Saunas
BACKGROUND
Saunas are increasingly encountered in a wide range of premises such as hotels, health clubs, leisure centres and similar facilities; also, in the high-net-worth residential sector. They should be classified as a hazardous feature owing to the combustible construction, furniture and finishes employed, combined with potential ignition sources.
Saunas provide a dry heat (typically within the range of 80 -105⁰C), traditionally by the use of electric, gas or wood burning stoves incorporating stones from which humidity is provided by the manual application of water by the user or, in the case of modern units, by automatic water injection. Various types of purpose designed electric heating units are available. These include both floor- and wall-mounted units and wall-mounted units that can be concealed behind removable benches. Some heaters are constructed with a cool-wall outer casing.
In addition to traditional electric heaters, infrared sauna heaters have in recent years been developed which provide a direct method of heating rather than via the air. These operate at much lower ambient temperatures (normally around 40 - 60⁰C). As a consequence of the lower operating temperatures and the absence of any requirement for water facilities in the cabin, along with low power requirements, infrared heated saunas can be located almost anywhere and tend to have lower energy costs.
Typical sauna cabins with traditional electric heating
Typical electric sauna heaters
A typical wood burning sauna heater
A gas fired sauna heater
An infrared heated sauna
The above image shows a typical arrangement of electric infrared heating
elements behind a steel mesh with further protection for the user in the form timber slats. This form of heating typically operates at a maximum temperature of circa 50⁰C, and a distance of at least 50mm is normally incorporated between the heater surface and the protecting horizontal slats, which under normal circumstances is considered sufficient to provide adequate protection to the skin and eliminate the risk of thermal degradation of the timbers.
Saunas employing the latest non-luminous, infrared heating panels.
LOSS EXPERIENCE
There have been many serious fire losses attributable to saunas, headline news examples of which include:
More than 200 people evacuated from a historic building after a fire broke out in the sauna of a private members' club on Pall Mall, London SW1.
Gym-goers and residents evacuated from a housing complex in Watford after a sauna set on fire.
The sauna in the Ice Factor in Kinlochleven completely destroyed in a fire and much of the rest of the building severely damaged by smoke. Around twenty fire crewmen spent more than five hours battling to bring the blaze under control.
The principal causes of fires in saunas are centred on the heating unit and commonly include:
Electrical faults or defects.
Failure of temperature controls or operating at an excess temperature, resulting in overheating and thermal degradation of the timber cladding and furnishings.
Users interfering with thermostats.
Towels, paper cups and other litter coming into contact with the heater, arising from poor facility management.
Heaters incorrectly installed or not maintained in accordance with the manufacturers’ instructions.
Heaters overheating as a result of using incorrect or insufficient stones or packing stones too tightly.
Use of undiluted flammable essences on the heater stones.
Additional hazards are presented by gas fired and wood burning heaters owing to the need to provide additional thermal protection around the heater and at the flue exit point. Gas fired heaters are normally only encountered in large commercial installations, and wood burning stoves tend in the main to be limited to external sauna cabins.
RISCAUTHORITY RC50 – FIRE SAFETY IN THE CONSTRUCTION AND USE OF SAUNAS
In response to concerns from member Insurers, RC50 was published in 2009 and provides comprehensive guidance on fire safety controls in respect of the construction and use of saunas. This document gives recommendations under the following headings:
Construction
Heating and electrical installation
Fire protection
Fire safety management
Some of the key fire safety measures in RC50 are summarised below:
The fire risk assessment for the premises to include close attention to the sauna facility.
The sauna should be located in a room or compartment proving at least 60 minutes fire resistance.
All electrical installations and equipment should be installed, inspected and tested periodically by a competent electrical contractor, and designed, manufactured and approved for use in a sauna environment.
(BS 7671: Requirements for Electrical Installations includes special provisions for saunas (Section 703) which includes the specification of temperature zones governing the types of electrical equipment installed.)
