The Limited Alteration Application (LAA) is used for plumbing work, fire suppression piping replacement and repairs, and oil burner installations that do not include construction work. Generally, with the exception of some new installations, LAAs are restricted to repair and/or replacement work for existing appliances and piping systems that do not require a Professional Engineer (PE) or a Registered Architect (RA).
https://www1.nyc.gov/site/buildings/industry/limited-alteration-application.page