what is safety salary

Vinay Raja (student-IPCC) (704 Points)

30 November 2010  

safety salary was allowed as deduction for computing income from PGBP in a problem of taxmann

i follow TN.Manoharan as reference book as my institute follows it, i never came across the word safety salary in TN.Manoharan.

can you please clarify me what actually safety salary is
 and under which section of IT Act it is an allowable expenditure