A Pollution Under Control (PUC) certificate is mandatory for all vehicles operating on Indian roads. It indicates that the vehicle's emissions comply with environmental standards and do not exceed safety levels.

Validity Norms:
- For new vehicles, a PUC certificate is issued valid for 1 year from the date of registration.
- After the first year, all vehicles (BS4 & BS6 compliant) must undergo testing every 6 months or 1 year depending on state rules.
- Testing is done at authorized pollution check centers using smoke analyzer probes.

Fines & Penalties:
Driving a vehicle without a valid PUC certificate is a serious offence, attracting a fine of ₹10,000 under Section 190(2) of the Motor Vehicles Act, along with suspension of the driving license for 3 months.