Major League Baseball recommended teams have protective netting between the dugouts for any field-level seats within 70 feet of home plate.
The guidelines were announced Wednesday at the winter meetings following a season in which several fans were injured by foul balls, prompting MLB to study fan safety. Most teams are expected to expand their use of netting.
"It is important that fans have the option to sit behind protective netting or in other areas of the ballpark where foul balls and bats are less likely to enter," Commissioner Rob Manfred said in a statement. "This recommendation attempts to balance the need for an adequate number of seating options with our desire to preserve the interactive pre-game and in-game fan experience that often centers around the dugouts, where fans can catch foul balls, see their favorite players up close and, if they are lucky, catch a tossed ball or other souvenir. "
The recommendation also applies to spring training ballparks, many of them owned by municipalities.
"The recommendations strike a balance between providing a reasonable inventory of seats behind protective netting at each stadium while at the same time accommodating fans who desire seats with unobstructed access to players and on field activity," said Dan Halem, MLB's chief legal officer. "Both fan safety and fan choice are extremely important to MLB, and these recommendations reflect those principles."
Boston, the Los Angeles Dodgers and Philadelphia immediately said they will follow the recommendation. The Phillies hope to install thinner material that is less noticeable.
"We anticipate that such compliance will require us to expand our protective netting behind home plate about 10 feet in width on both sides," Philadelphia Chief Operating Officer Michael Stiles said. ""We understand that our fans differ in their opinions about sitting behind protective netting and we will do our best to accommodate those different preferences,"
Boston is "in the process of evaluating different design options to identify the best solution for Fenway Park and is proactively reaching out to the ticket holders most affected by the planned changes," the Red Sox said.
Cincinnati and Houston said their ballparks already are in compliance.
MLB said it will work with teams and ticket sellers to identify which seats are behind netting. By 2017, the actual tickets are likely to indicate whether they are behind protection.
"We will fight to make these new safety measures more than just recommendations and to make sure the measures are adequate," said Steve Berman, a lawyer for several fans who in July sued MLB in U.S. District Court in San Francisco. "By next season, we don't want any spectators to be under the threat of being harmed by a foul ball or bat injury, period."
Pat O'Conner, president of the National Association of Professional Baseball Leagues, said the minor league governing body will "encourage our clubs to implement these recommendations as soon as practical."