by Richard McPartland
Two new European standards for the design and manufacture of lifts were introduced in August 2014 - EN 81-20: 2014 and EN 81-50: 2014.
- EN 81-20: 2014 sets out safety requirements for construction and installation.
- EN 81-50: 2014 sets out test and examination requirements for certain lift components.
The standards replace the EN 81-1 and EN 81-2 standards that were introduced in 1998 and apply to all lifts taken into use from 1 September 2017.
(Please note that it had been planned to withdraw BS EN 81-2 on 31 August 2017 but at the time of writing this has not yet happened - we will update this article in due course).
The new standards aim to improve accessibility, safety and comfort, lift passengers and those required to service installations. The standards also make stipulations in terms of building design and interface.
Both standards are regulated by the European Committee for Standardisation (CEN).
What do the regulations mean for passenger safety?
The standards contain a number of requirements with the aim of improving passenger safety. These include:
Movement and speed
- Required protection against the risk of an ascending lift car over speeding has now been extended to cover rescue situations.
- Enhanced requirements have been stipulated in relation to the protection mechanism to mitigate the risk of the lift car moving away from the landing.
Door detection systems
- A non-contact detection system designed to prevent doors closing if an obstruction is detected (a 'curtain of light') is required to reduce the risk of doors making contact with passengers entering or exiting the lift car. Mechanisms based on photocell technologies will not be compliant with the new requirements.
Car door locking mechanism
- To prevent trapped passengers falling into the lift shaft when attempting escape from a stopped lift car a mechanism is required to prevent car doors being opened from inside when the car is outside the unlocking zone (in line with the landing doors).
Fire classification for lift car materials
- Materials used for car floors, walls and ceilings have been updated and must now meet fire classification requirements stipulated in EN 13501-1. Minimum classifications are:
- Ceilings: C, s2 and d0
- Floors: Cfl, s2
- Walls, C, s2, d1
Here C and Cfl refer to 'reaction to fire' classification and s and d refer to the classification of materials with regard to smoke and formation of flaming droplets and particles respectively)
- Car and landing doors and car walls must now meet updated strength requirements. Doors must include retainers to keep the door panels in place if the guiding elements malfunction.
- Car and landing doors must be able to withstand impact force equivalent to a person colliding with the door at running speed. Car walls must be able to withstand the equivalent force to a person pushing against them.
- Lift walls (including those made of glass) must withstand shock to ensure the integrity of the structure (a rigid pendulum with 0.5m drop height must withstand a 10kg shock, a soft pendulum with 0.7m drop height must withstand a shock of 45kg).
- The standard requires higher lighting levels in both the lift car and shaft. In car lighting should provide illumination of 100 lux (was 50 lux) with emergency illumination of 5 lux for one hour (was 1W for one hour). Lighting should be placed at a height of 1m in the centre of the car close to emergency push buttons.
- The lift car roof safety hatch should be 0.4m x 0.5, with the toe guard able to withstand 300N without permanent deformation of 1mm and elastic demormation of 35mm (minimum).
The standards aim to improve accessibility and safety both for lift passengers and those required to service installations.
What do the regulations mean for technician safety?
Shaft lighting, car roof lighting, machine room lighting
- Shaft lighting should provide a minimum of 50 lux a metre above the car roof vertically, 1 meter above the pit floor everywhere a person can stand, work or move between work areas, and 20 lux elsewhere excluding any shadows.
- Emergency lighting on the car roof must now be sustained at 5 lux for one hour. The car roof itself should also have an anti-slip working surface.
- The machine room should have a lighting of a minimum 200 lux.
Control station location and access to pit and machine room
- Access requirements for pits deeper than 2.5 metres are now stricter with designated dimension, strength and location requirements for access aids (such as ladders). An access door might also be required.
- To prevent technicians needing to use ladders or stools to reach components underneath the lift car a control station (including audio communication), in case of entrapment, must now be located in the pit near the refuge spaces. A reset function must be located outside of the lift shaft.
- Safety gear should be fitted to counterweights where there are accessible spaces under the pit (such as a storage space or car park).
Access, inspection and rescue doors
- Access/inspection doors should be provided (rather than inspection trapdoors) to allow safe access for technicians.
- Machine room shaft access doors should be a minimum of 2m (h) and 0.6m (w).
- Pulley-room access doors should be a minimum of 1.4m (h) and 0.6m (w).
- Access trapdoors (to machine and pulley rooms) must be counterbalanced and provide clear passage of 0.8 x 0.8m
- Emergency doors should be a minimum of 1.8m (h) x 0.5 (m).
- Inspection doors should be a minimum 0.5m (h) x 0.5 (w).
Lift car roof balustrades
- There are now defined strength and height requirements for balustrades on the lift car roof to prevent those working here falling into the lift shaft. Such balustrades:
- Where the distance between the inner edge of the handrail and wall of the lift shaft is up to 500mm the balustrade must have a minimum height of 700mm.
- Where the distance between the inner edge of the handrail and the wall of the lift shaft exceeds 500mm the balustrade must have a minimum height of 1100mm.
Horizontal projections into the shaft
- Any ledge or similar that protrudes into the shaft or horizontal beam greater than 150mm wide must be protected to prevent a person standing on it. The exception to this rule is a car roof where access is prevented by a balustrade. This exemption does not apply for ledges around the pit such as those that might be found in a partially-enclosed elevator shaft and car roof ballustrades.
Safety refuge spaces
- Volumes for safety refuge spaces have been increased to 0.4 x 0.5m (horizontal) and 2m (height) in the upright position, 0.5 x 0.7m (horizonal) and 1m (height) in the crouching position and 0.7 x 1m (horizontal) x 0.5m in the laying position (pit only).
- The landing door to the pit must be able to be opened from within the shaft allowing technicians to exit even if the landing door is closed.
- A RCD device should be provided for seperate 230v circuits and LED lighting. A shaft switch will need to be installed to guarantee an inspection speed of 0.3 m/s.
What changes need to be considered when designing buildings?
EN 81-20:2014 introduces a number of changes to requirements as they apply to the lift shaft. Specifically:
- All glass must be laminated.
- Shaft walls must be able to withstand 1000 N.
- The shaft should now contain a fire extinguisher though the sprinkler should only be activated when the lift is stood still at a landing.
- The fire or smoke detection system should switch off the lift's main switches and lighting circuits when activated.
- Installations in buildings taller than 40m (in which the ride distance exceeds 40m) must account for building shrinkage in building design.
- Responsibility for ventilation of the shaft now falls to the building designer. Manufacturers must provide key information on lift components (such as heat emissions). This approach allows designers to consider energy efficient solutions while mindful of working conditions for technicians and passenger comfort.
Where can I find more information?
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