As of January 1, 2014, all lacrosse balls used for play MUST meet NOCSAE standards and include the words "Meets NOCSAE Standard".
NOCSAE, the National Operating Committee on Standards for Athletic Equipment, commissions research in sports medicine & science and establishes standards for athletic equipment.
All three governing bodies for lacrosse in the United States – US Lacrosse, the NCAA and the NFHS - have agreed to mandate that only balls marked as "Meets NOCSAE Standard" will be allowed for use in games.
Additionally, the process of visually identifying these NOCSAE balls will become much easier. Beginning in January 2014, the only balls deemed legal for play will be those that state "Meets NOCSAE Standard" in type size that will be simple for consumers and game officials to read.
NCAA Lax Rules Editor: Only NOCSAE-approved balls are legal, the 'NCAA-approved' balls are not. There is a difference in construction manufacturing between the two.
Why is a standard really needed? The core issue involved in the approval of any equipment standard is safety. Adherence to a ball standard is a matter of quality control. The properties of all lacrosse balls (ie-weight, density, size, etc.) must be consistent to protect the integrity of other protective equipment, such as the facemask, helmet and eyewear, used in the game and to minimize risk to the participants.