The Freedom of Mobilty
|Rabbi Yisrael Rozen, Engineer, Dean of Zomet Institute|
The Freedom of Mobilty
Halachic Adaptation of Electric Mobility Devices for Use on Shabbat and Holy Days
How did it all begin?
More than 20 years ago, the phone rang at my home in Alon Shevut, in Gush Etzion. Upon answering I heard, "This is Shlomo Zalman." I immediately recognized the voice of the most famous halachic authority in the world, Rabbi Shlomo Zalman Auerbach, from Jerusalem. He was the head of Yeshivat "Kol Torah", and widely known as the Posek Hador, the leading halachic authority of the generation (Rabbi Auerbach passed away on 20 Adar I 5755, 20.2.95, 10 years ago).
In the modest way that was so typical of him, the Rav asked if I could come to his house the next day to help him with something. I replied, "Certainly," very happy that I had been given this great honor.
The next afternoon, the rabbi asked me to accompany him to a dilapidated house in his neighborhood in Jerusalem, the neighborhood known as " Shaarei Chesed." When he knocked on the door, it was opened by a young girl, sitting in an electric wheelchair. "Can you use the expertise of The Zomet Institute to make some sort of arrangement for her to be mobile on Shabbat?" he asked, with a look of affection.
After we left her house, he added, "the young lady is a student, from a traditional Jewish family, and Shabbat is a very sad day for her instead of being a day of 'Oneg Shabbat,' as we have been commanded it should be. She cannot leave her house without an electric wheelchair."
"If the Rav will give us Halachic approval, I think we will be able to meet this challenge," I replied. And I immediately brought up some of the difficulties. "We are not talking about traveling with some Shabbat mechanism to a synagogue, since a woman is not required to pray in a congregation. Do I understand that she is interested in moving around on Shabbat for enjoyment, for such purposes as visiting friends, and so on?"
"Yes, certainly. Oneg Shabbat is a mitzva derived from the words of the prophets ('Declare Shabbat as a joy' [Yeshayahu 58:13]), and the ' gramma' solutions that you have developed in The Zomet Institute are suitable for disabled people, who are defined as sick and suffering in their whole body. Good luck in this task, I pray that G-d will be with you."
So, with the blessings of the famous Posek Hador, the idea was born: to find a techno-halachic solution for the disabled who cannot use their legs but need an electric wheelchair. We also turned to Rabbi Shaul Yisraeli, the head of Yeshivat Mercaz Harav in Jerusalem (who also passed away the same year, in the summer of 1995), and he promised to maintain an interest in the project as it progressed.
Excited at the prospect of being able to help these people enjoy Shabbat to the fullest, we established a task force at The Zomet Institute consisting of rabbis and engineers, with the goal of identifying all the practical problems and meeting the challenges one by one.
We visited the repair laboratories of the Ministry of Health and the Ministry of Defense (which takes care of disabled people in the IDF), and we also visited the "Yad Sarah" Organization, in order to get an in-depth understanding of the equipment and the different variations, and in order to see how it was used. We found that it was necessary to have halachic solutions for operating the main switch, for setting the direction of movement (forward/backward), for speed of motion, and for braking, in addition to other specific items that are needed for different models of wheelchair.
After a few months of strenuous work, we had a prototype wheelchair in The Zomet laboratories. The guinea pig for our tests was an elderly man (who has since passed away) from Kibbutz Yavneh who happened to turn to us at that time and who found that there was a solution under development.
The Techno-Halachic Principles Involved
There are two halachic principles which serve as the basis for this project: (1) Indirect operation, known as gramma; and (2) modulating an existing current.
This can be explained in more detail as follows. Work that is prohibited on Shabbat – whether by Torah command or by Rabbinical decree – is permitted in principle if the person does not "perform" the work but only indirectly "causes" it to happen. In the Talmud, the verse, "Do not perform any work" is interpreted as in principle allowing gramma,  an indirect operation. However, early commentators have written that this is permitted only in cases of great need. The RAMA writes that this is valid only in "a situation of loss." It should be noted that in the original source, in both the Mishna and the Talmud, the case being considered is extinguishing a fire, which is work whose direct byproduct is not wanted. However, it is written in the Mishna Berura that "this refers not only to extinguishing a flame, which is work whose byproduct is not needed, rather it is true for all work."
