Subsistence allowance is part of wages for ESI purposes. Though this is an amount that an employee receives while he is not working (during suspension) this amount will attract ESI.
In the case of EPF, there is a different interpretation that subsistence allowance being a payment made to suspended employee for his survival and it is earned by him not on working the same should not be subjected to EPF contribution. Therefore, no PF deduction or contribution shall be made on subsistence allowance.