The sauna heater should be installed in accordance with the manufacturer’s instructions, with particular attention given to ensuring that specified minimum distances from the heater and all timber surfaces are observed.
(All heater manufacturers provide details of minimum clearances which can differ widely, depending on the type and heat output of the appliance. As a further protection measure, timbers in close proximity to the heater may on occasions be lined with a fire resisting material. However, reference to leading sauna companies would indicate that subject to the heater being installed, operated and maintained in accordance with the manufacturer’s instructions, such protection should not under normal circumstances be required.)
A high temperature limit switch should be installed to isolate the heater in the event of thermostat failure.
(Most modern commercial saunas will have an externally located electronic control panel in which an inbuilt “overheat protector/temperature limiter” will normally be incorporated).
Sauna heaters should be serviced by a competent person in accordance with the manufacturer’s instructions.
Consideration should be given to the installation of an automatic fire suppression system where determined by a risk assessment.
Prompted by the concerns of Insurers, several UK fire protection companies have each developed a cost-effective water mist system marketed for the protection of saunas. These systems which can easily be retrofitted to an existing facility are as follows:
1. Saunasafe, by Marlowe Fire and Security (previously Flamefast) - https://marlowefireandsecurity.com/solutions/fire-suppression-systems/sauna-fire-suppression/. System third party tested and approved by the Danish Fire Laboratories (DFL) and endorsed by Zurich Risk Engineering.
2. Hydramist, by Watermist Ltd - www.watermist.com/en/applications/. System tested and certified to CEN TS 14972: 2011 Fixed firefighting systems - Watermist systems - Design and installation. (The Hydramist 15AMPU fire suppression system was the first water mist system to gain LPCB approval under LPS 1223: Requirements and Testing Procedures for Approval of Fixed Fire Extinguishing Systems for Catering Equipment. Whist the hardware employed for the protection of saunas may be similar, the LPCB approval obtained by Watermist, by design, solely relates to the protection of catering equipment on which fire tests have been conducted).
3. SmartMist, by Smartmist Systems Ltd - https://www.mistingsolutions.co.uk/smartmist-sauna/
Another vital control measure relates to the need to ensure that correct fire safety inspections of the sauna are carried out by persons with suitable training and that all such inspections are formerly recorded.
R is aware of a number of sauna fires attributable to towels being left in close proximity to the heater at the end of the day, which were subsequently ignited when the sauna was automatically switched on the next morning. RC50 recommends that the practice of automatically switching sauna heaters on when the facility is unoccupied is avoided.
Key fire safety checks should as a minimum include those items set out in the Appendix to this Technical Bulletin.
HEALTH & SAFETY
Many local authorities in England (under Environmental Heath) operate a policy of special treatment licensing for establishments containing a sauna (other treatments covered by licensing can include steam rooms, massage, manicure, chiropody, light and electric treatments). Depending on the policy of the local authority, licence applications, both initially and upon renewal every 12 months, are most likely to involve an inspection of the facility by an Environment Officer with the objective of ensuring compliance with the local authorities’ conditions of licensing.
Common licensing requirements applicable to saunas include the following:
Use of sauna restricted to persons over the age of 16. (Persons of 13yrs+ can use the sauna if accompanied by a parent or guardian).
Staff should be suitably trained and competent to carry out all duties and responsibilities in an approved manner.
A full client consultation should be carried out at the time of the first visit, prior to entering the sauna. Where this is impractical such as is likely to be the case with a sauna in a hotel, adequate health information must be displayed, including covering health conditions that increase the risk of adverse reactions when using the sauna.
A thermometer shall be provided indicating the temperature inside the sauna, together with a clock or other timekeeping device visible to the users.
Sauna door to incorporate a glazed panel allowing safe access and egress by users and supervising staff.
The temperature control device shall not be accessible to the users of the sauna.
A notice providing accurate information on the safe use of the sauna must be displayed.
