Number taboos in a Chinese elevator

This elevator panel image was sent to me by Nick Kaldis:

It's immediately obvious that floors 4, 14, and 24 are missing because:

sì 4 || sǐ 死 ("death")

The absence of 18 is not so easy.  It's because:

18 || shíbā céng dìyù 十八层地狱 ("eighteen levels of hell")

Note that the word for "level [of hell]", viz., céng 层, is the same as that for "floor [of a hotel or other multi-story building]".

For those who are interested in an exhaustive cosmology of Chinese hell, I highly recommend this virtuoso Wikipedia article, which has these sections:

Alternative names (21 more common different names)

Conceptions and terminology

Ten courts of King Yanluo / "King Yama" (यम राज/閻魔羅社, Yama Rājā)

Eighteen levels of Hell — each one described in two versions (e.g., Báshé dìyù 拔舌地獄 ["Hell of Tongue Ripping"] and Nílí dìyù 泥犁地獄 ["Naraka Hell"]) and as mentioned in the late Ming novel Journey to the West (Diàojīn yù ["Hell of Hanging Bars"])

For the heavily annotated translation of a medieval vernacular, prosimetric tale of a Buddhist saint who goes down to the terrifying depths of hell to rescue his mother, see the "Mùlián biàn wén 目連變文" ("Transformation text on Maudgalyāyana") in Victor H. Mair, Tun-huang Popular Narratives (Cambridge [Cambridgeshire] ; New York: Cambridge University Press, 1983).  For the judicial landscape of the Buddhist Chinese hell, see Stephen F. Teiser, The Scripture on the Ten Kings and the Making of Purgatory in Medieval Chinese Buddhism (Honolulu: University of Hawaii Press, 1994).

When I was studying Classical Chinese at the Middlebury Summer School in 1969, I stayed in the Delta Upsilon (ΔΥ) fraternity as a temporary dormitory.  Since we had a Chinese only pledge (we spoke Mandarin, not Classical Chinese, except when reciting old texts!), we had to come up with a Chinese name for the building we were staying in.  We called it "Dìyù táng 地狱堂" ("Hell Hall").  It was appropriately very hot that summer.

Selected readings

• "A medieval Dunhuang man" (7/17/23) — with valuable bibliography
• "Applied Quadrophobia" (11/14/17)

[Thanks to Zhaofei Chen]