Door Open Time – Hold the Door!

Door open time allows the passenger to enter or exit the elevator with enough time as not to unnecessarily hurry and to avoid contact with the closing doors. In large buildings with many elevators sharing the same lobby area, it's common for one or two sets of hall call stations to be located a considerable distance from some of the elevators. In that design, often passengers find themselves at the furthest away point from the available elevator and it seems the more you have to carry the farther that is!
Even for single elevator locations with one hall call station in a relatively small lobby, if the door open time is not sufficient you may experience the same problem.
The good news is; it all avoidable and should be easily fixed if there is a problem. Even if the door timing is within the equipments design and meets code parameters, the door times can usually be adjusted readily to meet the needs of the passengers. Elevator systems are configured with door timers that are adjustable and some deteriorate with age and use that is often affected by environmental conditions, poor maintenance, and mal-adjustment. Older systems use relay timers, resistor-capacitor timers (RC circuits) and early solid-state timers. All are subject to age limitations and usage failures. Newer systems implement programmable IC circuits and timers that hold their settings without gradual deterioration, and are very easily changed as needed. Some offer different door times for the same elevator depending on floor location; for instance the lobby may be afforded a greater door open time to allow more time for a greater number of passengers to access the elevator, while other landings may not require the additional time due to less traffic. These systems can be programmed by the service provider should demands change.
The older systems can also be changed by replacing worn or faulty components and times changed by altering the value of the timer components. For instance should more door open time be desired on a system controlled by RC circuitry; by changing the value of either the resistor or capacitor, the change is complete. Same with adjustable timers; by changing the resistor or other timer features, the time is altered.
In other cases a programmable timer may replace an older type and offer a much greater range of adjustments and not be cost prohibitive. Your service provider will be able (or should be able) to offer you options for keeping the door open time current to meet your needs.
Americans with Disabilities Act (ADA) has a minimum door open time required. The formula to calculate that minimum door time is: "The minimum acceptable time from notification that a car is answering a call until the door starts to close shall be calculated by the following equation, but shall not be less than 5 seconds":
T = D/1.5 ft/s (D/455 mm/s)
T = total time in seconds and D = distance in feet (millimeters) from the point in the lobby or corridor 60 inches (1525mm) directly in front of the farthest call button controlling that car to the centerline of its hoistway door. T begins when the signal is visible from the point 60 inches (1525mm) directly in front of the farthest hall call button and the audible signal is sounded.
Remember, a five (5) second minimum is required regardless of the physical setup of hall calls, signals, and elevators in your building for hall calls - not car calls registered in the elevator. We bring this point out because we have been often questioned about elevators having less than the minimum 5 seconds when seemingly responding to hall calls but were actually responding to car calls that have a lesser value on open door times. A passenger may be waiting in the elevator lobby, let's say on the third floor of a five landing building, and had placed a down hall call; the elevator stops, doors open and a passenger exits and the doors close in quick order before the hall passenger can access the car. Why? Well the elevator was continuing in the up direction to serve those upper floors and is not responding to the down hall call, but has delivered a passenger to the third floor. Hall passenger sees elevator action, assumes it for their demand, and reacts accordingly. This scenario is not rare; we've noted it often while performing traffic studies for performance evaluations and code compliance.
We will look at car call door times: ADA requires three (3) seconds of fully open door time in response to car calls. Fully open is taken to mean by us as when the door panels open to or clear the door returns or jambs and clear opening access is granted. Time begins at that point and ceases when the door panel(s) extend into the clear opening area. Do not take into consideration visual and audible signals for car call response door times.
The good news is that these times are adjustable and the 5 & 3 second respectively for hall and car demands are minimums; you can exceed those times as needed to provide for comfort and ease of use for your passengers.

We stand prepared to assist.