A non-verbal alarm system (panic button) linked to a manned reception area shall be provided and the licensee shall have a written policy detailing the action to be taken on alarm activation.
The sauna must be cleaned and disinfected each day, in accordance with the manufacturers’ instructions and with cleaning materials specified by the manufacturer.
The hot stones in the sauna to be protected by a guard rail or barrier.
The electrical safety of all equipment shall be examined periodically by a competent engineer and electrical equipment serviced in accordance with the manufacturer’s instructions.
Daily, weekly, monthly and periodic cleaning and maintenance records must be available for inspection.
Irrespective of whether a special treatment licence applies, the above criteria shall be considered established best practice for managing the health and safety risk in sauna facilities, which together with the key fire safety measures previously detailed, should be considered by all Consultants.
SURVEY EXPECTATIONS
Where saunas are encountered, it is important that Consultants pay close attention to the inherent hazards presented and the risk control measures in place by conducting an internal inspection of the facility, together with appropriate enquiries of the management, where necessary seeking formal confirmation of key measures by observing inspection records, written maintenance schedules etc.
Particular attention should be given to checking on the housekeeping around and under benches and to observing any scorching or overheating of the timber linings or furnishings, including the timber guard which is commonly present around the heater. In the event that charring is evident, suitable risk improvements should be raised, based around the RiskSTOP standard wordings.
Details of the sauna are to be included in the survey report, including the method of heating and any active or passive fire protection measures which may be encountered.
In cases where, at the time of survey, the sauna was in use and access not possible, it is essential that reference to this is made in the report making it abundantly clear to the Underwriter that an internal inspection of the sauna could not be conducted.
The major benefits of installing a fire suppression system, such as the water mist systems detailed above, must not be overlooked and a risk improvement raised where merited. Ignoring all other aspects, a risk improvement calling for sauna fire suppression for premises with a combined MD/BI exposure of £5m and over is considered the normal default position.
Under normal circumstances this should be raised as a recommendation, although occasions may arise where the risk is such as to make this a requirement, particularly when conducting a survey post loss.
In sprinklered premises, active protection is to be achieved by the extension of sprinklers into the sauna cabin, employing heads of an appropriate rating.
SAUNAS – FIRE SAFETY MANAGEMENT CHECKLIST
Start of day inspection
Sauna visually in sound condition with any benches, backrests and boards undamaged and correctly positioned.
Sauna heater and guard (where fitted) undamaged and secure.
Sauna free from combustible materials such as towels, paper cups and general litter.
Timbers in the vicinity of the heater and light fittings free from signs of scorching or other evidence of overheating.
Thermostats and control equipment visually sound and free from tampering.
Electrical connections visually undamaged.
Water mist fire suppression system (where installed) checked for correct operational status, and discharge nozzles and detector points undamaged and free from foreign matter. Also, all isolating valves to the water supply are correctly secured in the operating position.
During the day (at two hourly intervals)
Benches, backrests and boards remain undamaged and correctly positioned.
Heater and sauna clear of towels and refuse.
Thermostats and control equipment not tampered with and showing correct status.
Sauna being used correctly including:
Sauna not being used by persons under the influence of alcohol or drugs.
Children under 16 not using the sauna unless accompanied by an adult.
Excessive or incorrect water usage exposing heating elements to thermal shock.
End of day inspection
Benches, backrests and boards remain undamaged and correctly positioned clear of heater.
Heater and sauna clear of towels and refuse.
Thermostats and control equipment not tampered with and showing correct status.
Timbers in the vicinity of the heater and light fittings free from signs of scorching or other evidence of overheating.
Power supply switched off and heater timer set to the off position.
All fire doors in the compartment walls separating the sauna from the adjacent areas remain closed.
All inspections are to be conducted by suitably trained, competent persons. Inspections are to be formally recorded and all defects and deficiencies remedied as appropriate. Records should be checked weekly by senior management.