Dear Sandeep,
In continuation of the replies of our learned friend Rkn61, I would like to state that the right to strike is not a fundamental or absolute right in India under any special or common law irrespective of the establishment being an industry or not.
So far as industrial workmen are concerned, the Industrial Disputes Act,1947, by classifying the industrial establishments into Public Utility Services and others, thereby imposes certain restrictions under sections 22 and 23 on strikes and lock outs and general prohibition of strikes and lock-outs respectively.
For the sake of convenience of narration with specific reference to the doubts raised in your query, let me restrict my reply to " strike" only and leave out " lock-out" being a similar action usually taken by the employers as a counter-measure with similar statutory restrictions only.
The term " Public utility service " has been defined u/s 2(n) of the ID Act,1947 so as to mean and include every establishment engaged in essential services like transport, communication, public conservancy and health, supply of power, light or water to the public and any industry specified in the First Schedule as such and any section of an industrial establishment, on the working of which the safety of the establishment or the workmen employed therein depends as well. Therefore, the restrictions u/s 22 would equally apply to any section discharging the duties/functions of such nature in a non-public utility service establishment too.
A strike would be legal if it does not violate the restrictive conditions imposed by sections 22 or 23 as the case may be.
Similarly, a strike would be illegal if it violates the two conditions specified u/s 24(1) of the Act.
Coming to section 22 of the ID Act,1847, everyone who goes through the section for the first time would be naturally a bit confused because of the phraseology of the same being interspersed with certain numbers of days and weeks. Hence let me simply put it as follows:
NO STRIKE IN PUBLIC UTILITY SERVICE [Sec.22] -
(a) Without giving to the employer a notice of strike, within 6 weeks before striking. In other words, from the date of notice to the date of strike, a period of 6 weeks should not have elapsed; OR
(b) Within 14 days of giving such notice i.e., a period of 14 days must have elapsed from the date of notice to the date of strike; OR
(c) Before the expiry of the date of strike specified in any such notice i.e., the date specified in the notice must have expired on the day of striking; OR
(d) During the pendency of any conciliation proceedings before a conciliation officer and 7 days after the conclusion of such proceedings.
GENERAL PROHIBITION OF STRIKES [Sec.23] -
NO STRIKE -
(a) During the pendency of conciliation proceedings before a Board and 7 days after the conclusion of such proceedings.
(b) During the pendency of proceeding before a Labor Court, Tribunal or National Tribunal and 2 months after the conclusion of such proceedings.
(bb) During the pendency of arbitration proceedings before an Arbitrator and 2 months after the conclusion of such proceedings.
(c) During any period in which a Settlement or Award is in operation in respect of any matters covered by the Settlement or Award.
I think the previous answer clearly explains the illegality of a strike.