Revision of the Indian Standards on Passenger and Goods Lifts, Part 1

Your authors describe coming changes to codes.

by Abhijit Dandekar and Pravin Tipnis

Abstract: The Indian Standards on lifts have been in existence for a long time. The current series of Lift Standards, namely IS 14665 Part 1 to Part 5, was published in the years 1999 to 2001, replacing the then-current standards IS 4666, IS 1860, IS 3534, and other component standards. The Indian Standards on Special lifts, e.g., lifts for Persons with Disabilities, Hydraulic Lifts, Home lifts, and Machine-Room-less lifts, etc., were added subsequently. Now, another big revision to the lift standards based on ISO 8100-part 1 and ISO 8100-part 2 is in the offing. This revision, currently under printing, will take the present Indian Standards on lifts to the international level. This article highlights the safety improvements the new proposed revision to the Indian standards on lifts will bring in, as compared to the existing lift standards, for the attention and benefit of the people in the lift industry, as well as interested members of the general public. In addition, the revision will open the possibility of using state-of-the-art technology “PESSRAL” in the control of lift operations. The revision standard part 2 will include guidance on a lot of critical calculations, such as traction between ropes and sheave, rope safety factor, etc., and specify type-tests for the critical safety components of the lift installation. This article also highlights the major differences in the revision documents with respect to the ISO 8100-1 and ISO 8100-2. Included are the recent additions of new standards on the subject and what to expect on this front in the near future.

Introduction

The vertical-transport (VT) industry in India has been largely regulated by the Bombay Lift Act 1939 and Bombay Lift Rules 1958 and revised from time to time. As of now, there are 11 states and one union territory that have enacted their own Lift Act and framed rules thereunder. In addition, the Bureau of Indian Standards (BIS) has published several Indian Standards on Lifts and Escalator. Typically, the Indian Standards are voluntary in nature. A few standards are made mandatory for the BIS mark to protect consumers’ health and safety, and a few others are covered under the compulsory registration scheme. However, some states, e.g., Kerala, Tami Nadu, Karnataka, Jharkhand and Haryana, have incorporated clauses in their respective Lift Act and Lift Rules making compliance to the relevant latest Indian Standards on lifts and escalators compulsory. Lifts and escalators are regulated through the National Building Code of India, as well.

The list of Indian Standards currently available on lifts is given in the Annexure 1 (to be published in ELEVATOR WORLD India, 1st Quarter 2022). These standards have been developed over a long period of time. The current standards in the series IS 14665 part 1 to part 5 were published in the years 1999 to 2001, which replaced the then-current standards such as IS 4666, IS 1860, IS 3534, and several other lift component standards.

Revision of the Core Indian Standards on Lifts 

The listed standards in the Annexure 1, except IS 14665 Part 5: INSPECTION MANUAL, and IS 15259 – INSTALLATION AND MAINTENANCE OF HOME LIFTS – CODE OF PRACTICE, are proposed to be superseded/revised by the Indian Standards (under development) based on ISO 8100-1: Lifts for the transport of persons and goods — Part 1: Passenger and goods passenger lifts; and ISO 8100-2: Lifts for the transport of persons and goods — Part 2: Design rules, calculations, examinations and tests of lift components. 

The main aim of revising the existing Indian standards on lifts is to bring them up to par with the international standards. The adoption of the new proposed standards will result in several advantages, such as enhanced safety for the lift passengers and lift service technicians; and the possibility of using the latest state-of-the-art technology “Programmable Electronic Systems in Safety Related Application for Lifts” (PESSRAL).

The Indian standard on hydraulic lifts, IS 14671: CODE OF PRACTICE FOR INSTALLATION AND MAINTENANCE OF HYDRAULIC LIFTS, was published in 1999. On adoption of the revision documents based on ISO 8100-1 and ISO 8100-2, the Indian standard IS 14671 is proposed to be superseded, bringing in a lot of improvements in the safe operation of hydraulic lifts, as well.

Safety Improvements Related to Lift Passengers 

Several new features proposed in the revision documents that will enhance the safety of lift passengers:

Ascending Car Overspeed Protection (ACOP) means: The revision documents mandate that lifts be provided with speed-monitoring and stopping devices so that in case of overspeed in the up direction, the lift will be stopped, or at least its speed will be reduced to a level not exceeding the buffer design speed.

