9015 - Surveying (including photogrammetrical surveying), hydrographic, oceanographic, hydrological, meteorological or geophysical instruments and appliances, excluding compasses; rangefinders; parts and accessories thereof:

Category 9015 encompasses a broad range of instruments and appliances specifically designed for surveying, mapping, and the scientific measurement of environmental conditions. This includes devices used in terrestrial and aerial surveying, such as those for measuring distances and angles, as well as instruments for the systematic observation and recording of data related to water bodies (hydrology and hydrography), weather patterns (meteorology), and the Earth's physical properties (geophysics). While the broader Chapter 90 covers various precision instruments, 9015 is distinct in its focus on applied scientific measurement and spatial data acquisition rather than general laboratory equipment or diagnostic tools.

This HTS category is distinguished from its siblings in Section XVIII by its specialized application in surveying and environmental science. For example, instruments solely for timekeeping (Chapter 9015 includes some timing components for surveying instruments but not standalone timepieces), optical instruments for general viewing (Chapter 9001-9004), or tools for general mechanical measurement are classified elsewhere. Instruments like compasses, while used in surveying, are explicitly excluded from 9015 and fall under their own specific headings.

Within 9015, further subdivisions refine the classification based on the primary function of the instrument. These include dedicated categories for rangefinders (9015.10), theodolites and tachymeters (9015.20) for angular and distance measurements, levels (9015.30) for determining horizontal planes, and specialized photogrammetrical surveying instruments (9015.40) used for creating maps from aerial photographs. The "Other instruments and appliances" (9015.80) category captures a variety of specialized devices not otherwise specified, and a dedicated subheading for parts and accessories (9015.90.01) ensures that components of these complex instruments are appropriately classified.