I believe this may be a 3 way switch. I think some of my lab manuals had it drawn this way at times. I could be wrong, just a student here!
After looking at one of my lab manuals, I think I may be wrong and have to retract my guess. The 3-way switch is similar but the arrow is drawn upwards from the middle line in the manual. However, I have been told that some companies/institutions will draw symbols a bit differently than the standards.