53 Pa. Stat. § 30564
At the time of his superannuation retirement, any beneficiary may elect to receive either his retirement allowance payable throughout life, or to receive the full amount of the accumulated deductions standing to his individual credit in the member's annuity reserve account at the time of his voluntary or involuntary retirement, or he may in any event elect to receive the actuarial equivalent of his member's and city annuity in a lesser retirement allowance payable throughout life with provision that--
Option One. If he dies before receiving in payments the present value of his member's annuity and city annuity as it was at the time of his retirement, the balance shall be paid to his legal representatives or to such person having an insurable interest in his life, as he shall nominate by written designation, duly acknowledged and filed with the board at the time of his retirement or at any time thereafter.
Option Two. Upon his death his member's annuity and city annuity shall be continued through the life of and paid to such person having an insurable interest in his life as he shall nominate by written designation duly acknowledged and filed with the retirement board at the time of his retirement.
Option Three. Upon his death one-half of his member's and city annuity shall be continued through the life of and paid to such person having an insurable interest in his life as he shall nominate by written designation duly acknowledged and filed with the board at the time of his retirement.
53 P.S. § 30564