Editing O scale (section)

====Scale====
Scale is the ratio of a model dimension to the real life dimension. O Scale in the UK is commonly 1:43.5 or 7&nbsp;mm to the foot. In continental Europe it is commonly 1:45. 1:43.5 is also used, particularly in France.<ref name="NEM-010">{{cite web|url=http://www.morop.org/fr/normes/nem010_f.pdf|title=Normes Européennes de Modélisme: Rapports de réduction, échelles, écartements|year=2004|publisher=Union Européenne des Modélistes Ferroviaires et des Amis des Chemins de Fer|language=FR|access-date=2010-04-11}}</ref> In the USA, 1:48 is common.<ref name="NMRA S-1.2 2009.07"/> The [[National Model Railroad Association|NMRA]] and the [[MOROP]] maintain detailed standards for a variety of scales to help model makers create interoperable models.<ref name="NEM-010"/><ref name="NMRA Intro">{{cite web
 |url          = http://www.nmra.org/standards/standards.html
 |title        = Standards & Recommended Practices - Introduction
 |date         = 2008-02-17
 |author       = T.J. Klevar
 |access-date  = 2010-04-11
 |publisher    = [[National Model Railroad Association]]
 |url-status   = dead
 |archive-url  = https://web.archive.org/web/20100403082408/http://www.nmra.org/standards/standards.html
 |archive-date = 2010-04-03
}}</ref>