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Free preliminary screen

DAS Necessity Score

A free first look, in less than 72 hours: how likely your building is to need a DAS for emergency radios, a general result for cell phones, and what evidence would settle the question.

Request a DAS Necessity Score

In plain language

What a DAS is.

A distributed antenna system, or DAS, is the antennas, cables and amplifiers installed inside a building to carry radio signal where the outside signal does not reach.

Many jurisdictions adopt fire-code requirements for emergency-responder radio coverage inside buildings. When a building does not provide that coverage on its own, a system is usually required. Codes and local amendments vary, and your authority having jurisdiction decides what applies.

What you send

  • Building address, or city and project location
  • Project stage
  • What needs to work inside: emergency radios, cell phones or both
  • Approximate building size in square feet, if known

No field readings, radio frequencies or plans are needed to make the request. We ask for more only if the review needs it.

Area by area

A first look at one floor.

This is the top floor of a sample building as designed, split into 20 areas the way fire code acceptance tests check each floor. A score estimates which areas are likely to fall short. Then see what the two kinds of change do, for emergency radio and for cell phones.

Illustrative Level 3 plan, the top floor of the sample building: a glass wall with spandrel panels faces a network site to the west; concrete walls with punched windows on the other sides; a concrete core with a stair, an elevator and an electrical room. Signal strength is shown in color under the plan, with a 20-area test grid on top.NETWORK SITEOUR ROOF ASSEMBLY ABOVEOFFICESOPEN OFFICEOPEN OFFICEOFFICESSTAIRELEV.ELEC.GLASS WALL · AS DESIGNEDGLASS WALL · PANEL SWAPSCONCRETE WALL · AS DESIGNEDCONCRETE WALL · AS DESIGNEDCONCRETE WALL · BUILT-IN CHANGESNLEVEL 3 PLANILLUSTRATIVE · NOT TO SCALE

Illustrative wave model, not a predictionLevel 3 plan, top floor. Not to scale.

As designed: most of the floor gets little or no signal. Only the parts of the offices closest to the glass get some signal.

Readings at five spots
  1. West officeLittle or noneLittle or noneFrom DAS
  2. Open officeLittle or noneLittle or noneFrom DAS
  3. StairLittle or noneLittle or noneFrom DAS
  4. East officeLittle or noneLittle or noneFrom DAS
  5. Electrical roomLittle or noneLittle or noneFrom DAS

Readings and grid marks come from the same model as the map.

The DAS Necessity Score is a first look at step 1 for your building: where the building as designed may fall short for emergency radios, with a general read on cell phones.

The result

What you receive, and what it is not.

You receive

  • A preliminary need or risk result for emergency radios
  • A general result for cell phones
  • Predicted good and weak areas, where the information supports it
  • A confidence statement and the inputs used
  • Missing evidence, named
  • The next useful step

It is not

  • A measured test
  • An authority's approval or a guaranteed pass
  • A probability percentage
  • A building-specific result for cell phones, which is paid work
  • A list of building-specific causes or fixes, which is paid work

If the information does not support a score, we tell you what is missing instead of producing one.

Sample layout

What the score looks like.

Each field is filled from your building's information. Fields with no support say so.

Layout for illustration. Field names may change.

DAS Necessity Score Illustrative layout, not a result
Building
Sample commercial building
Scope
Emergency radios, with a general cell-phone result
Emergency radios
Need or risk category
Cell phones
General result
Predicted areas
Shown where supported
Confidence
Stated with reasons
Inputs used
Listed
Missing evidence
Listed
Next step
Stated
Sample buildingProject
ScoreDocument
Radios and phonesScope
IllustrativeStatus

Phones

Cell phones get a general result.

Emergency radios and cell phones use different networks and frequencies, and they have different requirements. The free score gives a general result for cell phones; a building-specific answer is part of the paid work.

Phones are what tenants, staff and visitors live with every day. If phone service matters to you, say so in your request.

Emergency radiosCovered by the DAS Necessity Score.
Cell phonesA general result in the free score. A building-specific answer in the paid work.

Questions

Questions about the score

Does my building need a DAS?

It depends on the local code, the building and the outside radio signal. Many jurisdictions require emergency-responder radio coverage inside buildings, and a system is usually required when the building does not provide that coverage on its own. The DAS Necessity Score is a free first look at that question.

Is the score free?

Yes. The DAS Necessity Score is a free preliminary screen, with an emergency-radio result and a general result for cell phones.

How long does it take?

Less than 72 hours from your request. If we need more information first, we tell you what is missing within that time.

Does a favorable score mean we pass?

No. Only the required tests and the authority's acceptance establish that.

Will you tell us what to change?

The free score shows need or risk. Building-specific causes and changes are part of the paid work.

Start with the address and project stage.

Request a DAS Necessity Score