Scienceware* Nonradioactive Markers

Normal Energy Level: The nontoxic phosphorescent material used in this pen is ideal for marking various substrates that are to be radiographed with run numbers, dates, exposure times, film alignment markings, etc. Bright green markings, which do not glow in the dark, are visible under normal conditions and will show on X-ray film. The nonradioactive energy emitted by this pen may be adjusted by exposure to normal incandescent or fluorescent white light. A three- to four-minute energy emission leaves a distinct impression and will not overexpose the film. 5600 Angstrom spectral peak.
High Energy Level: This pen has a slightly higher signal emission strength and a slightly longer duration signal emission time than the normal. Marks X-ray film and works well when film responsiveness is lowered and the film is chilled. The mark emits only visible light, therefore no beta or other isotope emission occurs.