BAS point naming conventions
By Bassirou Thiam, building automation engineer · Updated
A good BAS point name is unique, readable and built the same way everywhere: typically site or building, then equipment tag, then point abbreviation, such as B1-AHU1-SAT. The same name appears in the controller, on the front end, in the points list and in the sequences. Tagging standards like Project Haystack add machine-readable meaning on top.
What do specs require?
Owner and guide specifications often fix the format. One typical spec requires every point, panel and program to carry a 30-character name and a 16-character descriptor, displayed identically at the controller and at the operator interface. Many universities and agencies publish their own naming standard: check the owner's before inventing one.
A structure that works
| Part | Example | Note |
|---|---|---|
| Building or site | B1 | Needed on multi-building campuses |
| Equipment tag | AHU1, VAV-2-14 | The tag on the mechanical drawings |
| Point | SAT, SF-SS, CHW-VLV | A short, documented abbreviation |
Keep one separator, no spaces, and a published list of abbreviations so every technician writes the same thing.
Common abbreviations
| Abbreviation | Meaning |
|---|---|
| SAT / RAT / MAT / OAT | Supply, return, mixed and outside air temperature |
| SF / RF / EF | Supply, return and exhaust fan |
| SS / STS | Start/stop, status |
| CHWS / CHWR | Chilled water supply and return |
| HWS / HWR | Hot water supply and return |
| DSP | Duct static pressure |
| OAD | Outside air damper |
Names versus tags
A name identifies a point; tags describe what it is. Project Haystack adds tags such as air, temp, sensor and supply to each point; Brick models how points, equipment and spaces relate. ASHRAE's proposed Standard 223P, a semantic data model for buildings, has gone through public review drafts with input from both communities. Tags do not replace a clean naming rule: they sit on top of it.
Sources
- Siemens, guide specification Section 23 09 00 – Building Automation System (submittals, network, point naming)
- WBDG, UFGS 23 09 00 – Instrumentation and Control for HVAC (U.S. Department of Defense)
- Project Haystack, open tagging standard for building data
- Brick Schema, open semantic model for buildings
- U.S. Department of Energy, ASHRAE Standard 223P