A member may qualify for a disability pension under any one of the following mutually exclusive provisions:

(1) If a member receives total disability in line of duty, he shall be entitled during the time of his disability to a monthly disability pension equal to fifty percent of the monthly salary of the member at date of disability: Provided, That the minimum payment shall be $100 per month. Any benefits payable from the retirement and benefit fund shall be reduced by benefits payable from workers' compensation due to the total disability of the member.

(2) If a member receives total disability not in line of duty while an employee of the city after he has had at least ten years' total service credit and such member is not entitled to a retirement pension under the provisions of section seven of this article, he shall be entitled during the time of his disability to one half of the retirement pension to which he would have been entitled under the provisions of said section seven had he been sixty years of age at date of disability and had elected to take retirement: Provided, That he shall be entitled to a minimum payment of $50 per month and a maximum payment of $100 per month. Effective January 1, 1987, a city may provide that the maximum payment be $300 per month.

(3) If a member becomes so physically or mentally disabled as to render him unfit for the performance of the duties of the position he occupies, but his disability does not constitute either total disability in line of duty or total disability not in line of duty, and such member has less than ten years' total service credit, he shall be entitled to an annuity which shall be the actuarial equivalent of his total accumulation at the date of his disability.

The board of trustees of the fund shall order a periodic reexamination of members of the fund receiving a disability pension, and if the disability no longer exists the payment thereunder shall be discontinued: Provided, That no such reexamination of any such member shall be ordered as aforesaid after such member attains the age of sixty years.