NFHS Bat Rules

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2007-2020 NFHS Rules Revisions
NCAA BBCOR Testing Protocol / What is BBCOR?

July 6, 2011 - Prior to the June 2012 meeting of the Baseball Rules Committee, the NFHS will work with appropriate parties to research and develop a baseball bat tamper-evident protocol for non-wood bats and present the recommendations to the committee for its consideration. The goal for implementation is for non-wood bats manufactured after January 1, 2015.

 “Bat tampering is illegal and a major problem in high schools,” Hopkins said. “Everyone is looking for a competitive edge. With this note, we want to make sure that the state associations, coaches, teams and the public are aware that we are committed to minimizing any risk for players with bat tampering.”

In addition, a minor change to Rule 1-3-5 states that “No artificial or intentional means shall be used to control the temperature of the bat,” based on scientific research that altering the bat damages the bat and poses an unnecessary risk of injury.

Baseball Rules Change Puts Moratorium on Composite Bats

NFHS 2011 Composite Bat Lists are no longer needed. All bats must be BBCOR certified and stamped.
The two exceptions which are stamped are the
Reebok Vector-TLS bat, 33 inch only and the Marucci CAT5 33-inch model, which have both been decertified.
See a photo of the Marrucci CAT5.

INDIANAPOLIS, IN (July 7, 2010) — One of six new rules changes by the National Federation of State High School Associations (NFHS) Baseball Rules Committee forbids the use of composite bats until they can meet the Batted Ball Coefficient of Restitution (BBCOR) performance standard. The changes, which were subsequently approved by the NFHS Board of Directors, will take effect with the 2010-11 school year.

After thorough testing by the Baseball Research Center at the University of Massachusetts–Lowell, the NFHS Baseball Rules Committee voted to outlaw composite bats until they can produce consistent results through the life of the bat, be made tamper-evident and be labeled as a composite product.

Elliot Hopkins, NFHS liaison to the Baseball Rules Committee, visited with James Sherwood, director of the Baseball Research Center, and spent several hours witnessing composite bat testing. “Rolling the bat gives it a higher performance,” Hopkins said. “It can significantly increase the performance and that’s huge in our game.”

Rolling the bat isn’t the only problem. Rolling only speeds up the performance enhancement that would occur over time after normal use. Even composite bats that were not altered will eventually see this increase in performance, and the rules committee views that as a major concern.

Rule 1-3-2 through 5 was completely rewritten with the intention of creating a rule that preserves the intent and spirit of the old rule, but is better suited to products resulting from new technology.

Under the new rule, bats with composite handles and tapers would still be legal. The stricter language applies primarily to the barrel of the bat.

“While the handles and taper are important components of the bat,” Hopkins said, “the area that we recognized as more susceptible to abuse is the barrel.”

Other rules changes this year aim at increasing convenience for coaches and umpires by simplifying the substitution policy and clarifying several rules.

Rule 1-1-2 now requires coaches to list all known substitutes on the lineup card before the umpire accepts it. Coaches will still be able to add a substitute without a penalty, but this should speed up substitutions and player changes during the game.

A change to Rule 2-16-2 was also made to clarify an existing rule and ease its application for coaches and players. The rule now reads: “A foul tip is a batted ball that goes directly to the catcher’s hands and is legally caught by the catcher. It is a strike and the ball is in play.”

Similarly, a “last-time-by” rule has been instituted. The new rule states that if a runner correctly touches a base that was missed the last time he was by the base, that last touch corrects any previous base-running infraction. This last-time-by practice is commonly accepted, but is now legally Rule 8-2-6l.

The last two rules changes were approved on recommendation from the NFHS Sports Medicine Advisory Committee. First, in a change to Rule 1-5-8, all hard and unyielding items such as braces, casts, etc., must be padded with a closed-cell, slow-recovery foam padding no less than one-half-inch thick. Knee and ankle braces that are unaltered from the manufacturer’s original design/production do not require additional padding.

Second is an update to concussion language that has been added to the rules for all high school sports. The new rule, 3-1-5, puts strict constraints on players who may have suffered a concussion. The rule states that any player who exhibits signs, symptoms or behaviors consistent with a concussion, including but not limited to loss of consciousness, headache, dizziness, confusion of balance problems, must be removed from the contest immediately and shall not return to play before being cleared by an appropriate health-care professional.

