Abandoned calls
See Call Abandonment.

Access Key
A unique computer-generated letter/number combination that allows one employee to enter a website and complete the Employee Satisfaction Survey. The access key is deactivated once it has been used.

Agent Occupancy Rate
A measure of the average amount of time when employees are busy with incoming calls or dispatch activity. It can be viewed as "available time" or "ready time" and a reasonable cushion of excess agent availability should be included in staffing estimates as a safety factor (i.e. assuring the center is able to handle unanticipated surges in call activity). Researchers in commercial call centers report increased employee turnover and "undesirable" agent behaviors when agent occupancy rates exceed 85 to 90% over extended periods of time. Detailed records are needed to calculate actual occupancy rates, so the calculations used in the Tool Kit are based on agent occupancy targets.

Annual Call Volume (acv)
is the total number of calls processed by a communications center in a year. It is often reported as incoming calls only but a more accurate measure includes all call activity: incoming, internal transfers, and outgoing calls. Duplicate calls for a single incident, such as multiple wireless calls for the same car accident, should also be considered for inclusion in total call volume since they require a response and consume call-taker time.

Anonymous
There is no identifiable or traceable link between the respondent and the data, such as with the information provided by employees in the Employee Satisfaction Survey. Employee access is controlled with the use of unique access keys, and their submissions are completely anonymous. Not even the webmaster can link a response to a specific employee.

Authorized Positions
The number of positions in a communications center that are allowed to be filled by the budget or budgeting authority, or budgeted FTES. The authorized level may differ from the actual number of current employees.

Average actual time
The determination of Net Available Work Hours can be based on an average of the actual time employees used sick, vacation, FMLA, Military or other leave. Averaging real data for the previous full year, obtainable from the Human Resources Department or from employee records, will reflect the differences due to seniority (e.g., additional vacation time for senior people) and differences in the use of leave (e.g. FMLA, or military leave).

Average allocated time
A faster but less accurate measure of employee availability is to simply use the number of days employees are allocated (whether they use them or not in a give year). For example, you might figure two weeks (80 hours) paid vacation per employee, one sick day a month (8 hours x 12 months = 96 hours per year), one-and-a-half hours per day for lunch and two 15 minute breaks (50 weeks x 1.5 hours = 75 hours per year), etc.

Average call completion time
See Call Completion Time

Average Processing Time (apt)
is determined by adding the average telephone busy time and call completion or wrap-up time. Conceptually related to average call duration and calls per hour, it is a more general term that can be used for telephone activity alone, or for a combination of telephone and radio activity. For example, if the average time on the telephone is 1.5 minutes per call and another .5 minutes is the average time needed for associated activities such as data entry or dispatch, the APT = 1.5 + .5 = 2.0 minutes.

Average Speed of Answer
The actual time spent talking on the telephone as measured by telephone software.

Average telephone busy time
The actual time spent talking on the telephone as measured by telephone software.

Basic analysis structure
This refers to the time blocks that can be selected in the web tool used for hourly analysis of weekly activity (in the APCO Staffing and Retention Tool Kit). The use of time blocks makes it easy to compare call volume and staffing if the time block is based on shift length. Centers that use multiple overlapping shift lengths can use two hour blocks. The only limitation is that time blocks must be evenly divisible into a 24 hour day.

Blocked calls
Calls that receive a busy signal when all lines are being used.

Broadband
See Nationwide Public Safety Broadband Network (NPSBN)

Busy time
The time when a call taker is actually talking on the telephone or the dispatcher is actually talking on the radio. It is the time recorded by most software programs and does not include any additional time associated with a particular call or incident.

Commission on Accreditation for Law Enforcement Agencies, INC. (CALEA)
The Commission on Accreditation for Law Enforcement Agencies, Inc., in conjunction with APCO developed Standards for Public Safety Communications Agencies, and published The Standards Manual of the Public Communications Accreditation Program in January of 1999. CALEA defines size for stand-alone centers as the total number of authorized full-time personnel. They use three center size categories: A (1-15 personnel), B (16-75 personnel) and C (76 or more personnel). These categories are referred to as small, medium and large size centers in all Project RETAINS documents.

