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Health hazard of UV irradiation

The Finnish Ministry of Social Affairs and Health has issued decree No: 1474 (Dec. 16. 1991) - which is in harmony with current CIE and ISO recommendations - with regard to the maximum exposure to non-ionising radiation. According to this decree, the biologically weighted effective energy density of ultraviolet radiation on eye or skin must not exceed 50 J/m2 per day.

The UV radiation of Active UVHeat exceeds this figure and it may therefore constitute a health hazard1). At a distance of 30 cm, the limit is reached in 80 minutes; at 1.5 meters in 780 minutes2). In the home, the Active UVHeat lamp must be shielded so that its light is screened from the areas where there are people for long periods of time. The terrarium must have a shaded area available for all animals at all times. The same risk is present also with other high output UV lamps. With other lamps, the estimated safe exposure time at 30 cm distance is about 1.5 hours. A single sheet of window glass secures adequate protection from harmful radiation. Such glass filters 22 % of UVA and 96 % of UVB radiation (Gehrmann, 1987).

1) Update: New data available. See Updates: Previously unreleased information.

2) Errata: In original printed article (as well as in the downloadable PDF) these values were reported only half of the corrected values here.