Standard Deduction for pensioners

deduction from salary [section 16]
the income chargeable Under the head " salary " shall be computed after making following deductions
(ia) a deduction of forty thousand rupees or the amount of salary, which ever is less
and other deductions under subsection (II) &(III)

so, the standard deduction is rs 40,000 or the amount of salary, which ever is less is deductible from gross salary