In order to determine the hazards for objects of historical or artistic value, the light and ultraviolet doses produced by 12 different commercial electronic flashguns and 14 different photocopiers were measured. At 1 m distance the ultraviolet doses produced by the flashguns in the spectral region between 300 and 400 nm ranged between 0.062 and 1.55 J/m² and the light doses ranged between 0.58 and 6.08 klux s, corresponding to guide numbers of respectively 24 and 78. The ultraviolet doses were compared to the ultraviolet dose reached by one hour's illumination at 50 lux by a tungsten incandescent lamp, the internationally agreed light standard for sensitive materials. Between nine and 220 flashes (average: 50) could be made at 1 m to reach this dose. Taking into account a distance of 2-5 m and considering the average number of photographs of wedding ceremonies taken at town halls in a week (700), this amounts to approximately three-six hours of illumination at the 50 lux light standard. The ultraviolet doses measured at the glass plate of the investigated photocopiers ranged between 0.12 and 3.80 J/m² per exposure. Between four and 117 photocopies (average: 26) could be made to reach an ultraviolet dose equivalent to the one reached by one hour's illumination at the 50 lux light standard. With all flashguns and one photocopier, fitted with xenon flashtubes, high maximum light intensities were reached, up to 120 times the average intensity of sunlight at noon during summer at our latitude for the photocopier. As little is known about the special effects of high intensities on materials, care should be taken when interpreting the results of light and ultraviolet measurements in terms of damage. To minimize the amount of damage to valuable objects, the use of photocopiers provided with xenon flashtubes should be prohibited. Flashguns should be provided with an ultraviolet filter, absorbing at least 90% of the radiation between 300 and 400 nm. -- AATA -- CAL