Call Abandonment
An incoming call that is abandoned when the caller hangs up before the call is answered. The number of abandons and the abandon rate are good quality indicators and generally related to speed of answer. Call abandonment is taken seriously by public safety communications centers, and all abandoned 9-1-1 calls must be called back.

Call completion time
The non-telephone time spent processing a call. It includes all additional time related to a call; time spent entering data in to the CAD system, handling the call internally, transferring calls, dispatching a unit to the scene, address verification, etc.

Call processing time
The amount of time spent on a call. This includes actual busy time on the telephone plus any additional time spent entering data for that call on the computer, into the CAD system, address verification, etc. There is a substantial difference in processing time if a call taker is simply routing a call to a dispatcher or ambulance service vs. providing emergency medical information and dispatching a field unit to the scene.

Call reporting software
Software commercially available for tracking telephone statistics that are not captured by the CAD system. Ideally such software can provide detailed information about the number and length of all incoming, outgoing, and internal transfer calls. Such information is vital to determining the number of staff needed to handle the workload (calculation of FTE needs is based on number of calls and average processing times).

Call Volume
A common term for the number of calls. Usually used with a time delineated qualifier such as annual call volume, or hourly call volume. Call volume is not about the length of calls or the nature of the calls. It is simply the number of calls and it is used to determine workload. Centers where each employee handles telephone and radio activity, may want to add the number of incidents dispatched to the number of telephone calls to obtain a more accurate indication of workload (number of CAD entries or incidents dispatched is considered a more realistic indicator than number of push-to-talk events).

Census Region
The United States Census Bureau divides the U.S. into four Regions: Northeast, South, Midwest, and West; and nine Divisions.

Communication Center
A centralized location for processing telephone calls. See Public Safety Communication Center.

Computer-Aided Dispatch (CAD)
A computer-based system that assists PSTs with activities such as call input, dispatching, call status maintenance, event notes, field unit status and tracking, and call resolution and disposition.

Confidentiality
Confidentiality means access to information is limited to specific people (e.g., researchers or a website administrator), and may not be reported in a way that allows an individual or individual center’s identity to be determined. Information that is confidential is not anonymous; there is a (protected) link between the data and the source of the data.

Console
The physical space where a call taker or dispatcher works, also called a work station or post.

Contract year
The base number of days or hours in a "full time" job; typically 2080 hours per year. The term applies to legally binding formal written contracts, but in "right to work" states, such contracts do not exist.

Coverage Position
A job category in which the number of employees is determined by the need to provide service regardless of the workload. The "coverage" may refer to a particular task, a specific work station, post, or console that must be staffed or "covered" for a given length of time, usually continuous service 24 / 7 / 365. For example, a fire-rescue or law enforcement dispatch console that is covered around the clock regardless of the amount of call activity is a "coverage" position. Small centers where one or two employees can handle all telephone and dispatch activity around the clock with a minimum number of staff must staff for "coverage" of those consoles. Shift supervisor or shift manager is a "coverage" positions if someone must fill that position during all shifts, or even for one or two shifts a day (note that it does not need to cover 24 hours for it to be a coverage position). A center that can handle the call load with minimum staffing around the clock must fill a basic number of coverage (sometimes called "fixed") positions. A center that requires a separate dispatcher to cover each of five different consoles 24/7/365 has five "coverage" positions. If one console is used to cover several channels during the night shift, the number of positions used to calculate coverage needs should include an appropriate fraction.

Decimal Time
Decimal time is a way of displaying time in decimal format.  Rahter than representing one minute thirty seconds as 1:30 it would be represented as 1.5.  The times break down as such: :15 = .25, :30 = .50, :45 = .75, :00 = 0.

Decision Rule
A parameter set for determining when an additional employee will be scheduled to handle the workload. The hourly analysis tool (in the APCO Staffing and Retention Tool Kit) can be set up to round up at intervals other than .5; most programs have a default rounding rule: round up if over .5 and down if under .5; when exactly .5 round to the nearest even number. Providing additional control over the rounding process is intended to avoid systematically under or over estimating the number of staff needed to handle the incoming call volume.

