Explain the applicability of Cost Audit as per Rule 4 of the Companies Act, 2013.

The companies required to include cost records in their books of account in accordance with sub-rule (1) of the Companies (Cost Record and Audit) Rules, 2014, shall be required to get such cost records audited by a cost auditor. Every company specified in item (A) of rule 3 of the Companies (Cost Record and Audit) Rules, 2014 shall get its cost records audited in accordance with these rules if the overall annual turnover of the company from all its products and services during the immediately preceding financial year is rupees fifty crore or more and the aggregate turnover of the individual product or products or service or services for which cost records are required to be maintained under rule 3 is rupees twenty five crore or more. Every company specified in item (B) of rule 3 of the Companies (Cost Record and Audit) Rules, 2014 shall get its cost records audited in accordance with these rules if the overall annual turnover of the company from all its products and services during the immediately preceding financial year is rupees one hundred crores or more and the aggregate turnover of the individual product or products or service or services for which cost records are required to be maintained under rule 3 is rupees thirty five crores or more. The requirement for cost audit under these rules shall not apply to a company which is covered in rule 3; and- whose revenue from exports, in foreign exchange, exceeds seventy five per cent of its total revenue; or which is operating from a special economic zone; which is engaged in generation of electricity for captive consumption through Captive Generating Plant. For this purpose, the term 'Captive Generating Plant' shall have the same meaning as assigned in rule 3 of the Electricity Rules, 2005'. Even for regulated sectors like Telecommunication, Electricity, Petroleum and Gas, Drugs and Pharma, Fertilizers and Sugar cost audit requirement has been made subject to a turnover based threshold of ₹ 50 crores for all product and services and ₹ 25 crores for individual product or services. For non-regulated sector the threshold is ₹ 100 crores and ₹ 35 crores, respectively.