These landmark rules aim to standardize and mandate use of Indian Standard Time (IST) across all sectors in India.

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

• 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.