The braking could be engaged by the safety gear fitted to the car or counterweight, or the rope brake, or the brake acting on the friction sheave. Even the regular machine brake may be used, provided it complies the requirements as per the ISO 8100-1 having redundancy and its self-monitoring is ensured.

Self-monitoring shall be ensured by verification of correct lifting/release of the brake or verification of the braking force.

Speed monitoring could be done by the speed governor or another device fulfilling the requirements.

The ACOP means is subject to type test.

This is a requirement partially covered in IS 14665. IS 14665 requires the speed governor to act in case of overspeed in either direction of travel of the lift; remove power from the machine, brake and thus apply the brake.

2) Unintended Car Movement (UCM) with landing door not locked and car door not in closed position: Requirements related to UCM: Lifts shall be provided with a mechanism to detect and stop unintended car movement away from the landing with the landing door unlocked and the car door open due to any single failure of the lift machine or drive control system, excluding failures of the ropes and the traction sheave, including a sudden loss of traction. 

This is a completely new requirement, which was not covered in IS 14665, that prevents likely accidents due to unintended movement of the lift car with the doors open.

The stopping element could act on the car, counterweight, ropes (suspension or compensation) or traction sheave, etc. The regular machine brake may be used, provided it complies with the requirements as per the ISO 8100-1 having redundancy and self-monitoring is ensured.

The car shall be stopped such that when passengers come out, there is sufficient space between the lift car floor and the lintel of the landing door; the landing floor and the lintel of the car door for the passengers to come out of the car; and, at the same time, there is no possibility of anybody falling in the pit due to an excessive gap between the car floor/car apron and the lift landing floor. The UCM system is subject to type test. This is a totally new requirement when compared with those of IS 14665.

3) Car door, landing door, landing/car door locking device and car wall strength: The car door, landing door and car wall shall be able to resist 1000 N over an area of 100 cm², against the current IS requirement of 345 N. Doors must include retainers to keep the door panels in place if the guiding elements malfunction. In addition, car doors, landing doors and car walls must be able to withstand an impact force equivalent to a person colliding at running speed. Toward this end, they shall withstand a defined “soft pendulum test.” In case of a door and car body having glass panels, an additional, defined “hard pendulum test” must be complied with. These pendulum shock tests are completely new additions when compared with IS 14665.

The landing/car door lock shall withstand a force of 1000 N at the level of lock in case of sliding doors, and 3000 N on the locking pin in case of hinged doors without permanent deformation or breakage that would adversely affect the safety. A force of 300 N in the opening direction of the door shall not diminish the effectiveness of the locking. Minimum engagement of the locking elements shall be 7 mm. An emergency unlocking triangle is defined, thus now standardized. These are new additions when compared with IS 14665.

4) Fire classification for lift car materials: The lift car material used for flooring, walls and ceiling shall be of a type that is not easy to ignite, shall be good in terms of flaming droplet properties, flame retardant, etc. IS 14665 does not specify such properties.

5) Car emergency light: The revision document specifies emergency lighting levels in the lift car. The lighting in the car shall provide a minimum illumination of 100 lux in normal conditions and 20 lux for one hour in an emergency situation. IS 14665 does not specify any values toward this parameter.

Safety Improvements for Service Engineers

1) Shaft lighting shall provide a minimum of 50 lux 1 m above the car roof vertically, 1 m above the pit floor anywhere a person can stand, work or move between work areas; and 20 lux elsewhere, excluding any shadows. As against this, IS 14665 does not specify any illumination levels at these locations.

2) Emergency lighting on the car roof: The car roof must be illuminated at 5 lux intensity for one hour by the emergency light. The car roof should have an anti-slip working surface. These are new requirements with respect to IS 14665.

3) Pit access door mandatory: For pits up to 2.5 m in depth, access by the ladder is permissible. In case there is no access door to the pit other than the landing door, the door lock shall be reachable within a height of 1.8 m and a maximum of 800 mm horizontally from the pit ladder; or, there has to be a permanently installed device that will allow a person in the pit to unlock the door. IS 14665 does not cover this requirement.

4) Control station in the pit: To prevent technicians needing to use ladders or stools to reach components underneath the lift car, e.g., to facilitate inspection or maintenance, a control station with a stop button is mandatory in the pit. In addition, an audio signaling device must be located in the pit near the refuge spaces for use in case of entrapment.

