Free AutoCAD plumbing and fire protection symbols (DWG): pipes, drains, sprinklers, alarms

About the conventions

Plumbing and fire protection symbols are not fixed by a single standard: practice differs by country, discipline and office. Related standards are NFPA 170 for fire safety symbols and ISO 6412 for the simplified representation of pipelines, and most offices keep their own legend.

The blocks are our own drawings after common drafting conventions, not copies of a standard, and the library is not certified. Check the symbols against the legend of your project or the requirements of the authority, and change a block if yours differs.

Frequently asked questions

Do the symbols follow NFPA 170 or a national standard?

They follow common drafting conventions, so most of them will look familiar, but the library is not a certified implementation of NFPA 170 or of a national standard. Compare them with the legend your project or authority requires and change a block where it differs.

Can I use the blocks for a sprinkler schedule or a device list?

Yes. The sprinkler blocks have K-factor, temperature rating, response and coverage attributes, and the detector and alarm blocks have address, loop and location. Export them with BlockSync to Excel, complete the schedule and write it back to the drawing.

Can I use the symbols in commercial projects?

Yes. They are free to use and modify in your own projects, including commercial ones. They are provided as is, without warranty.

Are toilets, basins and other fixtures included?

No, this library covers the piping, valves, drainage, equipment and fire protection. The sanitary fixtures in plan and elevation are in the architectural plan symbol library, so use both libraries together on a plumbing plan.

Can I change a symbol or add attributes?

Yes. Open the DWG, edit a block with BEDIT to change it or add attributes, and save. To update drawings that already contain the block, run ATTSYNC or replace the block. Make a backup first: attribute values can be lost if ATTSYNC is used carelessly.

Where do I find a ready-made set of these symbols for AutoCAD?

AutoCAD itself ships only a small set of sample blocks, so a full symbol set has to come from a library. Download the ZIP on this page and open the DWG: every symbol is a block. Insert one with INSERT (Blocks palette, Libraries tab, then pick the DWG) or drag it from DesignCenter (ADCENTER). You can also download a single symbol on its own.