Information Bulletin: Equipment Exposed to the Weather - MRL Control Spaces

1. General details

This bulletin provides clarity to the code requirements for elevators being installed with equipment exposed to the weather. With the increased prevalence of Machine-Room-Less (MRL) elevators, some have been installed with a control space located on an outdoor landing, creating hazards related to accessing and servicing the exposed equipment.

When rescue operations must be performed through a control cabinet located on an outdoor landing, protection of the worker performing the rescue operation must be considered in all weather conditions.

2. Regulatory requirements

ASME A17.1-2016/CSA B44:16 provides the requirements for the installation of equipment exposed to the weather.

CSA C22.1:18 provides the requirements for electrical equipment enclosures that may be subject to drops of falling liquid and CSA C22.2 NO. 94.2:20 provides additional construction and performance requirements for enclosures with environmental considerations.

When an MRL elevator has a control space that is located on an outdoor landing, that control cabinet is required to meet the enclosure requirements of CSA C22.1:18 and CSA C22.2 NO. 94.2:20

CSA B44:16

2.7.6.6 Equipment exposed to the weather
Machines, control equipment, sheaves, and other machinery shall not be exposed to the weather unless they are suitable for the application.

2.7.2.2 Maintenance path in machinery spaces and control spaces
All components requiring maintenance in machinery spaces and control spaces shall have safe and convenient access.

Note:  Elevator Industry Field Employees’ Handbook – Sec.5.1(g) “Never troubleshoot circuits when standing or kneeling on metal, wet surfaces or in water…”

CSA C22.1:18

2-400 Enclosures, type designations, and use
(c) Type 3R for use outdoors;
(d) Type 4 for use where the enclosure may be subject to direct streams of water;

22-002 Category definitions
Locations covered in this Section shall be classified as follows:
1.   Category 1 — the location is one in which moisture in the form of vapour or liquid is present in quantities that are liable to interfere with the normal operation of electrical equipment, whether the moisture is caused by condensation, the dripping or splashing of liquid, or otherwise;

22-100 Essential equipment only
(1) Only electrical equipment that is essential for the processes being carried on in a room or section of a building shall be installed in Category 1 and Category 2 locations.

22-102 Type of construction
(4) Where the electrical equipment is, or is likely to be, exposed to splashing of water, it shall be of a weatherproof or watertight type of construction.
(5) Where the electrical equipment is, or is likely to be, exposed only to the falling or condensing of moisture, it shall be of a drip-proof, weatherproof, or watertight type of construction.

3. Installation requirements

Any machine, control equipment, sheave or other machinery exposed to weather, including control cabinets that open onto landings exposed to weather, must be suitable for the application. When a control space is exposed to weather, a safe and convenient maintenance path must be maintained at all times.

When an MRL elevator designed to have a control space located on one of its landings is being installed in a hoistway with outdoor landings, section 22 of CSA C22.1:18 needs to be considered in the design. Clause 22-100 states only essential equipment may be located in a Category 1 location. If the control space can be located on a landing other than a Category 1 location, it must not be located in a Category 1 location.

When an MRL elevator has a control space located on an outdoor landing, it is considered a Category 1 location and clauses 2-400 and 22-102 of CSA C22.1:18 apply. Clause 2-400 requires either a type 3R or type 4 enclosure.

When a control space must be located on an outdoor landing due to design constraints, it is possible to schedule maintenance and repairs around adverse weather conditions to mitigate hazards. As rescue operations cannot be postponed due to weather, when a rescue operation is performed from an outdoor landing, protection for the rescue operations worker (including safe and convenient access), as well as any exposed equipment, must be maintained.

Nav Chahal, Manager, Transportation
 

References:
CSA B44-16
CEC 22.1-18
Elevator Industry Field Employees’ Handbook
Safety Standards Act
Electrical Safety Regulation
Elevating Devices Safety Regulation