Final answer:
4) Every year The correct answer is that under the SSI equipment service program, the delivery system should be serviced every year to ensure safety and proper functioning.
Step-by-step explanation:
The correct answer is option 4) Every year. Under the SSI equipment service program, it's recommended that your delivery system be serviced annually. This is to ensure that all the components are functioning properly and are up to the manufacturer's standards.
Regular maintenance is crucial for the safety and reliability of the equipment, particularly in demanding activities such as scuba diving. Even though individual usage and local conditions might require more frequent servicing, SSI sets a general guideline of once a year as a minimum standard for service checks.
An annual service typically includes inspection, cleaning, and replacement of worn parts.