A complete listing of all rules changes approved by the committee is available on the NFHS Web site at Click on “Athletics & Fine Arts Activities” on the home page, and select “Baseball.”

Baseball is the fourth-most popular sport for boys at the high school level, according to the 2008-09 NFHS Athletics Participation Survey, with 473,184 participants nationwide. The sport ranks third in school sponsorship with 15,699 schools sponsoring the sport.

2010 Baseball Rules Changes Include Bat Standards Adjustment

INDIANAPOLIS, IN (July 6, 2009) — The clarification of baseball bat specifications was among four rules adjusted by the National Federation of State High School Associations (NFHS) Baseball Rules Committee at its annual meeting June 7-9 in Indianapolis. The rules changes subsequently were approved by the NFHS Board of Directors.

A change to Rule 1-3-2 regarding bat specifications was made in the hope it will clarify bat compliance. The rule, which will be effective January 1, 2012, specifies that the bat should be a “smooth cylinder implement from the top of the cap to the top of the knob.”

“The committee was looking to clarify the rule and make the purchase of bats an easier process,” said Elliot Hopkins, NFHS director of educational services and liaison to the Baseball Rules Committee. “We want to make sure that kids and parents know what is permissible.”

The change will also require that all non-wood bats meet the Batted Ball Coefficient of Restitution (BBCOR) performance standard, which is the standard used by the National Collegiate Athletic Association (NCAA). Formerly, non-wood bats had to meet the Ball Exit Speed Ratio (BESR) standard.

The new rule also states that non-wood bats must be labeled with a rectangular certification mark “a minimum of a half-inch on each side and located on the barrel of the bat in any contrasting color.” The new standard ensures that performances by non-wood bats are more comparable to those of wood bats. It’s also expected to minimize risk, improve play and increase teaching opportunities.

“After working with the NCAA and having access to its research, we’ve concluded it’s in our best interest to make this change,” Hopkins said. “BBCOR includes the BESR standard, so we’re actually expanding upon our current standard, which will be more appropriate for our age and skill level.”

Another major rule addition applies to assistant coaches and their behavior during the game. Rule 3-3-1g6 prohibits any member of the coaching staff who is not the head coach from leaving “the vicinity of the dugout or coaching box to dispute a judgment call by an umpire.” The penalty for this infraction is that both the head coach and the offending coach will be restricted to the dugout for the remainder of the game. If severe enough, the umpire also has the authority to eject the offending coach and/or the head coach.

The intention of this change is to cut down on the disruptive and counterproductive behavior of assistant coaches. It also reinforces to head coaches that they are responsible for their staff and players.

“The committee found that assistant coaches were taking license with their roles and becoming disruptive,” Hopkins said. “By doing that, they’re sending the wrong message to their players. It’s one thing to ask the official for a clarification, but it’s another to challenge and charge an umpire. We cannot and will not allow that.”

A clarification was made to Rule 1-2-4 concerning the temporary extension of dugouts. The modified rule explains that when the dugout is to be temporarily extended, it shall be extended toward the outfield and not toward home plate.

The final adjustment was made to Rule 7-4-1f, concerning the instances when a batter will be declared out. The change reads that the batter is out if “any member of the offensive team or coach other than the runner interferes with a fielder who is attempting to field a foul fly ball.” The addition of the phrase “other than the runner” clarifies the responsibility of the runner and that the runner — not the batter — will be declared out for the runner’s interference.

“Previously, it just wasn’t fair to the batter,” Hopkins explained. “If the runner interferes with the defense, it’s not the batter’s fault. It was the runner who created the infraction, so the runner will be called out.”

Bats with BESR Standard Legal Immediately in HS Baseball

INDIANAPOLIS, IN (March 22, 2002) — Effective immediately, any bat that meets the Ball Exit Speed Ratio (BESR) performance standard (BESR certification mark on the bat) is legal for high school baseball competition governed by National Federation of State High School Associations (NFHS) rules.

In June 2001, the NFHS Baseball Rules Committee voted that all non-wood bats must have the BESR certification mark to be legal for high school baseball, effective January 1, 2003. Since many bats with the BESR standard are already on the market, this interpretation by the NFHS allows those bats to be used in the 2002 high school season.

