Dear Vinayak ji,
You want to know procedure of 7A inquiry. To know the procedure, you should know what is 7A inquiry.
CPFC, ADCPFC, DYPFC, RPFC or APFC may order and may conduct such inquiry as he may deem necessary.
(a) in a case where a dispute arises regarding applicability of Act to an establishment, to decide such dispute; and
(b) determine the amount due from employer under any provision of Act&scheme, pension scheme and insurance scheme.
The officer conducting the inquiry has same power as are vested in a court under CPC 1908 for trying a suit in respect of following:
(a) enforcing attendance of any person or examining him on oath.
(b) requiring the discovery and production of documents,
(c) receiving evidence on affidavit.
(d) issuing commissions for examination of witnesses.
Any such inquiry is deemed to be a judicial proceeding within the meaning of Section 193 & 228 and for the purpose of Section 196 of IPC.
It is a Quasi-judicial proceeding.
No order is given unless the employer concern is given a reasonable opportunity of representing the case.
If employer fails to attend the inquiry without assigning any valid reason or fails to produce any document or to file any report / return when called upon to do so, the officer conducting inquiry may decide the applicability of Act and determine the dues from employer on the basis of evidence adduced during the inquiry and other documents available on record.
Mumbai HC in Savitri Pal Vs. State of Mah. given procedural guidelines for Quasi-judicial Authority.
Also in Lokmanya Nagar Priyasharshini Vs. State of Mah. given some parameter.
If you wish to practice in such matters and become an experts then read all those.
The write up which I have given here is sufficient enough to you to understand 7A inquiry and its' procedure. I have not discussed on many things such as setting aside ex-parte order, appeal etc. It is a vast subject to study.