Emergency Communications Center (ECC)
A facility with capabilities that include intelligence collection and monitoring, 9-1-1 multimedia traffic processing, full scale dispatch, and incident command capabilities.

Emergency Medical Dispatch (EMD)
A systematic program of handling medical calls. Trained PSTs, using locally approved guide cards, quickly and properly determine the nature and priority of the call, dispatch the appropriate response, then give the caller instructions to help treat the patient until the responding EMS unit arrives.

Emergency Medical Services (EMS)
A type of emergency service dedicated to providing out-of-hospital acute medical care, transport to definitive care, and other medical transport to patients with illnesses and injuries which prevent the patient from transporting themselves.

Employee Availability
Employee availability is a measure of the actual number of hours employees are available to handle a task, expressed as Net Available Work Hours (NAWH). It is calculated by subtracting the total hours an employee is on leave or in training from the total work hours (i.e. the number of hours in a year for a "full time" employee). This is referred to as "shrinkage" in commercial call centers. This adjustment is used for coverage and volume-influenced positions only. It can be calculated using the amount of time allocated or actual average time used for each category. Calculations based on actual employee data will address differences in vacation and leave time based on employee seniority. Time off that may be unique to a center could include: reduced workloads for new recruits, long-term disability, light duty assignments, leave without pay, unexcused absences, or turnover rate (based on an average for several years). See Net Available Work Hours for additional detail.

Employee Satisfaction Survey (ESS)
The Employee Satisfaction Survey (ESS) is composed of questions that were used for a national survey that was developed specifically for the purpose of understanding staffing and retention issues in public safety communications centers. Questions were based on a list of effective practices generated by the APCO Staffing Crisis Task Force in 1999, and refined in consultation with the members of the APCO Project RETAINS (Responsive Efforts to Assure Integral Needs in Staffing) Committee in 2003. Surveys were distributed to a random sample of managers of public safety communications centers across the nation. Managers provided numerical data and information about policies and practices in their center, and passed the employee surveys on to their staff. Employees responded to questions about their satisfaction with center policies and practices. Responses were received from 153 managers and 600 employees.

Employee Satisfaction Survey Long Version
Employee satisfaction was measured with 52 items in the original survey. These items were related to the work itself, the physical environment, supervision and management, the level of support provided by the center, scheduling policies and practices, and compensation and benefits. The 52 item satisfaction scale had a reliability coefficient of .94, indicating high reliability.

Employee Satisfaction Survey Short Version
The Employee Satisfaction Survey in the web-based Staffing and Retention Tool Kit is a shortened version of the survey. Factor analysis was used to reduce the original satisfaction scale and to select the questions for the ESS, resulting in a 16-item satisfaction scale. Additional questions, on topics that predicted employee satisfaction, are also included in the ESS. These other questions are about overtime, recognition, the overall performance of the center, and future plans. The 16-item satisfaction scale was pilot tested in 2005 by four call centers and a total of 317 employees. A .86 reliability coefficient for the shortened satisfaction scale was also high.

Erlang
An Erlang is a unit of measurement for the call traffic within an hour. For example, if a center receives 30 calls in one hour and each call lasts 5 minutes, the total minutes of traffic in the hour is 150 (30 minutes x 5 minutes = 150 minutes). But there are only 60 minutes in an hour so that 150 minutes is divided by 60 to calculate an Erlang (150 ÷ 60 = 2.5 Erlangs). The higher the Erlang number, the busier the center. The Erlang is named after its inventor, Agner Krarup Erlang of Denmark, and goes back to 1909 when he published The Theory of Probabilities and Telephone Conversations. There are several telephone-traffic models (formulas) that utilize the Erlang. The Erlang is generally used to estimate the number of telephone lines that are needed, but formulae that have been developed to model queuing activity allow estimates of staffing requirements based on call activity (i.e. Erlangs).

First Responder Network Authority (FirstNet)
The Middle Class Tax Relief and Job Creation Act of 2012 created FirstNet as an independent authority within the National Telecommunications and Information Administration to provide emergency responders with the first nationwide, high-speed, broadband network dedicated to public safety.