A reset function to bring the lift in the normal operation must be located outside of the lift shaft. All these requirements are additional to the existing requirements as per IS 14665. 

5) Safety gear for counterweight: A safety gear shall be fitted to the counterweight where there is an accessible space under the pit (such as a storage space or car park). A solid pier under the buffers extending to the solid ground as permitted in IS 14665 will no longer be permitted. 

6) Car roof balustrades: Balustrades shall be provided on the lift car roof. They shall have the specified strength and height requirements. These requirements have been introduced to reduce the risk of maintenance persons falling into the shaft while working on the car roof. The new requirements are as follows:

• Where the distance between the inner edge of the balustrade handrail and the shaft wall is up to 500 mm, the balustrade must have a minimum height of 700 mm.

• Where the distance between the inner edge of the balustrade handrail and the shaft wall exceeds 500 mm, the balustrade must have a minimum height of 1100 mm.

7) Car roof and pit refuge spaces: The minimum volume requirements for the safety refuge spaces on the car roof and in the pit have been specified as follows:

• Upright position: 0.4 x 0.5 m (horizontal dimensions), 2 m (height)

• Crouching position: 0.5 x 0.7 m (horizontal dimensions), 1 m (height)

• Laying position: 0.7 x 1.0 m (horizontal dimensions), 0.5 m (height) for pit only

The revision document requires that the landing door providing access to the pit must be able to be opened from the shaft so that maintenance persons can exit the lift shaft even if the relevant landing door is closed. These are improvements over the provisions of IS 14665.

8) Protection for sheaves and pulleys: The revision document based on ISO 8100-1 requires nip guards to prevent introduction of objects between the ropes and pulleys. It also specifies, elaborately, the requirements for guards used to protect the rotating parts, as well as devices for preventing the ropes from leaving the grooves of the pulleys. IS 14665 has very limited requirements toward these issues.

9) Bypassing of car/landing door contacts: For facilitating maintenance of contacts of landing door, car door and door locking, the revision document based on ISO 8100-1 allows bypassing of either the car-door-closed contact or the landing door contacts (not both together) in the inspection operation or emergency electrical operation from the control panel or emergency/test panel. A separate monitoring signal is required to prove that the car door is closed before movement with bypassed car-door-closed contacts. In case of manually operated landing doors, it shall not be possible to bypass the contacts of landing doors and the landing-door locks at the same time. These provisions, which facilitate maintenance of high-rise lifts, are not covered in IS 14665.

Changes Affecting the Building Design

The revision document based on the ISO 8100-1 standard introduces some changes to the requirements that the building designer must fulfill. These changes apply to the lift shaft and are as follows:

Laminated glass: All glass used in the lift shaft must be laminated. IS 14665 stipulates that glass panels placed at points normally accessible to persons shall be made of laminated glass.

Stronger shaft walls: Shaft walls to withstand 1000 N, as against 300 N required as per IS 14665.

Shaft ventilation: As per the revision document based on ISO 8100-1, shaft ventilation is the responsibility of the building designer. The lift manufacturer must provide all the necessary information; for example, the heat emissions of the lift components, permissible maximum temperature in the lift shaft, etc. This approach facilitates energy-efficient building design where ventilation requirements are determined based on the most energy-efficient solution, while at the same time taking into account the working conditions for the maintenance persons working in the lift shaft, and the comfort of the passengers inside the car.

Fire extinguisher: A fire extinguisher can be located in the shaft. Activation of the sprinkler shall only be possible when the lift is stationary at a landing and the main switches of the lift and lighting circuits are automatically switched off by the fire or smoke detection system.

Improvements in the Product for Safe Working 

The adoption of the revision document based on ISO 8100-1 will permit the latest technology of PESSRAL to be used in the lift controls.

PESSRAL is the acronym for “Programmable Electronic Systems in Safety-Related Applications for Lifts.” Programmable electronics in control and safety systems is expected to increase the reliability and reduce production and maintenance costs. Today, safety-related programmable electronics are used in many sectors, including the machinery, automotive and process industries. PESSRAL in the lift controls could be used to detect UCM. Other issues that could be handled through PESSRAL include multiple inspection control stations, monitoring of the bridged door switches, car and landing door bypassing functionality, etc.

The adoption of the revision document based on ISO 8100-2 will bring in the following two new and important aspects to lifts/lift components.

Type testing mandatory: The lift safety components will have to be type tested (by an accredited laboratory).

