Frequently Asked Questions


Understanding the factors that drive 9-1-1 response
For most of us throughout the United States, dialing 9-1-1 to report an emergency is a deeply ingrained reaction. Since our founding in 1987, Denco 9-1-1 has worked diligently to provide the technologies, systems, training courses, and community outreach to support a swift and predictable response during some of life’s most unpredictable events. These FAQs address some of the most common issues affecting callers, telecommunicators, and emergency responders.

+ When should I call 9-1-1?

Don’t hesitate to dial 9-1-1 anytime you encounter a life-threatening situation, or an event in which police, fire or emergency medical help is needed right away. These include, but are not limited to, fires, crimes in progress, serious car accidents with injuries, heart attack or stroke symptoms, abductions, and suspicious activity. If you are unsure of whether your situation is an emergency, go ahead and dial 9-1-1. The 9-1-1 call taker can determine if you need emergency assistance.

+ When should I avoid calling 9-1-1?

If there is no need for immediate assistance by police, fire or medical personnel, please call the proper seven-digit telephone number found in the phone book or through directory assistance. Please do NOT dial 9-1-1 for general information, minor accidents without injuries, barking dogs, power outages, keys locked in a vehicle, or as a prank.

+ Will you be able to find me if I call from a cell phone?

Today, the majority of 9-1-1 calls are placed from mobile phones, which require a different approach to location and mapping than traditional landline phones. In response to this significant trend, we’ve equipped each of the 9-1-1 answering points in our district with advanced call processing software and digital mapping technology. The equipment is capable of receiving and displaying wireless location data, including the wireless phone number and the caller’s approximate location on a map. Since location information is approximate, it remains critical for callers to provide as much location information as possible.

+ If I’m unable to speak, should I still dial 9-1-1 for emergencies?

Even if you’re unable to speak due to a medical condition or dangerous circumstances, 9-1-1 can still be a vital lifeline. Remain calm, dial 9-1-1, and simply leave the phone off the hook. If safe, attempt to make some sort of noise such as tapping the phone or clapping your hands to let the dispatcher know there is an emergency. With enhanced 9-1-1 from a landline phone, 9-1-1 will have your address — and with advanced call processing and digital mapping in use by Denco 9-1-1, telecommunicators will have your approximate location when you call from a wireless device.

+ Are there special instructions for hearing-impaired callers who dial 9-1-1?

Callers who communicate using a teletypewriter or telecommunications device for the deaf, known by the acronyms TTY and TDD, have equal access to 9-1-1 services. In an emergency, hearing-impaired callers should dial 9-1-1 and connect to TTY, then tap a few TTY keys. Although this is not required, this activates the 9-1-1 telecommunicator’s TTY immediately. Once the telecommunicator answers, state what kind of help is needed, respond to all questions, and stay at your TTY if safe until the call is completed. We are currently working with equipment and service providers to enable integrated text-to-9-1-1 capabilities to all 11 PSAPs. Initial testing will begin by January 2016.

+ How do 9-1-1 operators effectively communicate with non-English speakers?

When a non-English speaking caller uses 9-1-1, the telecommunicator has the ability to add on an interpreter service, which offers translations in more than 140 languages. In these instances, the caller may hear a short conversation in English and some clicking sounds as an interpreter is added to the 9-1-1 call.

+ What steps can I take to be proactive if I ever need to call 9-1-1?

Keep your phone within reach, make sure your address is easily seen from the street, and post your address and phone number near each phone or on the refrigerator so that visitors, babysitters, and others will have this critical information readily available. Do NOT program 9-1-1 into speed dial, as it’s far too easy to call by accident. It’s also important to be aware of the advantages or restrictions that some types of phones may have. Check with your mobile carrier or VoIP provider for any special instructions related to 9-1-1 emergency calls.

+ What should I do if I dial 9-1-1 by mistake?

Do not hang up! Stay on the line and tell the telecommunicator that you have misdialed. If you hang up before talking to a telecommunicator, the call will still be delivered to the 9-1-1 center. Valuable time may be lost for other callers while the telecommunicator is trying to verify that there is no emergency at your location.

+ What do I need to know to give a good description of people or vehicles involved in a 9-1-1 call?

When describing people, start at the head and work your way down. What is their race and sex? How tall are they? What color is their hair? What are they wearing? Do they have a mustache, beard, glasses, walk with a limp, or have anything else about them that might make them stand out?

When describing a vehicle, take note of the color, make and model, body style, license plate (number and state), and any additional identifying characteristics such as bumper stickers, window decals or body damage.

+ How reliable is the location data used to dispatch responders?

Denco 9-1-1 uses geographic information system mapping and other technologies to continually update and verify location accuracy. As a result, our data is highly accurate — which helps responders get to the scene of an emergency as quickly as possible.

+ Why would 9-1-1 operators need to ask for my phone number and address? Doesn’t this information pop up when I call?

For calls from landline telephones, our enhanced 9-1-1 system automatically provides telecommunicators with the address and phone number you’re dialing from. But for most mobile phones, we may only receive an approximate location — and for many Voice over Internet Protocol (VoIP) phones, we may receive outdated information or none at all. Verifying your location and contact information are of the utmost importance, which is why our telecommunicators will ask you to provide or confirm this information.

+ How does 9-1-1 service on VoIP devices differ from landlines and mobile phones?

Voice over internet protocol, also known as Internet, digital, broadband or cable phone service, is a rapidly growing alternative to traditional phone service. VoIP may look and appear to work like a traditional phone, but it connects through the Internet instead of a telephone line. As a result, VoIP has potential limitations with respect to 9-1-1 access. You should always contact your VoIP provider to verify that you can access 9-1-1 with your phone, and register your address accurately. Be sure to keep your location current with your VoIP provider, especially if you move. When dialing 9-1-1, give your location and callback number. You should also be aware that if your power goes out, your VoIP service may be out as well. When traveling with your VoIP adapter, your call may not reach the correct 9-1-1 center; use another phone instead.

+ Where are 9-1-1 calls answered?

9-1-1 calls are sent to the public safety answering point that is responsible for dispatching help based on the location of the caller. Across the Denco 9-1-1 service area, these answering points are located at the Denton County Sheriff’s Office and the police departments of Carrollton, Denton, Flower Mound, Highland Village, Lake Dallas, Lewisville, Roanoke, The Colony, the University of North Texas, and Texas Woman’s University.

+ What technologies and systems come into play when I dial 9-1-1?

Denco 9-1-1 is constantly assessing and refining our operations to keep up with changing technologies and evolving user needs. We were the first in Texas to implement technologies that deliver 9-1-1 location information for cell phones, and we were the first to migrate to a Next Generation 9-1-1 router — a critical step in providing the Internet protocol-based infrastructure required to support future emergency communication requests. In addition, we use advanced geographic information systems to maintain up-to-date mapping displays.

Public safety answering points

On any given day, telecommunicators within the Denco 9-1-1 service area field more than 900 calls for help. When a caller dials 9-1-1, the call is routed to one of 11 state-of-the-art communication centers. These public safety answering points, or PSAPs, act as the first point of contact for people reporting fires, crimes, injuries, and other emergencies.