Context: In a move to standardize timekeeping, the government has drafted comprehensive rules mandating the exclusive use of Indian Standard Time (IST) across all official and commercial platforms, the Department of Consumer Affairs notified.

• The Legal Metrology (Indian Standard Time) Rules, 2025, aims to establish a legal framework for standardising timekeeping practices, mandating IST as the sole time reference for legal, administrative, commercial, and official documents.

About Draft Legal Metrology (Indian Standard Time) Rules, 2025 

• The government has drafted rules mandating the exclusive use of Indian Standard Time (IST) across official and commercial platforms to standardize timekeeping. 

• IST will be the mandatory time reference for legal, administrative, commercial, and financial operations, with exceptions for specialized fields subject to approval.

• Mandatory time reference: Would be IST across all sectors, including commerce, transport, public administration, legal contracts, and financial operations.

• Prohibition: No person/entity shall use, display, or record time other than IST for official/commercial purposes.

• Provided that any law/government direction/guidelines permits same.

• Adoption of Time Synchronization Protocols: Such as Network Time Protocol and Precision Time Protocol etc. by government offices is required. 

• Cybersecurity: To ensure resilience, cybersecurity measures and alternative reference mechanisms are prescribed.

• Authorized Deviations: Use of alternative timescales (GMT, etc.) is permitted for specific purposes e.g. astronomy, navigation, scientific research, etc. subject to prior permission.

Significance of New Draft Rules

• Strengthens national security by improving the synchronization of critical infrastructure

• Synchronization of digital devices and public services ensures reliable and efficient services

• Will ensure accurate financial transactions and consistency in record-keeping

About IST

• Central meridian of country (i.e. 82°30’E meridian passing through Mirzapur) is taken as Standard Meridian or IST (Maintained by CSIR-NPL).

• It is 5 hours 30 minutes ahead of Greenwich Mean Time (GMT) (now Universal Coordinated Time (UTC)).

• Local time at Prime Meridian (0° longitude) is known as GMT.

Longitude and Time

• Longitude of a place is its angular distance east or west of Prime Meridian which passes through Greenwich, England.

• Earth completes one full rotation (360°) on its axis in 24 hours, which means it rotates 15° per hour or 1° in 4 minutes.

• Countries often use a Standard Meridian (a longitude divisible by 7° 30’) as a reference for their time zone.

• So that difference between its standard time zone and Greenwich Mean Time may be expressed as multiples of an hour or half an hour.