[BillyMac]

Edit: thedewed: I just realized that you asked for college. This is for NFHS. Ignore if not helpful. Some of the college guys will be along shortly.

Rule 4 - Section 40 - Screen
ART. 1 A screen is legal action by a player who, without causing contact, delays or prevents an opponent from reaching a desired position.
ART. 2 To establish a legal screening position:
a. The screener may face any direction.
b. Time and distance are relevant.
c. The screener must be stationary, except when both the screener and opponent are moving in the same path and the same direction.
d. The screener must stay within his/her vertical plane with a stance approximately shoulder width apart.
ART. 3 When screening a stationary opponent from the front or side (within the visual field), the screener may be anywhere short of contact.
ART. 4 When screening a stationary opponent from behind (outside the visual field), the screener must allow the opponent one normal step backward without contact.
ART. 5 When screening a moving opponent, the screener must allow the opponent time and distance to avoid contact by stopping or changing direction. The speed of the player to be screened will determine where the screener may take his/her stationary position. The position will vary and may be one to two normal steps or strides from the opponent.
ART. 6 When screening an opponent who is moving in the same path and direction as the screener, the player behind is responsible if contact is made because the player in front slows up or stops and the player behind overruns his/her opponent.
ART. 7 A player who is screened within his/her visual field is expected to avoid contact by going around the screener. In cases of screens outside the visual field, the opponent may make inadvertent contact with the screener and if the opponent is running rapidly, the contact may be severe. Such a case is to be ruled as incidental contact provided the opponent stops or attempts to stop on contact and moves around the screen, and provided the screener is not displaced if he/she has the ball.
ART. 8 A player may not use the arms, hands, hips or shoulders to force his/her way through a screen or to hold the screener and then push the screener aside in order to maintain a guarding position on an opponent.