Master Plan Nashua Fire Rescue, NH
RESOURCE RELIABILITY
In this section, resource reliability is evaluated using several metrics to establish a global perspective on
Nashua’s ability to provide sufficient responding resources to meet service demand within the city. When all
units are available and in quarters, supplying sufficient resources is typically not a problem; however, when
multiple calls occur simultaneously, units are committed to incidents for extended periods of time, or when
insufficient resources exist to mitigate an emergency, further preparation and planning safely and effectively
must be completed.
Call Concurrency
First, call concurrency is evaluated. Call concurrency is a comparison of how often multiple calls are occurring
and placing additional demand on resources. In the next figure, a concurrent call is identified when a second
unit is dispatched to a separate incident prior to the first unit clearing the scene and becoming available.
When two incidents are occurring simultaneously and a third separate incident is dispatched, three
concurrent calls are present, and so on.
Figure 79. Call Concurrency, 2017-2019
Call Concurrency
Single Incident 63.3%
2 25.4%
3 7 .O%
4 or more 3.8%
When units are committed to an incident in Nashua, only one incident is occurring 63.3% of the time.
However, this also indicates that 36.7% of the time that units are committed at two or more separate
incidents and are unavailable to respond to additional calls. When comparing these findings to the ERF
analysis in the previous figure, Nashua’s ability to provide a sufficient number of firefighters to the downtown
area and central core of the city the majority of the time appears to be adequate while the response to
outlying areas, particularly the northwestern and southeastern portions of the city possesses the potential
for delayed responses and insufficient personnel to mitigate medium or high-risk incidents safely and
effectively.
Unit Hour Utilization
Another component that must be considered when evaluating Resource Reliability is Unit Hour Utilization
(UHU). UHU provides an expression of the workload placed on the crew assigned to that unit and can also
describe the amount of time that a unit is not available for response because it is already committed to
another incident. The larger the percentage, the greater its utilization, and the less available it is for
assignment to subsequent calls for service, training, and ancillary duties. UHU rates are expressed as a
percentage of the total hours ina year.
In May 2016, Henrico County (VA) Division of Fire published an article after studying its department’s EMS
workload. As a result of the study, Henrico County Division of Fire developed a general commitment factor
scale for its department. The next figure is a summary of the findings as it relates to commitment factors.
Emergency Services
ESC) Consulting International 119
