On deconstructed it stated that inside of florecent bulb needs to be hundreds of time lower pressure than atmospheric to vaporize mercury. Atmoshperic is 14.7 PSIA max vacum is 29.9"hg 2.03"hg equals 1 psi so at that point when pulling a negetive pressure can only be twice as low as atmospheric roughly speaking. science is awsome enough in it self with out dramtizing the figures.