“When purchasing bats, individuals can now be assured that no matter what materials are used in the bat composition, if it has the BESR certification mark, it is legal,” said Elliot Hopkins, NFHS assistant director and liaison to the Baseball Rules Committee. “Whether the bat composition is titanium, ceramic or whatever, if it has the BESR mark, it can be used immediately.”

Hopkins said that bats with the BESR mark still are not required until January 1, 2003. Bats that are legal by current rules still can be used for the 2002 season; however, all bats must have the BESR mark for the 2003 season.

The BESR mark ensures a maximum exit speed of 97 miles per hour and that the bat has met the moment-of-inertia requirement. In addition, bat rules that were changed for the 2001 season, which are also a part of the BESR standard, have the following requirements: maximum of 2 5/8 inches for the diameter of the bat barrel and a minus-3 differential between the length and weight of the bat (a 33-inch-long bat, for example, cannot weigh less than 30 ounces).

All recent changes in bat requirements have been to minimize the risk of injury to high school student-athletes, and maintain the balance between offense and defense and keep within the sound traditions of the game.

NFHS Board of Directors Approves New Bat Rule

Kansas City, MO (January 7, 2000) — The National Federation of State High School Associations (NFHS) will have a new bat rule for the 2001 high school baseball season.

At a meeting in San Francisco, the NFHS Board of Directors approved a rule calling for narrower, heavier and more wood-like bats. The maximum diameter of bats will be reduced from 2¾ inches to 2 5/8 inches, and the unit differential, namely the difference between bat length measured in inches and bat weight measured in ounces, will be reduced from five units to three units.

The Board commended the work of the NFHS Baseball Rules Committee, but chose to defer action on two other bat-related committee proposals. One deferred proposal would have imposed a more restrictive maximum exit ball speed than the one recently adopted by the NCAA. The other would have imposed a wood-like moment-of-inertia requirement. The Board expressed interest in both proposals, but decided to return them to the rules committee for further assessment.

In addition to the new size and weight limitations, the NFHS Board of Directors anticipates that bats used in play after January 1, 2001, will comply with the new NCAA exit ball speed rule. In fact, the presence of a mark denoting compliance with the NCAA bat rule will be one assurance that a bat is compliant with the size and weight components of the new NFHS rule. Although bats meeting the new NFHS rule will not be required for another year, they are legal immediately. Student-athletes, parents and coaches wishing to utilize such bats this year are free to do so.

"The game of high school baseball is in good shape," said NFHS President Dick Durost. "Even so, we need to stay vigilant to ways in which technology is having an impact. The new rule will make the physical dimensions of non-wood bats more closely mirror those of wood bats. Further changes relating to bat weight distribution and exit ball speed may soon be in the offing."

The NFHS is the national service and administrative organization for high school athletics and fine arts programs in speech, music, drama and debate. Its membership consists of the state high school athletic and activity associations in all 50 states plus the District of Columbia.

The NFHS promulgates voluntary playing rules in 17 sports for girls and boys competition. When considering a rules change, the NFHS looks at risk minimization, the balance between offense and defense, and the sound tradition of the sport in question.

Baseball Rules Committee

Recommendation for a Bat Rule Change
The Baseball Rules Committee assesses potential rules changes in the light of three factors:

Risk minimization; Maintenance of an appropriate balance between offense and defense; and preservation of the sound traditions of the sport of baseball.

For the last two years, the Committee has publicly expressed an intention to change the bat rule so as to make the maximum permissible performance for bats used in interscholastic competition more akin to wooden bat performance. The reasons for the Committee’s statement of intention have been several-fold, including the following: Although generally accepted scientific data quantifying bat performance has until recently not been available, premium non-wood bats appear to be performing at increasingly high levels. The Committee draws its conclusion from the personal observations of its members, from news reports and anecdotal data (e.g., College World Series offensive statistics), from empirical data and from manufacturers’ own promotional literature.

Student-athletes and their parents have always understood, or always should have understood, that there are risks inherent in the sport of baseball. Every year, some high school baseball players will be seriously injured or perhaps killed. That being said, the level of risk historically understood to be associated with batted balls stems from the use of wooden bats and earlier generations of non-wood bats. Common sense tells us that such risk is increased in some measure when balls come off premium non-wood bats at greater exit speeds.

