Before attempting a repair the tire must be removed from the rim/wheel assembly. then a trained technician must completely inspect the tire and asses all damage that may be present, including damage to the inner lining.
For safety and durability, Thomas Tire & Automotive follows the U.S. Tire Manufacturers Association's guidelines for puncture repairs:
Repairs are limited to the tread area only (see graphic).
Puncture injury cannot be greater than 1/4-inch (6mm) in diameter
A rubber stem, or plug, must be applied to fill the puncture and a patch
Not all tires can be repaired. Specific repair limits are based on the recommendations and repair policy of the tire manufacturer.
A tire that has a improper preexisting repair cannot be repaired. It must be scrapped.
An outside-in tire repair or on-the-wheel repair can never be performed.
Learn more about safe tire repairs here