The fact that gramma is permitted in "a situation of loss" has been interpreted in recent generations to include not only financial loss such as a fire but also every other essential need, such as matters related to health and security. In fact, this has been extended to include anything related to health, which has been given a status on an equal footing with "a situation of loss" and often even greater importance. For example, see the most prominent and well accepted recent book about the laws of Shabbat, "Shemirat Shabbat K'Hilchata," by Rabbi Yehoshua Neuwirth, from Jerusalem (a disciple of Rabbi Shlomo Zalman Auerbach), who wrote about the subject of adjusting the tabs on a Shabbat timer, to delay or speed up the time that the electricity would come on. Here is what he writes:
"If the Shabbat timer was set during the day to stop the electric current at a specific time, it is permitted on Shabbat to do what is necessary so that the current will be stopped at a later time, but it is forbidden to make the current stop at an earlier time." However, he adds, in note 91, "But for the needs of a sick person, even if he is not in mortal danger, or for a matter related to a mitzva – it is permitted to make an adjustment so that the timer will turn the electricity off earlier, as long as one is careful not to turn it off manually."
This permission to operate electricity through gramma by having a timer operate earlier, for a sick person or for a mitzva, is the basis for our approval from many rabbis to permit a disabled person (or an elderly person who always uses a wheelchair) to operate the equipment on the principle of gramma. The brake on a wheelchair is also operated by this technique.
And this leads us to the next principle, which we have called "modulating (changing) an existing current." Not everybody is aware of this halacha, but if for example a radio or a two-way communication device is on during Shabbat, it is permitted to change the intensity of the sound. Modifying a current (or a voltage or a wavelength) does not violate any prohibition. It is important to note that this does not refer to a light (such as a halogen bulb, for example) or a heating element, which are considered to be "flames" – by Torah law it is forbidden to increase or decrease the level of a flame on Shabbat. It does refer to such things as the level of sound or the speed of a motor. Note also that operating these types of electrical devices is forbidden not because of the Shabbat violations of mav'ir (lighting a flame) and mechabeh (extinguishing) but rather boneh (construction), makeh bepatish (the final stage of construction), or molid ("giving birth" to something new). In all of these types of work, the prohibition is to make something new, like closing an electric circuit, but not in modifying something that already exists.
Thus, for example, with respect to hearing aids, it is permitted to adjust the intensity of the sound on Shabbat (as long as they are turned on for the entire duration of Shabbat). See "Shemirat Shabbat K'Hilchata," and various responsa that the author quotes, including Rabbi Moshe Feinstein. This is also the basis for the accepted ruling that closed circuit television may be operated on Shabbat from the point of view of the electricity involved (as long as it operates continuously and the picture is not recorded), since electronics involves nothing more than changes in current, voltage, and frequencies. See "Techumin" for discussions by Rabbi Feinstein and Rabbi Neuwirth, with my own comments and clarifications.
Thus, when the switch of a Shabbat version of an electric wheelchair is in the ON position, the motor is running continuously at a slow "crawling" pace. Any small friction will stop the chair from moving, including such things as the weight of a person. The rider changes the level of the current to the motor by adjusting a rotary switch, such that he or she can move by increasing or decreasing the current, as is needed.
And, The Happy Result Is...
Nowadays, hundreds of disabled and elderly people can be seen who happily move around on Shabbat using these Techno-Halachic devices. Many of them at first were inhibited by the appearance that they were desecrating Shabbat, and they were not comfortable in riding in a vehicle. Quite often their community rabbis gave them encouragement after receiving explanations and the background of the issues involved from The Zomet Institute.
On every wheelchair of this type there is a sign that explicitly states that "this chair is equipped with a halachically permitted Shabbat mechanism, approved by The Zomet Institute and prominent rabbis."
This equipment can be used lechatchila, as a desired solution and not only as a last resort. Rabbi Auerbach's disciple, Rabbi Yehoshua Neuwirth, has sent us various people who were in need of a solution to this problem. One time, Rabbi Neuwirth was asked by a man in London who needed a wheelchair for his fifteen-year-old daughter, "Should I use the Zomet system on Shabbat or push her by hand?" The father added that he was strong and would have no problem at all pushing his daughter if necessary. Rabbi Neuwirth replied, "This system is definitely permitted, and there is no reason for you to strain yourself. Even if you want to make the effort, your daughter will feel more comfortable if she can maintain her independence. This is also a consideration that must be taken into account by the halacha."
Translated by: Dr. Moshe Goldberg
 Shabbat 120b: "Do not perform any work [Shemot 20:9]" – performing work is forbidden, gramma is permitted.
 It is important to note that some types of work are by nature continuous, something of a natural state of gramma, and they are therefore not permitted on Shabbat.
 Shulchan Aruch Orach Chaim 334:22, in the name of the Mordechai.
 Bi'ur Halacha 334:22.
 Shemirat Shabbat Kehilchata 13:25.
 Published by Zomet Institute. See volume 14, page 432 and following. G-d willing, a new article by Rabbi Z.N. Goldberg will be published in volume 25, now in press.