Higher exit ball speeds indisputably lead to a change in the balance between offense and defense, not just in the effectiveness of the offense, but also in the way the defense aligns itself.

Bat manufacturers are very good at their jobs. They are producing bats that, on the basis of their own literature, continue to perform more effectively. Some technological improvements have enhanced durability, and some have improved performance. There is no basis known to the Committee on which it could conclude that technological innovation has reached its end point.

The Committee believes that the time has come to convert its twice-stated intention into a specific rule. Advances in the science of bat testing have made the Committee more comfortable about recommending action at this time. There remain two central questions the NFHS must answer:

  1. What should the new rule be?
  2. On what time-table should the new rule go into effect?

The New Rule:

We recommend that the NFHS Board of Directors approve a rule for non-wood bats that in size, weight and moment of inertia, replicates wood. Specifically, the rule would require that non-wood bats have a 2 5/8" maximum barrel diameter, a minus 3 unit maximum differential (measured without the grip) and a minimum moment of inertia (MOI) of 9000 oz-in2 measured at the 6" point from the knob. Such a weight and moment of inertia would cause the effort required to swing a non-wood bat to replicate closely the effort required to swing a wooden bat. (We intend to adopt a maximum exit ball speed, but we believe that now would be a premature time to do so. We expect that such a rule would be considered for adoption next summer, with a target implementation date of January, 2002.) We do not want to act in a way that imposes undue hardship on any of the affected parties - student-athletes, parents, high schools, dealers and manufacturers. Rules are exact, but the rule-making process often cannot be. We must do the best job we can in the midst of well-meaning but often conflicting interests and beliefs. At this time, the changes described herein seem to us to be appropriate for play at the high school level.


With respect to implementation, we are guided by the premise that the greater the safety risk posed by a given product or procedure, the greater the economic dislocation appropriate when fashioning a remedy. Bats pose some safety risks to student-athletes, coaches, umpires and spectators. The abrupt disallowance of certain previously permissible bats would cause some hardship to student-athletes, parents, high schools, dealers and manufacturers.

The Committee is aware that student-athletes have suffered bat-related injuries in 1999 and in previous years. However, the committee is not aware of a material change in the rate of such injuries.*

Nor does the Committee believe that the rate of such injuries has yet become materially greater than it would be if wooden bats were in general use. The change proposed by the Committee may be viewed, in part, as precautionary against a future uptrend in injuries.

The sources of the Committee’s knowledge about injuries include the following: The report to the Committee by Professor Frederick Mueller of the University of North Carolina. The membership surveys conducted by the NFHS in 1998 and 1999. The injury statistics assembled by the NCAA.Each Committee member’s personal experience, anecdotal data, and information from his review of news reports and other relevant materials. The rule change suggested by the Committee is a lowering of the ceiling of permissible bat performance. Non-wood bats meeting the new three-part criteria set forth herein have always been permissible, and student-athletes and high schools are free to utilize them immediately. With respect to that segment of currently permissible bats that would no longer be permissible (referred to hereafter as "1998-99 Dimension Bats"), we recommend a two-year phase out period. During the first year (the 2000 season), 1998-99 Dimension Bats, whenever purchased, could be used. During the second year (the 2001 season), 1998-99 Dimension Bats that were purchased prior to the end of the 1999-2000 academic year could be used. From the 2002 season onwards, 1998-99 Dimension Bats would no longer be permissible. * Any serious injury or death is cause for sadness and concern. However, to do away with all risk of injury or death would be to do away with the sport of baseball as we have known it in this nation for a century and a half. The question has to be, what is the level of risk that student-athletes (and their parents) should have to accept in order to play high school baseball?

Proposed Bat Testing Protocol

The NFHS has just received the following proposed bat testing protocol from Dr. James Sherwood in follow-up from the December 5, 1999 meeting of the NFHS Baseball Rules Committee. In the interest of expedition, the NFHS is posting the proposed protocol at this time, and requesting comments by scientists, manufacturers and others at their earliest convenience.  

