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Public Safety

What is Enhanced 911 calling?

Enhanced 9-1-1 (also called E 9-1-1) is a federally-mandated program that seeks to improve the effectiveness and reliability of local emergency services by providing emergency dispatchers with valuable information when a 9-1-1 call is received by the Public Service Answering Point (PSAP).

Why is Enhanced 911 important?

Wireless phones are important to members of the public when they want to call 9-1-1. Wireless calls to 9-1-1 account for more than 80% of all emergency 9-1-1 calls made in the United States. There are more than 600,000 wireless 9-1-1 calls made every day in the U.S. That number is constantly growing as more people use their wireless phones to call for emergency help, to save lives and to help fight crime.

T-Mobile’s fact sheet about Personal & Public Safety provides more details about how we partner with local jurisdictions to make sure that Enhanced 9-1-1 calling meets all United States government requirements.

Who is responsible for making sure that mobile 911 calls get connected and stay connected?

Enhanced 9-1-1 is regulated by the FCC and initiated by jurisdictional request. There is close coordination between the jurisdiction and T-Mobile to make sure that the most up-to-date features are provided to the local Public Safety Answering Point (PSAP).

The deployment of E9-1-1 requires upgrades to local 9-1-1 PSAPs) plus coordination among public safety agencies, wireless carriers, technology vendors, equipment manufacturers, and local wireline carriers.

Health Facts

Is the general public being exposed to radio waves that exceed the government’s allowable limits?

Antennas on cell sites are designed so that the vast majority of the RF energy emitted from the antennas is directed outward from the source. Most macro site antennas are mounted on monopoles or on building facades & rooftops – usually at 50’ to 150’ above ground level. This, and the fact that radio waves generally dissipate over distance, means the general public experiences significantly lower levels of allowable limits than required by the Federal Communications Commission.

Street-level measurements of RF emissions are typically 150 times — and more — below the FCC limit. As the FCC explains, “Measurements made near typical cellular and PCS cell sites have shown that ground-level power densities are well below the exposure limits recommended by RF/microwave safety standards used by the FCC.” FCC RF Exposure Guidelines

According to the FCC: “While it is theoretically possible for cell sites to radiate at very high power levels, the maximum power radiated in any direction usually does not exceed 500 watts.” According to the FCC

There are internet studies that say there are health risks associated with wireless antennas—how do you explain that?

There is certainly a lot of information – and misinformation – available today on this topic and it can be difficult to review and interpret it. Although there are isolated studies that suggest facilities may pose a health risk, the safety limits adopted by the FCC are “based on the recommendations of expert organizations and endorsed by agencies of the Federal Government responsible for health and safety. Therefore, there is no reason to believe that such towers could constitute a potential health hazard to nearby residents or students.”

The studies that we rely on are considered statistically sound and are accepted by the scientific community worldwide. T-Mobile can provide reputable third-party and independent sources who have conducted studies. Some of them are:

  • The American National Standards Institute (ANSI)
  • The Institute of Electrical and Electronics Engineers (IEEE)
  • The Federal Communications Commission (FCC)
  • The American Cancer Society
  • The World Health Organization

FCC Questions & Answers

Are electromagnetic fields (EMF) harmful or dangerous?

According to the World Health Organization, “Electromagnetic fields are present everywhere in our environment but are invisible to the human eye. Electric fields are produced by the local build-up of electric charges in the atmosphere associated with thunderstorms. The earth’s magnetic field causes a compass needle to orient in a North-South direction and is used by birds and fish for navigation.”

What WHO says about EMF

Property values and site aesthetics

Will a wireless antenna facility near my residence affect the value of my property?

Experts in the field of real estate report that the availability of cell service is an important feature to current home buyers. Michael Estrin of Bankrate.com noted, “Today, (home) buyers want to know about the home’s technology. They want to hear about cell service and Internet, not cable and telephone.”

The City of Portland, Oregon added, “The argument that property values are affected by wireless sites (positively or negatively) has very little documentation other than anecdotal sources. City staff is aware of arguments on both sides of this issue.”

Can T-Mobile camouflage cell sites to blend in with surrounding topography?


T-Mobile works hard to build the least obtrusive, most technically feasible sites to provide reliable service. When we modernize or upgrade sites, most often we do not change the structure, but instead replace antennas and radio equipment with updated technologies. When we build a new wireless facility, we look to existing structures (e.g. industrial, commercial, and municipal buildings and structures) before resorting to a new freestanding facility. We also place a priority on sharing space on an existing carrier’s facility before considering building a new one. Better wireless coverage often requires antennas be mounted on structures that are taller than most of the surrounding structures in an area. Stronger, more reliable communications require an unobstructed line-of-sight between a customer’s phone and the cell site. We always work with each community to make cell sites as unobtrusive as possible while still meeting service goals.

Why does T-Mobile need to build a cell site in my neighborhood?

Our decision to locate a new cell site is based on scientific criteria. In making our decision on where to locate a new site, T-Mobile undertakes a rigorous engineering analysis of available RF signal coverage and future expansion needs.

To choose a potential site, terrain data within the service area is entered into a computer, along with a series of variables, such as proposed antenna height, foliage and building data, population density, available radio frequencies and wireless equipment characteristics. From this information, engineers determine an area for the optimum location and height of the antenna to maximize coverage within the cell.

T-Mobile also looks at different usage patterns of our customers, including the ability to make and hold calls inside buildings and vehicles. Many times a user can make a call on the street, but not be able to make or hold a call as they enter a building. Network data is scientifically measured to determine the amount of traffic at individual cell sites, including the number of dropped and blocked calls. Plus, field technicians, engineers and third-party researchers conduct “drive tests” to collect real-time statistics. These tests simulate the customer experience and provide critical data on signal strength and call clarity.

Local Jurisdiction

The Federal Communications Commission has regulations that spell out local authority parameters related to cell site deployment and upgrades. In a nutshell, what are those rules?

In 2012, Congress enacted the Spectrum Act to help streamline the process for minor modifications to existing wireless facilities. Since then, the FCC has continued to clarify those rules. Basically, if a project qualifies as a non-substantial modification a state or local government must approve the request within 60 days. To read the latest Declaratory ruling, read In the Matter of Implementation of State and Local Governments' Obligation to Approve Certain Wireless Facility Modification Requests Under Section 6409(a) of the Spectrum Act of 2012

When T-Mobile conducts alternative site analyses, why are some potential locations rejected, while others remain in the mix?

T-Mobile performs rigorous research and considers a number of viable sites before selecting the specific location for a new wireless facility. Our site development process includes the following:

  • Radio design engineers develop a “search ring” — a map outlining the geographic boundaries where the new site will ideally be located.
  • Trained personnel conduct an analysis of potential sites for a wireless facility within the search ring and eliminate parcels unsuitable or not zoned for telecommunication facilities.
  • Property owners whose parcels are suitable for a wireless facility and can be zoned to permit this use are contacted to see if they are interested in leasing their property to T-Mobile.
  • A list of potential parcels and landlords are submitted to the radio design engineers, who select the best site option.
T-Mobile believes that conducting alternative site analysis is critical to the municipality and community, especially when siting in residential areas. We are thorough in our analysis of alternative sites and always work to select the site that will provide optimal coverage while minimizing impact.


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