Degrades bioactive fatty acid amides to their corresponding acids, with the following preference: N-palmitoylethanolamine > N-myristoylethanolamine > N-stearoylethanolamine > N-oleoylethanolamine > N-linoleoylethanolamine > N-arachidonoylethanolamine. H2O + N-hexadecanoylethanolamine = ethanolamine + hexadecanoate H2O + N-(long-chain fatty acyl)ethanolamine = a long-chain fatty acid + ethanolamine H2O + N-dodecanoylethanolamine = dodecanoate + ethanolamine H2O + N-tetradecanoylethanolamine = ethanolamine + tetradecanoate an N-acylsphing-4-enine + H2O = a fatty acid + sphing-4-enine H2O + N-hexadecanoylsphing-4-enine = hexadecanoate + sphing-4-enine H2O + N-dodecanoylsphing-4-enine = dodecanoate + sphing-4-enine Lipid metabolism; fatty acid metabolism. Heterodimer of an alpha and a beta subunit, produced by autocatalytic cleavage. N-glycosylated (PubMed:30301806). Tunicamycin treatment causes a reduction in specific activity against N-palmitoylethanolamine (By similarity). Autoproteolytic cleavage at pH 4.5 gives rise to the alpha and beta subunit (PubMed:30301806). Cleavage gives rise to a conformation change that activates the enzyme. The same catalytic Cys residue mediates the autoproteolytic cleavage and subsequent hydrolysis of lipid substrates (By similarity). Belongs to the acid ceramidase family. Intron retention.