National Federation of High Schools
Proposed Standard for Testing Baseball Bat Performance
Certification Protocol

December 21, 1999
Initial Written Notification
To initiate the certification process for all baseball bats that are constructed with materials other than one-piece solid white ash, an interested bat manufacturer must send the NFHS written notice of its intent to conduct certification testing on specific models it deems appropriate for testing. The notice to conduct testing must contain a detailed description of all models to be used in NFHS competition, the date of first production, the model number, the bat length and weight combination of each model to be manufactured, the maximum diameter, the handle diameter, location of the center of gravity (balance point as measured from the tip of the barrel), the nominal wall thickness of the barrel and of any other part of the bat with a wall thickness that differs from the barrel, the ultrasonic setting used to determine wall thickness, and the materials (e.g., alloys, composites, any filling or deadening materials) used to make the product (including, without limitation, any materials used inside the bat and the materials composing and/or contained in the bat’s end cap). Such information shall not be confidential, and shall be available on request. In addition, an 8" x 10" color photograph of each model to be certified shall be provided to the NFHS. At that time, the NFHS will provide the manufacturer with a testing reference number, e.g. NFHS-2000-0001, in writing, and only those bat models will be cleared for testing.

Certification Process
The NFHS then will require that a manufacturer supply a minimum of two typical bats of every length class (per Table 1), weight class (per Table 2), and model combination for certification to James A. Sherwood, University of Massachusetts at Lowell, James B. Francis College of Engineering, Department of Mechanical Engineering, One University Avenue, Lowell, Massachusetts 01854 (978/934-3313, A purchase order to the "University of Massachusetts at Lowell – Research Foundation" should accompany the bats.

Dr. Sherwood and his research team will conduct the certification tests as stated in the testing protocol on one of the bats for each length, weight and model combination. All bats of each particular combination which are sold or otherwise provided for NFHS play by the manufacturer must meet the specifications of the new standard in order for that combination to be certified for NFHS competition. If approved, the NFHS will provide written confirmation for each approved combination bat and will issue a certification number for each approved combination bat.

Table 1. Length classes for bats

Length Class (In.)

30.0 -0.25/+0.24

30.5 -0.25/+0.24

31.0 -0.25/+0.24

31.5 -0.25/+0.24

32.0 -0.25/+0.24

32.5 -0.25/+0.24

33.0 -0.25/+0.24

33.5 -0.25/+0.24

34.0 -0.25/+0.24

34.5 -0.25/+0.24

35.0 -0.25/+0.24

35.5 -0.25/+0.24

36.0 -0.25/+0.24

Table 2. Weight classes for bats without grip

Weight Class
(Unit difference, weight from length)
-3.00 to -2.50
-2.49 to -1.50
-1.49 to -0.50
-0.49 to +0.50

A mandatory silk-screen or other permanent certification mark shall consist of the phrase "NFHS Certified" and must be clearly displayed on the barrel end of the bat. The manufacturer may use the certification mark in descriptive materials (such as catalogs) to identify bats that comply with this testing standard, but may make no other use of the mark. Use of the certification mark to advertise or promote the sale or distribution of bats is expressly prohibited.

In the event that all bats submitted for testing become damaged and unusable for testing, the manufacturer will be notified by the Certification Center via e-mail and requested to submit at least two more bats for certification. The certification of that length, weight and model combination will then go to the next open position in the certification queue, i.e. end of the line, upon receipt of the new bats.

All bats will be returned except for the tested bat(s) and one untested bat for record purposes. The retained bats will be stored in a secure area and only Certification Center personnel will have access to the secure area. The manufacturer will be assured that the confidentiality of its bat is protected.

Test Results
Dr. Sherwood will simultaneously provide the NFHS and the manufacturer in writing with the test results of each length and weight combination for each model submitted by the manufacturer for certification. If a bat is submitted for testing by a sponsor other than the manufacturer, Dr. Sherwood will provide the test results in writing to the NFHS and the sponsoring party. If a bat submitted by a sponsor other than the manufacturer fails the certification test, copies of the test results will also be provided in writing to the manufacturer.

Copies of all confidential data sheets will be supplied to the NFHS and to the test sponsor for every hit. If a bat that has been submitted for testing by a sponsor other than the manufacturer fails the certification test, copies of all confidential data sheets will also be supplied to the manufacturer. The original data sheets will be filed in hard copy and digital form at the Certification Center and in digital form at a secure off-site location. Information on the data sheet belongs to each test sponsor (and the manufacturer, if the test sponsor is not the manufacturer and the bat fails the certification test), for internal purposes only and shall be kept confidential by the certification center and the NFHS unless otherwise provided herein. The NFHS will retain the right to announce publicly that a bat has failed the certification test.

