I describe two methods for studying hadronic backgrounds to prompt photon
production with L3, and compare the observed background rates with Monte Carlo
predictions. I find that the Monte Carlo models JETSET and HERWIG underestimate
the production of isolated neutral hadrons in hadronic Z decays at LEP. By
extrapolating results obtained with L3, I estimate that the rate of
prompt-photon + jet background to a H -> gamma gamma search at the LHC will be
larger than Monte Carlo predictions by a factor of 1.5-2.5.Comment: 4 page