Summer 2024

Historians claim that two hundred and twenty-four slaves were needed to operate the pulleys of the elevator system in the Colosseum of Rome. Thankfully, technology has come a long way since then. Modern elevators run on electricity which has necessitated the development of a Sabbath Mode. In Sabbath Mode, an elevator cab moves continuously up and down the elevator shaft, stopping at every floor. However, as will be explained, not all Sabbath Modes are the same.

Physics 101: How Elevators Work

There are two basic types of elevators in common use today: hydraulic and traction.

Hydraulic-Type Elevators

Hydraulics make use of the principle that liquid moved with low force over a large distance can be converted to movement with high force over a short distance. Take, for instance, a simple hydraulic jack (see Fig. 1). If the piston on the right has a surface area ten times that of the piston on the left, when force is applied to the left piston, it will move ten units for every one that the right piston moves. If a person pumps the left piston enough times, he will be able to slowly lift a load.

A hydraulic elevator works the same way. Hydraulic fluid, which is stored in a tank, is pushed by an electronic pump to drive a piston, which in turn moves the elevator cab up an elevator shaft (see Fig. 2). To lower the cab, the elevator controller opens electronic valves to drain the hydraulic fluid back into the tank, lowering the piston and thereby the cab.

Traction-Type Elevators

To understand this mechanism, think of a playground seesaw. When two children sit on opposite ends of a seesaw, the difference in weight is minimal; a small push is sufficient to propel one child up and the other down. Similarly, the cab of a traction elevator is attached to steel cables which run up the elevator shaft and over a pivot, with a counterweight on the other side (see Fig. 3). The weight difference is minimal; an electric motor pulls the cables to move the cab up and down the shaft.

Using an Elevator on Shabbos

As with all electric machines, it is forbidden to initiate use of an elevator on Shabbos. One cannot push a button to call an elevator and one cannot press a button inside the elevator to select a floor.

An elevator in Sabbath Mode avoids these issues by stopping on every floor. The Minchas Yitzchok forbids even this, because the rider’s additional weight causes the elevator motor to work harder and draw more current.[1] Rav Eliyohu Henkin zt”l, however, disagrees and allows the use of this type of elevator on Shabbos.[2] Rav Shlomo Zalman Auerbach zt”l is also lenient. He points out that any electrical change will only occur sometime after the rider enters the cab, once the elevator starts moving.[3]

Rav Levi Yitzchok Halperin zt”l, founder of The Institute for Science and Halacha in Yerushalayim, did extensive research and wrote a book on this topic titled Maliyot Be’Shabbat. Rav Halperin’s conclusion is that one may use an automated elevator on Shabbos to ascend but not to descend. He argues that, during descent, the weight of the person in the elevator cab assists the motor. Thus, the person contributes to the function of the lights, brakes, door motor and other electric circuits which are activated.[4]

Rav Shlomo Zalman takes issue with Rav Halperin’s thesis.[5] He makes several arguments to support his position:

• There is no noticeable difference in the running of the elevator when a person enters the cab, and any change that he causes is therefore not halachically significant.
• Any potential change is merely caused by the weight of his body as he passively stands in the elevator, and not by any action of his.
• There is no immediate effect when he enters the elevator, and any change will only occur sometime later when the elevator starts moving.
• He alone cannot move the elevator at all, whereas the electricity can move the elevator without his help. As such, his assistance is not halachically significant.

It should be noted that there are poskim who feel that the use of an elevator is a “weekday activity” and that the sanctity of Shabbos precludes the use of all elevators.[6] In a teshuva, Rav Shmuel Wosner zt”l writes that he personally is hesitant to be lenient in any circumstance, but he does not object if others are lenient and allows the use of a Shabbos elevator in extenuating circumstances.[7]

A number of poskim allow the use of a Shabbos elevator for a choleh.[8] STAR-K Rabbinical Administrator Rav Moshe Heinemann shlit”a paskens that a healthy and mobile person should avoid using a Shabbos elevator, but an elderly or infirm person may be lenient.

Modern-Day Elevators 

Sabbath Mode elevators which stop at every floor eliminate the need to press buttons on Shabbos. There are, however, several other halachic concerns that must be addressed before using a modern-day elevator on Shabbos. Here are some of the key issues: 

► Door Edge Sensors 

Elevators typically feature an infrared mechanism known as the door edge sensor, which detects when a person is blocking the doorway. This poses a concern on Shabbos, as merely walking through the doorway triggers the infrared mechanism and the various relays and LED indicators on the control panel (see Fig. 4).

► Releveler Sensors 

Hydraulic elevators experience slight sinking and rising when passengers enter or exit, which is detected by encoders or magnetic tape readers/selectors. This detection prompts hydraulic pumps or valves to relevel the elevator, as well as to activate LED indicators and relays on the control panel.

► Motor Speed Encoders 

Some elevators are equipped with encoders that ensure motor speed compliance. These encoders monitor the motor speed to prevent it from exceeding specified limits. Movements within the cab  – such as entering, exiting or shifting – will trigger new readings on the encoder, activating LED indicators on the control panel.

► Floor Selector Encoders

Encoders also detect the elevator’s position relative to the floor, allowing the elevator to slow down as it approaches the desired floor. Similar to motor speed encoders, the floor selector encoders detect movement within the cab which can trigger new readings; they, too, may activate LED indicators and relays on the control panel.

