Hello, Ideally, one should not be a member of two trade unions. However, if the check-off system has not been introduced in an organization, it is very much possible and seen in a few industries during my service period that the number of unionized workers is more than the total manpower of that particular unit/establishment. This can only be possible with the fact that a number of employees are members of more than one union.
Should you like to have more advice, you can communicate with me through email at [Email Removed For Privacy Reasons].
Best wishes,
Retired Manager (HR)
Coal India Ltd