How is the service life of a discharge cartridge calculated?

• A. From the date stamped on the cartridge by the manufacturer.
• B. From the date of installation.
• C. From the date of last maintenance.
• D. From the date of purchase.

Answer: (A)

The service life is determined from the date stamped on the cartridge by the manufacturer. That stamp marks the actual manufacturing date, which is the starting point for aging the energetic materials and seals inside the cartridge. Even if the cartridge sits in stock or is installed later, the aging clock starts at manufacture, so using the manufacturer’s date ensures you’re applying the official shelf life for reliability.

Using the installation date would ignore the time the cartridge spent aging before installation, and the date of last maintenance or purchase doesn’t reflect how long the cartridge has aged or been stored. The manufacturer’s date is the only date that consistently represents the cartridge’s age and expected performance.