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We explore the relative strength of the narrow emission lines in a Sloan Digital Sky Survey based sample of broad Hα selected active galactic nuclei (AGN), defined in Paper I. We find a decrease in the narrow to broad Hα luminosity ( L  bHα ) ratio with increasing  L  bHα , such that both    L  (   [  Oiii   ]λ  5007  )    and    L  (    narrowH  α    )    scale as    ∝   LbH   α0.7for10  40   &lt;   L    bH   α    &lt;   10  45ergs   −  1. Following our earlier result that  L  bHα  ∝  L  bol , this trend indicates that the relative narrow line luminosity decreases with increasing  L  bol . We deriveL   bol    /   10  43ergs   −  1    =  4000    (  L   (   [  Oiii   ]   )   /   10  43ergs   −  1    )    1.39. This implies that the bolometric correction factor,L   bol    /  L   (   [  Oiii   ]   )    , decreases from 3000 atL   bol    =   10   46.1ergs   −  1to 300 atL   bol    =   10   42.5ergs   −  1. At low luminosity, the narrow component dominates the observed Hα profile, and most type 1 AGN appear as intermediate type AGN. Partial obscuration or extinction cannot explain the dominance of intermediate type AGN at low luminosity, and the most likely mechanism is a decrease in the narrow line region covering factor with increasing  L  bol . Deviations from the above trend occur in objects with  L / L  Edd  ≲ 10 −2.6 , probably due to the transition to LINERs with suppressed [O  iii ] emission, and in objects with  M  BH  &gt; 10 8.5  M ⊙ , probably due to the dominance of radio‐loud AGN, and associated enhanced [O  iii ] emission.

Type 1 AGN at low z – II. The relative strength of narrow lines and the nature of intermediate type AGN