The bulb you posted, mentioned Photogenic on the page, Photogenic is an old American lighting company, I got this off their web site http://www.photogenicpro.com/

PhotogenicŪ Professional Lighting was founded in 1904 in Youngstown, Ohio.
The company has a long established reputation for supplying high quality lighting equipment and light shaping accessory products for professional photographers..............

As has been mentioned, the flash tubes (bulbs) that you have are not coated to reduce UV emission.


Ralph