Once the skin is exposed to UVR, cells deep in our skin called melanocytes initiate a process whereby more melanin is produced. This subsequently browns as it rises to the skin’s surface, producing either a direct pigmentation (UVA) or indirect pigmentation (UVB) tan. UVA and UVB both contribute to tanning of the human skin. UVA is the dominant tanning ray, which produces the golden tan, while UVB can cause the skin turning red and develop a sunburn. Sunbed lamps simulate the sun and emit UVA and UVB but they go a stage further and control the output with a balance of UV to minimise the risk of burning and maximise the tanning.
To date, no difference has been detected between the reaction of our skin to artificially generated radiation and solar radiation of the same composition. The sun emits various types of ultraviolet radiation in the form of A, B and C waves of specific wavelengths. Sunbeds only emit “UVA” and “UVB”, which are also the only ones from sunlight that reach our skin (UVC waves are absorbed by the Earth’s ozone layer). While sunbeds’ irradiance spectrum (ratio between the two types of UVR) is constant, the sun’s varies according to your geographic location and to the season (the Earth’s inclination to the sun). Therefore a sunbed’s irradiance is similar to that of the sun in terms of composition, but not in terms of UVA:UVB ratio, as this ratio differs in every place on Earth. By contrast, the spectrum emitted by a sunbed remains stable whereas it is not always obvious to people how “strong” the rays from the sun are, as they vary depending on the time of day, season and location.
As sunbeds’ irradiance presents similar characteristics to sunlight, it can also entail similar adverse effects. Hence, as for the sun, excessive accumulation and/or a too long exposure can result in sunburn and also increase the risk of developing skin cancer. Similar to the general recommendation to avoid sun exposure at peak time or for prolonged duration, in particular during summer, for safe tanning it is recommended to use sunbed sessions of moderate length, with sufficient time between sessions. Controlled exposure to UV, either from sunlight or on a sunbed, is important to avoid over-exposure and sunburn.
A sunbed provides the same essential benefits as natural sunlight: it induces Vitamin D production, which is essential for good health. A form of cholesterol naturally found in your skin absorbs the UVB radiation and gets converted into pre-vitamin (cholecalciferol) which, once metabolized, turns into Vitamin D. How much Vitamin D is produced depends upon age, the amount of pigment in the skin and the amount of time for which the skin was exposed. Even the intensity and wavelengths of the UV radiation and the amount of uncovered skin have an effect. Vitamin D is typically good for strong bones and teeth and plays an important role in maintaining resistance. It is also important for the prevention of osteoporosis and it also decreases the risk of fractures in older women.
Among other initiatives, the ESA has participated in the works of the Technical Committee on “Photobiology and Photochemistry” of the International Commission on Illumination (CIE). The Committee produced a report in 2011 addressing the issue of sensible exposure to solar ultraviolet (UV) radiation.
The European Sunlight Association has cooperated with CENELEC (one of the main European standardization bodies) and the Austrian Standards Institute (ASI) to develop of a new European Standard on training & service provision for sunbed operators.
Last but not least, other effects, which may be less measurable but are quoted by users include: sunbeds can make people feel better and improve their mood, in particular for those who by their place of residence, lifestyle or occupation only have limited exposure to natural sunlight.
In tanning there is no ‘one-size-fits–all’. The amount of UV exposure needed to acquire a tan varies according to your skin type. Hence, the fairest skin type cannot tan without burning and should not use a sunbed while darker skin types are less likely to burn. That is why tanning professionals are trained to determine the appropriate amount of UV exposure for each client while minimising your risk of sunburn.
The following table identifies skin types and the corresponding recommended tanning practice.
In order to avoid any risk of burns and to reduce the likelihood of damage to the skin due to long exposure, the EU adopted a mandatory standard in 2007 (EN 60335-2-27) limiting the irradiance of sunbeds to 0.3 W/m2. Put differently, a sunbed session shall have a maximum UV output that corresponds to the mid-day, Mediterranean sun (UV index of 12).
As the risks related to irradiance cannot be dissociated from exposure time, all sunbeds include a time control system (30 minutes maximum, after which a sunbed automatically switches off) to prevent excessive exposure.
Finally, as the risk of sunbed use has also to be considered on the basis of each person’s skin type, many sunbeds or tanning facilities are equipped with a skin scanner system to assess the type and duration of tanning to suit consumers’ needs in a safe manner.
As the safe sunbed use is critically dependent on the way the service is provided, various standards exist to guarantee that operators of professional UV indoor tanning facilities are properly trained to take clients’ characteristics into account and to provide all necessary information and guidance prior to any tanning session. You can find further information on the website of your country’s national association of the indoor tanning industry.