Results from the test inserting a simulated emission line doublet at 2000 Å (rest frame) and recovering the line using Platefit at a significance of 3σ. The curves show fits for the lognormal cumulative distribution functions of the data assuming Poisson errors in the number of recovered objects. Numerical results for the flux limits at fixed completeness levels (90%, 75%, and 50%, normalized at an input line flux of 10^-16 erg s^-1 cm^-2) and using fixed detection thresholds (3σ in integrated doublet S/N) are shown in Table 1.