The following safety components will need type testing to be done:

i) Landing and car door locking devices

ii) Safety gear

iii) Overspeed governor

iv) Buffers

v) PESSRAL

vi) Ascending car overspeed protection means

vii) UCM protection means

viii) Rupture valve/one-way restrictor

2) Design Calculations: Important calculations, e.g., machine traction calculations, guide rail calculations, suspension rope safety factor, etc., are elaborated.

The following calculations will be available for use:

i) Guide rail

ii) Evaluation of traction

iii) Evaluation of safety factor on suspension ropes

iv) Ram, cylinder, rigid pipes and fittings

v) Calculations against over pressure

vi) Calculations of jacks against buckling

In addition, landing doors must be subjected to pendulum shock tests: hard and soft pendulum/soft pendulum, depending on the construction of the doors with/without glass.

Exclusions: The current Indian Standards on lifts are “codes of practices.” Thus, for example, IS 14665 Part 1 is devoted to the outline dimensions of lifts; Part 2 contains the basics of the traffic analysis. However, the revision documents are based on ISO 8100-1 and ISO 8100-2, which are essentially safety standards and, hence, do not have this information. The users may refer to the revised National Building Code of India-2016 (Part 8/Section 5A), which contains in-depth, updated and comprehensive information on such topics.

Changes in the Revision Documents With Respect to the ISO 8100-1 and ISO 8100-2

It would be interesting to note that the revision documents are not identical to ISO 8100-1 and ISO 8100-2. There are some changes proposed in the ISO documents to suit Indian conditions; the major ones are listed hereunder:

1. The title of the document has been changed from: Lifts for the transport of persons and goods — Part 1: Passenger and goods passenger lifts to Lifts for the transport of persons and goods — Part 1: Passenger and goods lifts, to align it with the current practices in India.
2. In general, all references to the EN standards have been deleted and substituted by equivalent IS/IEC/ISO standards.
3. Optional provision of “adjacent car rescue” via emergency doors fitted to the side walls of the adjacent cars is deleted.
4. Optional provision of emergency trap door fitted to the lift car roof is deleted.
5. The provision of partitions in case of the lift well containing multiple lifts is made more stringent, aligning it with the existing Indian Standards. The partitions are required for full height of the well irrespective of the distance between moving parts of the lifts.
6. Safety requirements have been added in the revision document when the machinery is placed inside the well and is to be maintained from a platform positioned in the path of the counterweight or balancing weight. This is in addition to that as specified in ISO 8100-1 with respect to the platform being in the travel path of the car.
7. Reference to hinged car doors is deleted, as such doors are not in use in India.
8. Minimum width of the entrance is specified as 700 mm in the revision document, aligning it with IS 14665.
9. In case of vertically sliding doors, a safety condition is added that provision shall be made such that in case of the failure of one suspension means of the panel, the panel shall not fall. 
10. Requirements have been enhanced in case additional building doors are to be installed in front of the landing door. Requirements of minimum space between the two sets of the doors, means of communication and proper ventilation have been specified in the revision document.
11. The existing condition as per IS 14665 that power-operated doors shall not be provided with the vision panel is maintained in the revision document.
12. Requirement for permitting locking only one door panel in case of indirectly mechanically linked panels has been made more stringent by adding the condition that the single locking shall prevent the opening of the other panels notwithstanding breakage of the panel linking member, thus aligning it to the existing IS 14665.
13. The standard weight of a person has been retained as 68 kg as per the existing IS 14665, as against 75 kg as per ISO 8100-1. The relationships of the maximum permissible car area versus the rated capacity in kg, as well as the minimum required car area versus the carrying capacity in terms of number of passengers, are also maintained as per the existing IS 14665.
14. ISO 8100-1 permits bigger car area in case of goods passenger lifts hydraulically driven; however, the same is not permissible in case of goods passenger lifts with traction drive. The revision document, on the other hand, does not differentiate between the permissible car areas in case of goods lifts on the basis of the drive type. The revision document allows a bigger car area in case of goods lifts as per the existing IS 14665.
15. ISO 8100-1 does not treat motor vehicle lifts separately. The revision document specifies the minimum load rating for such lifts as 1.42 kN/m².
16. The emergency light level in the car has been increased from 5 lux as per the ISO 8100-1 to 20 lux in the revision document.
17. The revision document adds specifications for non-metallic filler weights for counterweight, aligning it with IS 14665.
18. ISO 8100-1 does not recognize alternative elastomeric-coated suspension means, such as coated steel belts (CSB). The revision document permits CSBs as a suspension means. CSBs are fully specified in the revision document, aligning with existing IS 14665 and IS 15785.
19. On the other hand, the revision document does not permit chains as a means of suspension in line with IS 14665, though ISO 8100-1 permits the same.
20. The minimum number of ropes in the case of car suspension in the revision document is related to the diameter of the rope. Thus, the minimum number of ropes as per the revision document and existing IS 14665 is four for 8-mm-diameter rope and three for 10-mm-diameter and bigger ropes. ISO 8100-1, on the other hand, permits two rope suspensions. The revision document, however, permits use of two CSBs, subject to monitoring.
21. The coupling of the motor with the component on which the brake is fixed by belts is permitted by ISO 8100-1. This is not permissible, however, as per the revision document. The revision document further prohibits connecting main drive gear to the traction sheave by friction gearing, belt, chain, clutch, etc.
22. Provision of Automatic Rescue Device (ARD) is mandatory as per the revision document, whereas ISO 8100-1 has no such provision. The functionality of ARD has been completely defined in the revision document.
23. The revision document specifies the requirements for Normal Slow-Down devices, Normal Terminal Switches as per the existing IS 14665, in addition to the Final Terminal Switches. ISO 8100-1 specifies only the Final Terminal Switches.
24. The revision document specifies the fire protection requirements of the lifts in cases of buildings taller than 15 m, and includes the Fire Lifts requirements.
25. The revision document has incorporated the correct formulae, totaling 6 nos., in place of the incorrect ones as per ISO 8100-2.