Manufacturers may not disclose the BHM test data. If a manufacturer discloses such information, the NFHS may make any additional disclosure of information from the same test that it deems appropriate.

Testing Expenses
All of the expenses to conduct the testing at the University of Massachusetts at Lowell Baseball Research Center will be funded by the manufacturer or test sponsor for which certification testing will be conducted. All manufacturers should interface directly with Dr. Sherwood regarding the testing expenses.

Implementation Timeline

Beginning January 1, 2001, only baseball bats that display an official NFHS certification mark on the barrel-end of the bat signifying compliance with the NFHS's bat performance standard will be allowed in regular-season and post-season competition. Solid white ash bats will be allowed for NFHS competition.

Compliance with the Performance Standard

The NFHS will conduct discretionary periodic testing of certified baseball bats. This testing is intended to sample fairly the bats used in NFHS play at the time of the testing. Bats will be obtained from both dealer stock and field service. If any nonconforming bats are identified, the NFHS will notify the manufacturer in writing of its findings. A bat length, weight and model combination will not be declared nonconforming unless three different bats with that length, weight and model combination have failed the certification test. The manufacturer will be given the opportunity to review the compliance report and will be allowed an appeal in writing of the findings to the NFHS Rules Review Committee within fourteen (14) days upon receipt of the notice of findings. This right to appeal shall include a right to retest the bat or bats in question at the manufacturer’s expense, and the results of any retest shall be simultaneously provided to the manufacturer and the NFHS. Once any retesting is complete, the Rules Review Committee will act on the appeal and will notify the manufacturer of its decision within seven (7) days. The Rules Review Committee shall disallow any bat for regular-season or post-season competition that does not meet the standard. A manufacturer may, within seven (7) days of such notification, appeal a decision of the rules Review Committee to the NFHS Board of Directors.

Manufacturer Right to Submit a Competitor's Bat for Compliance

Manufacturer A is permitted to submit Manufacturer B's bat for testing and A pays for the testing regardless of outcome. If B's bat does not comply, then the Certification Center will notify the NFHS and the NFHS will take appropriate steps for noncompliance as described above. The same appeal procedures as described above shall apply in this circumstance, and the test sponsor shall be entitled to the results of any retest and appeal. The results of the test (including all test data) will be shared with the NFHS and the test sponsor in the manner described above. If the bat fails the certification test, the test results will also be shared with the manufacturer.

Penalty for Modification of Bat after it leaves the OEM

A manufacturer will not be held responsible for noncompliance in the event that an aftermarket party alters the bat in any manner. The NFHS will deal directly with the team that collaborated with the aftermarket party. The manufacturer should make a best effort to produce a tamperproof bat, e.g. no screw-on end cap.

Testing Protocol

Bat Preparation Procedures
1. Measure and record model, length, weight and location of balance point.
2. Draw impact lines and axis line.
3. Measure and record diameter at 3", 4", 5", 6", 7", 8" and 9" from the tip of the barrel and 8" from the base of the knob.
4. Drill safety-pin hole(s) at 1-7/16" from the base of the knob. Bats that can only be hit label-up or label-down will have one hole.
Bats that can be hit anywhere around the circumference will have two holes (90° apart)

Mounting in the BHM

Mount in grip, lock with safety pin 1-7/16" from base of the knob such that the rotation axis is 5-7/16" from the base of the knob, and align axis of bat with ball center. The grip material will be Astroturf and/or rubber. The grip material(s) will be uniform from test to test, and no set of grip material(s) will be used for more than 8 hours of continuous testing. The grip material(s) will be allowed to relax for a minimum of 8 hours before being reused.

Bat-Swing and Ball Pitch Speeds

Input target speeds as specified in Table 3 for the bat swing speed as a function of bat length (velocity measured at a point 6 inches from the barrel end) and 70+2 mph ball pitch speed to yield a combined speed as specified in Table 3. The tolerance on individual input speeds is to allow for test variance on a dynamic hitting machine (Baum Hitting Machine).