► Load Weighing Devices 

New regulatory requirements mandate the inclusion of load weighing devices in new and remodeled elevators to prevent overload situations. These devices continuously measure the weight of the elevator cab, with some systems having back-end displays – not visible to passengers. Even minor movements within the cab can result in fluctuations in the displayed weight readings (see Fig. 5).

► Automatic Deactivation of Sabbath Mode 

In some cases, the Sabbath Mode does not run during the duration of Shabbos in order to minimize power consumption and the risk of motor burnout. In that event, Sabbath Mode is set to be operational according to a specific schedule. One who enters an elevator while Sabbath Mode is operational will have no halachically sanctioned way to exit should the Sabbath Mode deactivate.

Halachic Concerns and Solutions

Do visible changes to the elevator control panel, activation of LED indicators and electric relays pose a halachic concern on Shabbos?[9] Rav Heinemann paskens that they do pose a halachic concern, and that all changes to the LED indicators, display, relays, and weight readings should be disabled if possible. It is also necessary to ensure that the door will not start to close and reopen when a passenger enters the elevator.[10]

To address these concerns, solutions for a halachically sound Sabbath Mode include:

• disabling the door sensor while the doors are open
• disabling level sensors while the doors are open
• disabling the weighing system while the doors are open 
• installing a visual and/or audible warning before the doors close to inform passengers not to enter or exit the cab at that time
• indicating that the Sabbath Mode is about to deactivate, allowing passengers to exit in time
• disabling LED lights and displays in the control room

Clearly, not all Sabbath Mode elevators are the same. While some elevators come with a Sabbath Mode that causes the elevator to stop at every floor, their Sabbath Mode may not address the various halachic problems cited above.

GramaChip Technologies is a STAR-K certified company that offers a range of custom Sabbath Mode products. GramaChip Technologies modifies elevators by providing a Sabbath Mode that comprehensively addresses all the halachic issues associated with modern-day elevators. They collaborate closely with elevator companies and installers to ensure full technical compliance. For more information, they can be reached at 732-655-4206 or [email protected].

---

[1] שו”ת מנחת יצחק ח”ג סי’ ס

[2] שו”ת גבורת אליהו או”ח סי’ קז (הערה קסד במהדורה החדשה)

[3] שמירת שבת כהלכתה פרק כג הערה קיז

[4] הספר מעליות בספר לר’ הלפרין נמצא באתר אוצר החכמה.  בסוף הספר יש שני מאמרים קצרים באנגלית:

The Sabbath Elevator Question – A Technical Analysis of a Halakhic Problem” by D. R. Bannett “Passenger Responsibility for Descent – A Halakhic Analysis” by Rabbi Yechiel Neumann

המאמר הראשון נמצא ג”כ באתר https://nzautomacao.com.br/files/Ema’aliot%20new.pdf

[5] שמירת שבת כהלכתה שם הערה קמ (הערה קסו במהדורה החדשה)

[6] עי’ שו”ת חלקת יעקב או”ח סי’ קמד

יש קול קורא נגד ההשתמשות במעלית שבת עם החתימות של הגרי”ש אלישיב זצ”ל והגר”ח קנייבסקי זצ”ל והגר”ש ואזנר זצ”ל, נמצא באתר http://www.rabbibrand.022.co.il/BRPortal/br/P102.jsp?arc=36128

[7] שו”ת שבט הלוי ח”ו סי’ לט

[8] עי’ בספר פסקי תשובות סי’ רמ”ח ס”ק ב במהדורה החדשה

[9] יש כמה סברות להקל, שהרוכב במעלית שבת אינו יודע מכל זה והרי הוא מתעסק בעלמא, ואף שמתעסק בכל התורה אסור עכ”פ מדרבנן י”ל ששבת קיל טפי מפני שאין זה מלאכת מחשבת כמש”כ בשו”ת רע”א קמא סי’ ח, ועוד שהרוכב אינו מעונין בכל זה והרי הוא פסיק רישא דלא איכפת ליה באיסור דרבנן (וכ”כ בשו”ת יביע אומר חי”א סי’ כד להתיר מעלית שבת מטעם זה), ועוד שאין בזה צורת מלאכה כמש”כ כעי”ז בשו”ת שבט הלוי ח”ט סי’ סט.  מאידך גיסא, קי”ל שגם פסיק רישא באיסור דרבנן אסור כמש”כ השעה”צ סי’ שלז ס”ק ב, וגם יש לומר שמי שיש לו מעלית בביתו ניחא ליה שיפעל כראוי (ור’ משה היינעמאן שליט”א אמר בשם הגרי”ש אלישיב זצ”ל, שאף הנורות LED קטנות הנדלקות בחדר בקרה כדי שידע הטכנאי שהמעלית עובד כראוי, יש להם דין פסיק רישא דניחא ליה לבעל הבית, כיון שרוצה בהפעלתם כדי שידע הטכנאי אם יש איזה בעיה), ועוד שהרוכב יודע מזה כשהוא גורם לפתיחת הדלת מחדש וכדומה וניחא ליה בזה, ואכמ”ל.

[10] שמעתי מר’ משה היינעמאן שליט”א