Form 1 NATIONAL RAILROAD ADJUSTMENT BOARD Award No. 28501
 THIRD DIVISION Docket No. SG-28907
 90-3-89-3-309
 The Third Division consisted of the regular members and in
 addition Referee Barry E. Simon when award was rendered.

 (Brotherhood of Railroad Signalmen PARTIES TO DISPUTE: (CSX Transportation, Inc.

STATEMENT OF CLAIM: "Claim on behalf of the General Committee of the Brother
 hood of Railroad Signalmen on the Baltimore and Ohio
 Railroad Company (B50):

 On behalf of H. L. Miles, for payment of 20 days pay at his pro-rata rate of pay, account of Carrier violated the current Signalmen's Agreement, as amended, particularly, the Discipline Rule, when it failed to meet its 'Burden of Proof.' Carrier file 15-50 (88-46)."

 FINDINGS:
The Third Division of the Adjustment Board upon the whole record and all the evidence, finds that:

 The carrier or carriers and the employe or employes involved in this dispute are respectively carrier and employes within the meaning of the Railway Labor Act as approved June 21, 1934.

 This Division of the Adjustment Board has jurisdiction.over the dispute involved herein.

Claimant was assessed a twenty (20) day suspension for failure to properly maintain a switch to FRA and Carrier standards, thereby causing a derailment. Following the derailment, three Carrier officials conducted an on-site inspection to determine the cause. They concluded that the switch point on a crossover switch was gapping, which caused the lead wheel of a tri-axle engine to go down the main track while the trailing two wheels went into the turnout. The gapping switch point was attributed to improper maintenance.

 While the Organization introduced the possibility of other causes for the derailment, it is not the function of this Board to second guess the Carrier when there is subst Form 1 Award No. 28501
 Page 2 Docket No. SG-28907
 90-3-89-3-309

 contacts in the circuit controller would not open until the switch was opened at least one-half inch, although FRA standards require the contacts to open when the point is open one-quarter inch or more. There is no basis to conclude that the Carrier was
Having found that the charge against Claimant was proven, we turn to the quantum of discipline assessed. The failure to maintain switches and signals is a serious offense which could have dire consequences. The record shows several instances where the Carrier has assessed thirty (30) day suspensions for similar viola Carrier noted that consideration was given to Claimant's 44 years of service without discipline. We conclude, therefore, that Claimant's exemplary prior record has already resulted in mitigation of the discipline and we are constrained from reducing it


        Claim denied.


                          NATIONAL RAILROAD ADJUSTMENT BOARD

                          By Order of Third Division


Attest: ,
      ' aJ1ever - Executive Secretary


Dated at Chicago, Illinois, this 7th day of August 1990.