guide board vs handrail

guide board

noun
  • Synonym of guardrail 

handrail

noun
  • A rail which can be held, such as on the side of a staircase, ramp or other walkway, and serving as a support or guard. 

  • A moving continuous belt-like rail on either side of an escalator which users can hold on to for support. 

How often have the words guide board and handrail occurred in a corpus of books? (source: Google Ngram Viewer )