EMS Vital Signs Dashboard
Contra Costa County

Contra Costa County is located in the San Francisco Bay Area east of San Francisco. With its 715 square miles, the county borders Alameda County to the south and San Joaquin County to the East. The Bay Area coastline borders the west and north sides of the county. The county is the 2nd most industrialized county in the state with a population of approximately 1.14 million people. Our Emergency Medical System (EMS) responds to 104,000 events a year and transports approximately 81,000 patients a year. The county has 8 hospitals. There are 12 First Responder Fire Agencies and 3 transporting agencies that respond to medical calls.

The Contra Costa County EMS Agency has created EMS Vital Signs to communicate with our community and our partners the health and operation of our system. This site is continually updated with data from our providers as they respond to 911 calls to our citizens and visitors.

Responses and Transports

When you call 911, multiple resources and system components are initiated. The person who takes the call is professionally trained to ascertain the details of the incident and send the most appropriate resources as fast as possible. For medical calls our call centers utilize the nationally recognized Emergency Medical Dispatch (EMD) process. This process is a highly refined process to ask appropriate questions to determine the acuity of the incident and provide life-saving instructions prior to arrival of EMS personnel. The acuity determines how the responding units get to you. Based on the answers to the questions asked, an ambulance may be sent to you Emergently or Non-Emergently. The former is with their lights and sirens and the latter is as layfolk would drive. At some point during the phone call, and you may not even notice it, law enforcement, fire engines, and ambulances have started making their way to you.


A response is when EMS resources arrive at your location.


A transport is when an ambulance actually transports a patient from the incident location to a hospital for further evaluation and treatment.

Responses by City

Time Performance

Response Time. EMS system performance is often measured by the time it takes to get an EMS resource to you when you call 911. The dispatchers know where all the ambulances and fire resources are in the county. The most appropriate ambulance and fire resource is dispatched to your location and that’s when the response clock starts. The clock stops when the ambulance unit arrives at your location. The duration between those two times is the Response Time.

Time to Definitive Care. The time from when the call taker has enough information to send EMS to you, to the time you arrive in the Emergency Room is called the Time to Definitive Care. This is also another important measure of an EMS system.

Median Response Time (minutes)

Median Time to Definitive Care (minutes)

Emergent Response Times by City

Call Characteristics

Determinant. As mentioned above, the 911 call taker attempts to determine the acuity of the incident. Once the EMD process is complete a determinant is reached and entered into the computer aided dispatch system (CAD).

Primary Impression. The paramedics and emergency medical technicians (EMTs) classify the injury and/or illness based on objective and subjective observations, we call that the Primary Impression.

Interventions. The primary impression helps guide the EMS provider as to what care and treatment (interventions) are given to the patient. Interventions could be as simple as applying a band aid up to electrical shock of a person’s heart.

Below we have a list of what types of calls we respond to listed by primary impression. We are also listing paramedic and EMT interventions to show what types of treatments we’re providing.

About the Data

• Data provided by FirstWatch on an ongoing basis, updated daily.

Ambulance photo credit: Karen Wright