Guide to NFL's new rules: What to know about approved, tabled and rejected proposals

Schefter: NFL rule change 'designed to have dramatic effects' (2:14)

Adam Schefter breaks down the NFL's new rule banning players from lowering their helmets during hits. (2:14)

ORLANDO, Fla. -- You know that NFL owners had an eventful annual meeting when a substantive change to the catch rule isn't the biggest headline of the week.

A data- and research-filled presentation from the NFL's medical staff on Tuesday prompted owners to demand a new and potentially far-reaching rule to ban players from lowering their heads to initiate contact with their helmets. Competition committee chairman Rich McKay scrambled to incorporate an intended point of emphasis into the rule book within hours, with plenty of details left to be determined.

As owners disperse Wednesday, let's review what we know about that rule and the other prominent on-field changes that were approved, tabled and rejected this week in Orlando.

New rule: 15-yard penalty for lowering head to initiate, make contact with helmet

What it means: For the moment, the biggest takeaway is mass confusion and angst. An unexpected, hurried and partial rollout has left many unanswered questions about a rule that McKay said was intended to change behavior of players at all levels of football. Here's what we know: It is now a foul when a player lowers his head to "initiate and make contact" with his helmet against an opponent. It will cost 15 yards and could -- as with the NCAA's targeting rule -- lead to ejection. What remains to be decided by the NFL's May 21-23 meetings: Would ejections be mandatory, or based on severity of the hit? Would those ejections be subject to replay? And how strictly will officials enforce the rule? Players lower their heads to initiate contact, with varying levels of contact, all the time. Stay tuned.

New rule: Revised standard for a catch

What it means: The requirement to "survive the ground" has been eliminated -- a change designed specifically to avoid future instances of counterintuitive rulings that spurred debate about plays involving Detroit Lions receiver Calvin Johnson in 2010, Dallas Cowboys receiver Dez Bryant in 2014 and Pittsburgh Steelers receiver Jesse James in 2017. Now, a receiver must control the ball, establish himself in bounds and perform a football move -- such as a third step or a lunge -- to make a legal catch. This definition applies to players who remain standing or are going to the ground. It will remain eligible for replay review. McKay believes this change makes the rule objective, but others -- including former officiating chief Dean Blandino -- think it will simply swap one set of debates out for another. Most notably: Did the receiver in fact perform a football move?

New rule: Permission for command center to eject players

What it means: Senior vice president of officiating Al Riveron can now order the ejection of a player who has been penalized for a non-football act such as punching or fighting. Referees retain the authority to eject as well, but there have been a handful of occasions in which league officials would have preferred an ejection, but had no option for overruling or assisting a referee with that decision. Two examples from 2017 include New England Patriots tight end Rob Gronkowski's late hit to the head of Buffalo Bills cornerback Tre'Davious White, and Tampa Bay Buccaneers receiver Mike Evans' blindside hit on New Orleans Saints cornerback Marshon Lattimore. Neither Gronkowski nor Evans was ejected by on-field officials, though both were later suspended for one game. In the future, Riveron will have the option to step in and demand an ejection via his wireless microphone connection with referees.

New rule: Permanent touchback at 25-yard line for kickoffs

What it means: This rule is no longer in the experimental phase, as it was in 2016 and '17. The goal was to make the kickoff safer by reducing returns. The league hoped that returners would be incentivized to settle for a touchback, given the field position, rather than run it out of the end zone. The return rate did drop to 40 percent over the past two seasons (from 41.1 percent in 2015), the touchback rate rose to 57.1 percent (from 56 percent in 2015) and fear of mass "pooch" kicks did not materialize. But injury rates remain high, according to Green Bay Packers president Mark Murphy. In fact, concussions remain five times as likely to happen on kickoffs than on the average play, and the league's competition committee will consider elimination of it altogether if that number doesn't decrease soon.

New rule: No PATs at end of regulation

What it means: Teams will no longer be required to kick a meaningless extra point, or kneel down, after a score on the final play of regulation. This situation arose in the divisional round of the 2017 playoffs, after the Minnesota Vikings' game-ending 61-yard touchdown play against the New Orleans Saints. The play put the Vikings ahead with no time remaining, setting off a wild celebration, but both teams had to reassemble for the PAT. That will no longer be necessary.

Tabled rule: Hiring head coaches who are in the playoffs

What it means: NFL teams still can't formalize a head-coaching hire until that coach's current team has played its final game. The competition committee had proposed an amendment that would allow the coach to sign a contract with the hiring team but not begin his new duties until after his current team's season is over. This would have prevented episodes such as the one the Indianapolis Colts experienced with Patriots offensive coordinator Josh McDaniels, who verbally agreed to terms in January but then reversed course after Super Bowl LII. The Colts had no recourse because McDaniels had not signed a contract. Teams that opposed the rule change argued that coaches could be distracted from their postseason duties, despite the required delay in starting their next job.

Tabled rule: Video on sidelines

What it means: Incredibly, in the year 2018, the NFL will continue to ban the use of video by coaches and players during games. They will continue to use still photographs instead, either printed or viewed on their Microsoft Surface tablets. But many coaches adamantly opposed the addition of All-22 video to the tablets. Why? They believe video would make it easier for ill-prepared or lesser-skilled teams and coaches to make in-game adjustments. While not defeated, the rule is unlikely to be put to a vote before the 2018 season, McKay said.

Withdrawn rule: 15-yard penalty for pass interference

What it means: Pass interference will remain a spot foul. The New York Jets had proposed a rule to change it to 15 yards, regardless of where it occurs on the field. This idea has been proposed before, but it gathered more momentum than in years past. Among those who supported it was New York Giants co-owner John Mara. Of the 303 such penalties last season, 129 were walked off more than 15 yards. But the Jets withdrew it before a vote, knowing it would not pass. Concerns remain about the incentive for defensive backs to commit intentional fouls beyond 15 yards to prevent big plays. The proposal made exceptions for "intentional and egregious" contact, but that distinction is considered too subjective for officials to make on a consistent basis.