Why Not The PPDS?

Cynthia Murray

Cynthia Murray

Best Practices

Editor's Note: Click here to read part 2.

Many of our Protocol users recognize the benefits of the Medical Priority Dispatch System (MPDS®), where seconds can mean lives, Pre-Arrival Instructions are essential, and evolving research in the medical community is updated constantly for greater patient outcome.

Yet often these same users are hesitant to adopt the Police Priority Dispatch System (PPDS®), raising concerns about how the PPDS would impact their center. This two-part series will address common questions to resolve the uncertainty on the path toward Police Protocol implementation, first focusing on call processing times and flexibility.

Will implementing the PPDS lengthen our call processing times?

In a communication center setting providing medical, fire, and police services, it is common for police calls to comprise most of the call volume, so call processing times are a priority. A feared or perceived “increase” in these call processing times prevents many communication centers from utilizing the advantages of the PPDS.

Dave Warner, International Academies of Emergency Dispatch® (IAED) Police Protocol, Academics, and Standards Expert, explained that unfortunately, it is hard to predict the effect on call processing times when introducing the PPDS in a center that is currently operating on agency practices or routines. Individual processes lack standardization, as does their method for measurement.

Call processing times must be classified into specific components to determine efficiency:

  • How much time is spent collecting and verifying location, phone number, and incident information?
  • How much time is spent on protocol interrogation?
  • How much time is spent before a response is sent?
  • How much time is spent relaying information to responders?
  • How much time is spent providing critical caller instructions?
  • How do these statistics compare on high-priority calls?

Without data on each of these components, the best questions might be “How are communication centers able to pinpoint areas for improvement based on averages of unspecified data?” and “How could detailed statistics alone transform a communication center’s efficiency?” 

The PPDS enables communication centers to utilize tools built into ProQA®, which standardizes this process and records and retrieves accurate data for far more than average call processing times. Supervisors can build reports to isolate specific call types, response levels, Key Questions, etc., to identify trends for comparison and additional training on an individual, shift, or agency level.

If time alone is still the bottom line, the numbers show the proof is in the Protocol.

Chris Olola, IAED Director of Biomedical Informatics & Research, noted a trend of some communication centers attempting to save time by handling police calls through CAD only. However, this practice was tested in Dane County, Wisconsin (USA), in 2013, where a detailed analysis proved that calltakers spent considerably more time in CAD without a protocol due to non-essential questions, particularly during verification of the address, phone number, and problem nature.1

Nadine Zilke, Support Services Supervisor for St. Cloud Communications (Florida, USA), stated, “We have timed it, and we have had the same calltaker run through an actual call, this time using the [Police] Protocol. Even though sometimes the appropriate questions were not asked, and instructions were not given during the live call, using the Protocol was always quicker.”2

The PPDS has built-in early dispatch mechanisms to send responders often quicker than your center may be doing it now. The IAED Data Center tracks the elapsed time from launch of ProQA until a Determinant Code is assigned. Statistically, high-priority calls, such as those assigned a CHARLIE-, DELTA-, or ECHO-level response, are processed quickly using the PPDS.

The EPD spends a median of the following timeframes on questioning:

ECHO LEVEL = 26 seconds

DELTA LEVEL = 59 seconds

CHARLIE LEVEL = 65 seconds

PPDS v7.0, released in 2022, has had several improvements to streamline call processing times including earlier send points for additional resources, CHARLIE-level Determinant Codes for “just occurred” incidents, and tailored question sequences that address relevant information earlier for critical high-acuity calls.

The focus on reducing call processing times and providing earlier responses is important, particularly in high-acuity calls when lives or property are at risk. However, the focus on average call processing times alone does not address the efficacy of gathering key information for a safe and appropriate police response. These PPDS advancements, among others, focus on sending accurate information earlier to increase call processing efficiency, not just save time.

Is the PPDS flexible enough for our communication center?

The PPDS has been through some substantial redesigns since its original release in 2001. The first versions of the Police Protocol were patterned after the structure of the MPDS; however, the tactical approaches for handling police events differ vastly from the scientific, research based MPDS, and each communication center uses a tailored approach to public safety response.

As the world of 911 capability and standards has evolved, communication centers have needed more flexibility and agency-specific protocol capabilities to meet these needs.

“During the last several years, we’ve started gaining support from the communities that are willing to implement, test, and draft thousands of Proposals for Change (PFCs) to mold the Police Protocol into what it has become today: a flexible program that allows centers freedom to adapt the protocol for their own needs and use,” Warner said.

One significant improvement has been the advent of the optional Jurisdictionally Approved Questions (JAQs) that can be turned on or off depending on local policy. In PPDS v7.0, there are now over 250 JAQs that allow centers to tailor their caller interrogations to gather the specific information varying agencies require without changing how or when a response is sent. This streamlines interrogation times by disabling questions that may not alter a response agency’s local policies, or their operational needs.

Similarly, the PPDS software, ProQA, allows users to select Jurisdictionally Approved Instructions (JAIs) to determine the appropriate actions for the caller to take before responders arrive on scene. All Post-Dispatch Instructions that do not have an element of scene, caller, or responder safety can be enabled or disabled in the Protocol. As Zilke said, “We’re all the same in the sense that we’re all a little different.” The flexibility of enabling or disabling instructions allows agencies to prepare callers with distinct requirements.3

User groups have also discussed rewording questions to improve the caller’s response (or understanding) or replacing certain questions with a prompt the EPD could select if a condition applies, based off information gained in the interrogation.

“For the PPDS, this flexibility is only the beginning,” Warner said. “The success of the Police Protocol today goes way beyond the ability to turn a question on or off. We have cleaned up so many areas of the PPDS to significantly change the user’s experience.”


With more improvements to come in v8.0, the PPDS is an evolving system driven by the people who use it every day. Its built-in flexibility and tailored questioning maintain the standardization that drives efficiency and enables more informed responses. If your center has not yet implemented the PPDS, consider the potential benefits to EPDs, responders, and the community you serve, and reach out to learn more.


  1. Whitaker I, Barron T, Mcclay L, Olola C, Scott G. “Comprehensive Analysis: Dispatch Process in Dane County, WI.” Priority Dispatch Consultants, Inc. 2014; Oct 1. (accessed Nov. 2, 2023).
  2. Zilke, N. “Customer and Member Experience Videos.” Priority Dispatch Corp. https://vimeo.com/showcase/9737436 (accessed Nov. 2, 2023).
  3. See note 2.