Dear Timmu,
The lofty purpose behind the statutory requirement of insurance under the ESI Act,1948 is to provide for certain benefits to employees in case of sickness, maternity and employment injury so that the employer stands relieved of his liability in this regard. By virtue of the salary limit, if some employees escape the coverage of the ESI Act,1948, the liability of the employer to compensate such employees in respect of death or injuries due to any employment accident or contracting of any occupational disease remains still at large under the Employees Compensation Act,1923. Though, it is not mandatory under the EC Act,1923, it is always safe to take employees compensation insurance policy in respect of those employees not covered by the ESIAct,1948 but falling under the definition of employee u/s 2(dd) of the ECA,1923.