Any firefighter who has completed his or her probationary period and has been permanently appointed, and sustains a disability not in the performance of his or her duty which renders him or her unable to continue his or her service, may request to be retired by filing a written request with his or her retirement board within sixty days from the date of his or her disability. The board may, upon such request being filed, consult such medical advice as it deems fit and proper. If the board finds the firefighter capable of performing his or her duties, it may refuse to recommend retirement and order the firefighter back to duty. If no request for retirement has been received after the expiration of sixty days from the date of his or her disability, the board may recommend retirement of the firefighter. The board shall give the firefighter a thirty-day written notice of its recommendation, and he or she shall be retired upon expiration of said notice. Upon retirement he or she shall receive a pension equal to fifty percent of his or her basic salary. For a period of ninety days following such disability the firefighter shall receive an allowance from the fund equal to his or her basic salary. He or she shall during said ninety days be provided with such medical, hospital, and nursing care as the board deems proper. No funds shall be expended for such disability if the board determines that the firefighter was gainfully employed or engaged for compensation in other than fire department duty when the disability occurred, or if such disability was the result of dissipation or abuse. Whenever any firefighter shall die as a result of a disability sustained not in the line of duty, his widow or her widower shall receive a monthly pension equal to one-third of his or her basic salary; if such widow or widower has dependent upon her or him for support a child or children of such deceased firefighter, he or she shall receive an additional pension as follows: One child, one-eighth of the deceased's basic salary; two children, one-seventh; three or more children, one-sixth. If there be no widow or widower, monthly payments equal to one-third of the deceased firefighter's basic salary shall be made to his or her child or children. The widow or widower may elect at any time in writing to receive a cash settlement, and if the board after hearing finds it financially beneficial to the pension fund, he or she may receive the sum of five thousand dollars cash in lieu of all future monthly pension payments, and other benefits, including benefits to any child and/or children.