Thus, it may be observed that the revision documents propose to enhance the safety levels beyond that as per ISO 8100-1 and ISO 8100-2, without compromising it anywhere.

Conclusions

The above discussed improvements will go a long way in enhancing the safety of persons using or maintaining lifts. Of course, the maintenance of lifts is very important, and keeping lifts in safe working condition is only possible through a well-planned and executed maintenance program. However, only a safe-designed and properly installed lift can operate in safe conditions with good maintenance. 

There are several other related Indian Standards that have been published by the BIS fairly recently and have been listed in the Annexure 2 for ready reference. Similarly, there are several new Indian standards under development, which also have been listed in the Annexure 3 for ready reference for those interested. Future plan of work is to study other related international standards for possible adoption by the BIS. The list of such standards is as given in the Annexure 4.

Disclaimer: The above article is written in good faith to educate and make people aware of the proposed changes to the Indian Standards on lifts. The stated changes to the standards are proposals only, unless the same are published by the Bureau of Indian Standards. Also, the changes described here are of the nature of bird’s eye view and do not contain all the information/conditions in depth for which users are advised to refer to the original texts. This article with similar text was also published in IEEMA Journal in April 2021.

Further, the views expressed are personal to the authors. The authors/publisher or the organizations where the author may be employed shall not be held responsible for any action taken by anybody based on the information contained in the article.

Editor’s note: The aforementioned Annexures will be published in ELEVATOR WORLD India, 1st Quarter 2022 issue. All pictures in the article are courtesy Otis Elevator Company (India) Ltd.

Read: Revision of the Indian Standards on Passenger and Goods Lifts, Part 2

Pravin Tipnis

Pravin Tipnis holds a degree in mechanical engineering from Veermata Jijabai Technological Institute, Mumbai, as well as a post-graduate degree from Indian Institute of Technology, Bombay, and has experience of more than 36 years in the vertical-transportation (VT) industry. This includes 19 years at Olympus Elevators in the technical/product development areas, which he headed, and, subsequently, 10 years at KONE, where he was responsible for various large infrastructure projects, such as metros, airports, etc.; and high-rise buildings. An active post-retirement VT consultant offering his services to various small and big, Indian and multinational companies, Tipnis specializes in technical training, code training and product/components consultancy. He is an active member in code committees of Elevators, Escalators, and Moving Walks “ETD 25,” as well as the National Building Code of India “CED 46” for several decades. Currently, he is the convener of the Working Group Panel P4 of the ETD 25 committee. His relevant publications include “Occupant Evacuation Lifts: Fire India 2019 Conference” and “Elevator Car Ventilation Design to Mitigate the Risk of Spread of COVID 19: Research Square.”