This article is supposed to aid an Eruv checker who is examining for Karpefs, to give him a sense of the size of 5,000 Square Amos.

A Karpef is an area which is not fit for human habitation and could render not useable a what otherwise would be a Kosher Eruv. However, A Karpef only invalidates an Eruv when it is large enough.

Identifying a Karpef is a complicated task.   You should consult with your Posek about what types of areas are considered a Karpef.  Common potential Karpefs are cemetaries, swamps, flower farm, and lakes. To learn more, refer to The Curious Case of the Karpef.

After knowing what possibly is considered a Karpef, the potential Karpef is a problem when it is bigger than 5,000 Square Amos.   (There are different opinions on how big an Amah is.  For the purposes of this article, we assume a Karpef is 20,000 square feet.)

If a Karpef is 20,000 square feet   (We say “If” because the size of a Karpef is dependent on which opinion you are using for the length of an amah)…

Then a Karpef is close to the size of….

  • .46 of an Acre
  • Half a football field
  • Three tennis courts side-by-side (including the section between the actual court and the outer fence)
  • About 4.5 NBA Basketball courts
  • A little bit bigger than a NHL sized hockey rink
  • 120 standard size parking spots side by side
  • Most Parking lots with two aisles (at least 20 parking spots per row)