Torque Cutoff to Coast
The torque supplied to the bat by the servo is cutoff 12.8 inches prior to impact. This torque cutoff ensures that the bat is coasting through the bat/ball collision as opposed to being powered through the collision. Because the bat speed may vary from test to test, the coast time will likewise vary from test to test, but the coast distance is fixed to be 12.8 in.

Determination of a Valid Hit
For a reading to be valid, ball exit speed as measured at the 72" speed-gate location must be less than the higher of the speeds as measured at the 9" and 13" light-cell positions. The pitch speed must be within +2 mph and the swing speed must be within +0.5 mph of their respectively prescribed values. The combined speed must be within +2.5 mph of its prescribed value.

The bat speed on the datasheet is measured at the impact location. This impact location is not always at the 6-inch position on the bat. Therefore, the swing speed to conclude whether or not the hit was valid needs to reflect the appropriate speed at the point of contact for a swing speed of Vset mph at the 6-inch location. Where Vset is the prescribed swing speed as denoted in Table 3 for the bat length being tested. Equation (1) calculates the ideal swing speed at the point of contact:

Equation1.jpg (4217 bytes)

Where Vset is bat speed at the 6-inch location, Vcontact is the bat speed as recorded on the test datasheet, Length is the overall length of the bat, and Location is the hit location, e.g. 6.5-inch, or 7.0 inch, etc. A valid swing speed must be within Vcontact +0.5.

The BHM measures the bat swing speed at the point of contact, and this swing speed is written on the test datasheet. The measured bat input speed can be adjusted accordingly to reflect the bat input speed at the 6" point by use of Equation (2):

Equation2.jpg (4005 bytes)

Where V is bat entry speed at the 6-inch location, Vcontactis the bat entry speed as recorded on the test datasheet, Length is the overall length of the bat, and Location is the hit location, e.g. 6.5 in. or 7.0 in.

The ball must pass through the exit hole and not be too far left or right or high or low. The target is 62-1/16 in. from the impact point. The target is a diamond with equal diagonals of 13-in, i.e. a square, as shown in Fig. 1. One diagonal is horizontal and parallel to the bat axis. Three strings hang in the target for judging ball position manually. One string hangs from the top center of the diamond and extends to the horizontal diagonal. Parallel strings hang +2 in. on either side of the centerline string. If a ball hits the left string, then it is described as being "too far left". If a ball hits the right string, then it is described to be "too far right". If the center of the ball is judged by the test operator to be >2 in. below the horizontal centerline of the target, then it is described as "too low". If the center of the ball is judged by the test operator to be >2 in. above the horizontal centerline of the target, then it is described as "too high".

BHM Target Window

Fig. 1 BHM Target Window

Exit-Velocity Readings and Impact Location
All bat positions are measured with respect to the distance from the tip of the barrel. Raw data exit velocities are to be recorded with testing commencing at the 6" point. Bat profiling will continue with hits at the 5", then the 7" points. If deemed necessary for certification purposes, bat profiling will continue at the discretion of the certification personnel with hits at additional points by using 1" and/or 0.5" and/or 0.25" increments. Five (5) consecutive valid exit-velocity readings are to be recorded at each of the bat-axis impact locations. Consecutive valid readings will be determined without regard to any interspersed invalid readings; thus, for example, three valid readings, followed by an invalid reading, followed by two valid readings will be considered five consecutive valid readings. The total number of hits may vary from bat to bat.

The wood bat standard and wood bat certifications will be based on at least three (3) valid hits at each impact location. Wood bat testing will commence with 3 impacts at the 6" point. Bat profiling will continue with 3 hits at the 5.5", then 3 hits at the 6.5" points. If deemed necessary for certification purposes, bat profiling will continue at the discretion of the certification personnel with hits at additional points by using 1" and/or 0.5" and/or 0.25" increments. Once the "sweet spot" is isolated, two (2) more impacts will be completed on that location.

The non-wood bats will be randomly rotated prior to each hit. The wood bats will be rotated 180 degrees prior to each hit according to standard wood bat usage, i.e. label up and label down. Alignment of the bat will be checked before each hit.

