(a) If a firefighter receiving pension payments reenters active service, pension payments shall be suspended while he or she is in service. If the firefighter again retires or is discharged, his or her monthly pension shall be resumed in the same amount as was paid upon first retirement or discharge unless he or she remained in active service 3 or more years after re-entry in which case the monthly pension shall be based on the salary attached to the firefighter’s rank at the date of last retirement.
     (b) If a deferred pensioner re-enters active service, and again retires or is discharged from the fire service, his or her pension shall be based on the salary attached to the rank held in the fire service at the date of earlier retirement, unless the firefighter remains in active service for 3 or more years after re-entry, in which case the monthly pension shall be based on the salary attached to the firefighter’s rank at the date of last retirement.
     (c) If a pensioner or deferred pensioner re-enters or is recalled to active service and is thereafter injured, and the injury is not related to an injury for which he or she was previously receiving a disability pension, the 3-year service requirement shall not apply in order for the firefighter to qualify for the increased pension based on the rate of pay at the time of the new injury.