Estimate Staffing Needed for Coverage Positions

Note: Coverage positions must be covered regardless of call volume or level of activity.

Estimate Staffing Needed for Volume-Influenced Positions (tkesfvip)

Worksheet E: Calculating Staffing for Volume-influenced Positions

Estimate Staffing Needed for Volume-influenced Positions Note: The number of Volume-influenced positions is based on call volume or activity level. Position: Workload: A. ____________ calls Total Call Volume for this position (TCV), from phone records B. ____ minutes per call Average Processing Time for this position (APT), from phone records C. ______ calls hourly Hourly Processing Capability (HPC) = 60 ÷ B D. _________ call hours Workload in hours (W) = A ÷ C Employee Availability: E. _______ Net Available Work Hours - enter average NAWH from worksheet F. _______ Agent Occupancy rate - enter AO, convert percent to decimal G. _______ True Availability per person (TA) = E x F Staff Needed: H. _______ Full Time Equivalent base estimate (FTE) = D ÷ G I. _______ Turnover Rate from retention worksheet - convert to decimal J. _______ Full Time Equivalent required to accommodate turnover, prior to any adjustments based on quality indicators: FTE = H x (1 + I) ___________ = Estimated Staffing Need (in FTEs from Step J above) FTE = Workload ÷ Employee Availability x Turnover Adjustment

Fixed Position
Positions that are covered at a minimum level independent of call volume and regardless of the activity level. See Coverage position.

Full Time Equivalent (FTE)
The number of full time staff it takes to cover a position for one shift. If a center schedules two half-time employees to cover one position, the two employees make up one full time equivalent, or one FTE. Each half-time employee would be .5 FTE.

Function Position
A job that is based on a specific task or function necessary to operation of a communications center. A "function" position is independent of call volume and does not require coverage. For example, if all of the time of a manager is spent on management functions, manager is a function position in the center. Additional examples of "function" positions may be training coordinator, quality assurance coordinator, radio/technical specialist, tape puller, or any other job that serves a specific role not related to covering a specific position or responding to call processing activity in the center.

Geographic Information System (GIS)
A system designed to capture, store, manipulate, analyze, manage, and display all kinds of spatial or geographical data.

Hourly Analysis
The process of analyzing call volume and staffing needs on an hour-by-hour basis, generally for a week at a time. An hourly analysis may be based on a specific week selected because it is "typical" or unique in some way (e.g., an unusually high level of activity surrounding a holiday or special event such as a football game), or averages of weekly activity (e.g., by quarter, by month, by month, by season, etc.). The bonus tool in the Staffing and Retention Tool Kit uses an hourly analysis.

Hourly Processing Capability (HPC)
The total number of calls that can be handled in an hour based on the average processing time (APT). It is a measure of potential call handling if every minute of the hour is devoted to processing calls. The number is an indicator of the maximum number of calls that can be safely handled in an hour. HPC can be determined indirectly by analyzing call abandonment records (i.e. callers hang up and call again if they feel they have been on hold too long). If the abandonment rate consistently increases when call volume exceeds a certain ratio of calls to call takers, you know the center has reached the hourly processing capability. For example, if 12 agents typically handle incoming calls with an abandonment rate below 5%, but when the incoming call volume exceeds 200 calls per hour the abandonment rate goes up, the indirect HPC for that center is about 16.7 calls per person (HPC = 200/12 = 16.66). Other quality indicators such as percentage of calls answered within 10 seconds can be used for an indirect estimate of HPC. The HPC is dependent on the number of tasks that need to be completed with each call, and will be shorter for agents that simply route a call through to the appropriate dispatcher vs. an agent that handles all aspects of a call from pick-up to dispatch.

Incoming Call Volume
The total number of incoming wireless and wire-line calls received in a given time period.

Information Technology (IT)
The study or use of computers for storing, retrieving, and sending information.

