There is no set schedule for how often stainless steel narrow crown staples need to be inspected and replaced, as it depends on the application and environmental factors. However, here are some general guidelines:

Outdoor applications:

Inspect staples annually in autumn/winter when vegetation is dormant. Replace any that are severely rusted, bent, or loose. High moisture or salty air locations may require more frequent attention.

Indoor applications:

Inspect every 2-3 years. Staples indoors see less weathering so may last longer, but movement and vibration can still cause deterioration over time.

Heavy use areas:

Hightraffic spots may need yearly checks due to increased abrasion and stresses on the staples. Replace as loose or worn staples are found.

Structural applications:

Anything load-bearing like roofing should be examined annually at a minimum. Immediate replacement is prudent for any compromised staples.

Remote locations:

Set a calendar reminder to check hard-to-access areas every 2-5 years depending on environment. Replace staples as condition requires.

New installations:

Inspect following seasonal extremes in the first 1-2 years to establish baseline longevity. Adjust schedule based on findings.

So in summary, annual inspections for outdoors and high-use, every 2-3 years for low-use indoors, or as conditions warrant. Replace problem staples promptly.