Work Hardening
The batted ball speed off some metal bats has been observed to increase as the bat is impacted repeatedly. To capture any potential increase in bat performance due to working the metal, the metal bats will be submitted to a second cycle of 5-hit impacts. For example, the first hit cycle for certification impacts will commence with 5 hits at the 6" location, then 5 at 5", then 5 at 7", then 5 at 5.5", and finally 5 at 6.5". The next cycle will start with 5 hits at the 6" location. If the 5-hit average for batted ball speed for the second cycle is greater than the 5-hit average for the first cycle, then the bat is suspected to be potentially work hardening and a complete second cycle of hits is completed. This cycling of certification hits continues until the certification personnel conclude the batted ball performance has stopped increasing.

Length-to-Weight Unit Differential

The length-to-weight unit differential of each non-wood bat shall not exceed three units without the grip. Each length-class and weight-class combination of a particular model must be certified for compliance.

Bat Surface

The surface of the bat tested for certification must be the same as that of the production bat model which it represents and may exclude graphics. Bat Diameter
The barrel diameter shall be no greater than 2.625 inches. A certified bat ring (no more than 1/4-inch thick) with an interior diameter of 2.635 inches must pass completely over the length of each bat prior to each hit. If the ring fails to pass over the entire length of the bat, then the bat is concluded to be illegal for NFHS competition.
Balance Point

There is no specification for the center of gravity, a.k.a. the balance point. However, the balance point will be recorded. MOI (Mass Moment of Inertia)
The MOI for all non-wood bats must be greater than the minimum value prescribed for that length group. Table 4 denotes the minimum MOI values for each length class.

Table 4. Minimum MOI values as a function of length
and as measured 6 inches in front of the knob

Length Class(in)

Minimum MOI























Baseball Specifications

The ball shall have a weight of 5.12+0.035 oz. The circumference of the ball shall be 9.05+0.05 in. The COR of the baseball must be 0.522+0.006.

In a lot of 144 baseballs, six (6) will be randomly selected and tested to ensure that ball COR falls within the specified range of 0.522+0.006. If any one ball fails to meet this COR standard, then the entire lot is concluded to be unusable for certification testing. The six (6) balls tested for COR will not be used for bat testing.

In a lot of 144 baseballs, six (6) will be randomly selected and tested to ensure that ball compression is no greater (within a reasonable range) than the compression characteristics of balls used in previous testing during November 1999. If any one ball fails to meet this compression standard, then the entire lot is concluded to be unusable for certification testing. The six (6) balls tested for compression will not be used for bat testing.

In a lot of 144 baseballs, 20 baseballs to be used for certification will be tested on the BHM and the exit velocity will be recorded. The balls will be hit on the logo panel with the 6-in. point of a 34/31 Baum AAA Pro bat with a 2.5" diameter and a mass moment of inertia greater than 680 lb-in2 at (70+2 mph pitch)+(68+1 mph swing speed @6" point)=138+3 mph. Baseballs for certification testing must fall within the acceptable exit velocity range (91+1.5 mph).

Ball Impacts
Each of the test baseballs used during certification tests will be impacted a maximum of eight times (two sets of impacts on four opposite panels). Hitting will commence with the logo panel.

Bat Preparation

Bats will be brought to laboratory environment temperature 72+3°F prior to testing. Wood-based bats will be will be stored at 72±3°F and 70±5% relative humidity for a minimum of 5 days prior to testing.

Baseball Preparation

Baseballs shall be stored in the laboratory environment for at least 24 hours prior to testing. Baseballs shall be stored in airtight containers. The balls shall be weighed again just prior to testing. Baseballs must meet the weight and circumference specifications in order to be used.

Laboratory Environment

The temperature in the testing lab shall be 72+3°F and a relative humidity of 50+5%.

Manufacturer Attendance

Manufacturer attendance is optional. Outside observers representing the organization that submitted the bat for testing may be present, but must follow the directions of the certification operators.

Pass-Fail Criteria
1. The bat must meet the MOI, size and weight specifications.
2. There are no tolerances for length-weight ratio (no greater than three units without the grip) or maximum barrel diameter.
3. The 2.635-in ID bat ring must pass over the entire length of the bat before and after every hit.
4. The ball-exit velocity must not exceed 95 mph.


The NFHS will revise the protocol as needed and reserves the right to change the test equipment, test location and the testing personnel. The NFHS will make every effort to make any future changes to the rule or protocol well in advance of any baseball season which would be affected by that change.

NFHS Rules Revisions

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