Elevator Shabbos

Igros Moshe (OC II #80) Question: There is a large building in which most of the space is rented for offices which are used on Shabbos and Yom Tov and there is an elevator operated by a non Jew. Now the owner wants to change this so the elevator is self service Is this change prohibited because it is causing Jews to sin? Answer Before the elevator was operated by the non Jew there was no concern for lifnei Ivair since there were other offices elsewhere that could be rented. And thus it was only a question of allowing sin and the Magan Avraham says this is not a problem since most use does not involve sin.  However now that a non Jew has been hired to run the elevator and it would require a major effort for the tenants and might be impossiuble  to move elsewhere it is now a problem of lifnai ivair if you switch to self service and thus it seems it should be prohibited. However I have shown regarding Sheviis that whenever the work involved can be sometimes prohibited and other times permitted it is permitted to sell a field or an animal that will sometimes be involved in sin but not all the time. Thus it is not viewed as causing or supporting of  allowing sin. But merely being a minor causation that sin is done and this is not prohibited.  However while I was inclined to permit based on this reasoning I didn’t actually pasken that it was permitted since I couldn’t find anyone who actually ruled according to this principle. Nevertheless if not permitting will result in a large financial losss it can be relied on to permit. Even the use of the non Jew violates a Rabbinic prohibition if he is acting entirely because he was hired to work for the owner. It is better that he work primarily for himself. For example if he get paid a specific amount for each trip and thus the prohibition is not caused by the owner

Igros Moshe (OC II #95) It is prohibited to enter an elevator on Shabbos that an evil person entered into first. However if a goy enters first for his own needs it is technically permitted but is prohibited because of maris haaiyen. In addition it is prohibited because additional people that enter increase the work done by the motor. Furthermore if he is known as a G-d fearing person and surely as a talmid chachom use of the elevator is also a chillul haShem 

Igros Moshe (OC IV #64.1) It is prohibited to use electricity on Shabbos and Yom Tov even though  it doesn’t make a fire . Similarly a refrigerator or freezer is prohibited and obviously it is prohibited to turn on electric lights. 

Igros Moshe (OC V #18.27) It is prohibited to comb hair on Shabbos because it is impossible without pulling out hair. The Magen Avrahan says even according to the view that an inevitable action which is unwanted is permitted this is prohibited because you want to separate the hairs and it is impossible do do it without pulling out some hair. This Magen Avraham supports my view regarding the sparks produced when an electrical circuit is completed or disconnected with any electrical device. Similarly when increasing the load on an electric motor such as in an elevator. So even saying that the sparks serve no necessary purpose and you don’t want them however since it is impossible to obtain the use of electrical power for the elevator without them so the sparks are not considered an inevitable  side product but rather are viewed as an integral part of the elevator and are prohibited