Light Sensors on Shabbos
Question: Do I need to cross the road on Shabbos to avoid triggering a motion sensor light? Answer: The Mishna Berura (277:9) writes that one mustn’t open a door near a candle. As the breeze will inevitably fan the flame, this is considered to be pesik reisha denicha lei as one may benefit from this too. The Piskei Teshuvos (277:9) writes that this halacha applies equally to walking past a light that will be triggered by a sensor. Nonetheless, R’ Chanoch Padwa (Cheshev Haefod 3:83) and R’ Ephraim Greenblatt (Rivevos Ephraim 7:1231; 8:532:1) argue that when one isn’t interested in triggering someone else’s light it is considered to be pesik reisha delo nicha lei. Thus, they write that while it is ideal to avoid triggering such lights, one may walk past them if necessary. R’ Ribiat (The 39 Melochos, p1214) differentiates between a regular residential road and a rural area. Only if the street is lit up enough that one can see where they are going clearly is this extra light...