre.co.uk). The fire developed very rapidly and spread to the second scooter in about three minutes. The fire was extinguished after 7.5 minutes, as the temperature at ceiling level was by then reaching 1000oC and there was a heat release rate of some 2500kW. At the time that the fire was extinguished, the total heat released was approaching 450mJ, but even then a significant amount of unburnt upholstery was still in position on the remains of the scooters.

Although the figures for the temperatures and heat release are impressive, in practice the principle danger is not so much from the heat as from the copious volumes of smoke and noxious gases that are produced with a potential to spread throughout a building unless effective fire compartmentation is in place. In many sheltered housing schemes, there would be just two or three minutes before serious problems would be present, especially as the presence of mobility scooters means that people with a disability will be present in the building. This emphasises the need for effective staff training, briefing of residents and evacuation drills. The material in the report and video should be considered for use as the basis for a staff training session wherever mobility scooters may be present.

There are many practical lessons that should be learned to reduce the risk in premises where residents use these scooters. Very few existing flats were designed or built with mobility scooters in mind and thus safe charging areas are not provided and the design does not allow easy conversion to allow their safe use. Many social housing providers, however, are now well aware of the problem and are addressing this in new build properties.

Practical lessons

Good practice dictates that the following should be observed:

  • areas should be provided specifically for the storage and charging of mobility scooters – they should not be used for other forms of storage
  • a sufficient number of socket outlets should be provided in the charging area and extension leads should not be used – consideration should be given to controlling the electricity supply to the chargers via a timer or timing circuits to prohibit charging operations during sleeping hours
  • buggies should only be charged using the charger supplied for this purpose and in accordance with the instructions of the manufacturer – other forms of charger must not be used – and chargers should be subject to periodic inservice portable appliance inspections (PAT tests)
  • charging areas should be provided with low and high level ventilation • where a buggy room is provided within living accommodation, it should be accessible directly from the outside with level access
  • doors from the outside should be sufficiently wide to allow easy access and turning into the roomwhere necessary, for security reasons a form of electronic access control such as a proximity card reader may need to be provided to release the external door
  • the form of construction of the buggy room should provide at least 60 minutes’ fire resistance between the charging area and other parts of the building
  • where there’s an interconnecting door between the buggy room and another part of the building, this should also provide at least 60 minutes’ fire resistance
  • where a buggy room is provided in a detached structure, this should be of noncombustible construction and ideally be situated at least 10m from the living accommodation
  • automatic fire detection should be provided in charging areas

Policy provision

Providers of sheltered housing and similar accommodation should have a policy relating to the use and charging of mobility scooters in each of their premises. They should also liaise with their insurers with regard to these provisions. The maximum number of scooters that may be safely stored and charged in the buggy room should be recognised in these plans. The demand for provisions for mobility scooters is now such that some housing providers have to control their numbers on a ‘first come, first served’ basis, with a waiting list of residents who wish to purchase a scooter.

It is not unusual for fire risk assessors to encounter buggies that have been brought into a building and taken to upper floors in a lift. The introduction and movement of buggies within a building should be in compliance with the housing association or provider’s policy. Class 2 scooters are smaller, lighter and more manoeuvrable than road going devices and may be allowed into buildings provided the organisation’s rules are observed. No buggy, however, should be left parked, even temporarily, in an escape route or other circulation space where they may form an obstruction or potential source of ignition. Buggies should never be charged in escape routes.

Further information relating to the charging of buggies and other forms of electric vehicles is set out in RC59: Fire safety when charging electric vehicles3.

Mobility scooters are not going to go away; they are a novel form of transport that is here to stay. Wherever they are present, they must be addressed in the fire risk assessment for the premises, carried out in compliance with fire safety legislation. They need somewhere safe to be housed and charged, and they need to be managed so as not to present a fire hazard to their owners or others in the neighbourhood.

Adair Lewis is a technical consultant for the Fire Protection Association.


Footnotes

1. www.gov.uk/mobility-scootersand- powered-wheelchairsrules/ vehicle-tax-registrationand- insurance

2. Heat release and smoke production from burning mobility scooters, BRE Trust Project 232-14- RM, 2015, Building Research Establishment

3. RC59: Risk control: Fire safety when charging electric vehicles, 2012, published by the Fire Protection Association on behalf of RISCAuthority

 

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