Mean
The average of the responses. (Ex: 3 + 6 + 8 + 11 + 15 = 43 ÷ 5 = 8.6)

Median
The "middle number" in the list of responses. (Ex: From the list 3, 6, 8, 11, and 15, the median number is 8)

Minimum Staffing
The minimum number of staff scheduled at any time during a given period of time based on experience, contract, legal requirements or previous staffing studies. Set the hourly analysis tool so that the calculation never goes below the minimum.

Nationwide Public Safety Broadband Network (NPSBN)
A nationwide wireless data network dedicated to public safety.

Next Generation 9-1-1 (NG9-1-1)
A secure, nationwide, interoperable, standards-based, all-IP emergency communications infrastructure enabling end-to-end transmission of all types of data, including voice and multimedia communications from the public to an Emergency Communications Center.

Net Available Work Hours (NAWH)
NAWH is calculated by subtracting the total hours an employee is out of the building or out of the room and unavailable for handling the core function(s) of call taking or dispatch from total work hours. When determining NAWH for a position averages should be used for all employees in that position. For example, if the number of total work hours for call takers is 2080 hrs per year (i.e. the number of hours in a year for a "full time" employee), and the averages for all call takers are 240 hours vacation time, 80 hours of sick leave, 16 hours of personal leave, 24 hours of training, and 78 hours for lunch/breaks, the total time they are actually available to answer calls is 2080 minus 240 + 80 + 16 + 24 + 78 = 2080 - 438 = 1642 hours. See Employee availability. Same as Net Annual Work Hours.

Over hire
Some centers are authorized to hire additional employees, beyond their authorized levels, to accommodate predictable changes in employment levels due to turnover, FMLA, etc.

Performance Targets
Quality indicators that serve as a proxy for communications center performance. Common indicators are the percentage of calls that are answered within ten seconds, the percentage of calls answered within three rings, the call abandonment rate, the average speed of answer (ASA), blocked calls (busy signals), etc.

Position
A job in a communication center that has specific requirements and duties. For example, some centers have a call taker/dispatcher position in which all employees do both call taking and dispatch whenever they are on duty: the two tasks are not separated and each employee handles all calls from pick up to completion. Some centers use the term "telecommunicator" to signify the union of these duties, but whatever the name, the position is the same. Some centers divide the task into separate positions, with some individuals designated as "call takers" and others designated as "dispatchers." The position is "call taker" or "dispatcher" even though the individual employee who is filling that position at any given time may be cross-trained and move easily from one job to the other. The term position does not refer to rank or salary classifications. The different positions within a communication center are typically based on function, coverage needs, or call volume. Staffing for combined call taker/dispatch positions may be based on either coverage or volume-influenced calculations, depending on the size and distribution of incoming calls in the center. Dispatch positions tend to be based on coverage needs. Some centers use a combination of 8-hour and 10-hour positions. Call taker positions tend to be volume-influenced. See function position, coverage position, and volume-influenced position for additional detail.

Post
A physical space, console or work station where a specific task or job is completed. For example, there may be specific posts devoted to call taking, while other posts are devoted to law enforcement dispatch, fire-rescue dispatch or emergency medical dispatch. An employee at a dispatch post may pick up incoming calls if the call takers are unable to handle the pace of incoming calls, but the primary task at that post is dispatch.

Probationary
Staff that has been recently hired or is still in a "probationary" period that usually includes intensive training and/or mentoring. Also referred to as "new hires" in the retention rate calculator.

Problem Based Learning
An instructional strategy that confronts students with the statement of a problem prior to instruction, creating a need to know and a purpose for learning. It is an instructional strategy that has been used with good success in medical schools, law schools, K-12 education, college and university courses and graduate schools. It is based on the way we naturally learn (i.e., we are confronted with a problem so we seek information that will help us understand and address that problem), so it increases student motivation and retention of the information that is learned.

Project RETAINS
See RETAINS.

Public Safety Answering Point (PSAP)
A facility equipped and staffed to receive emergency and non-emergency public safety calls for service via telephone and other communication devices. Emergency calls for service are answered, assessed, classified, and prioritized. See also Emergency Communications Center.

Public Safety Telecommunicator (PST)
Public Safety Telecommunicator. An individual employed by a public safety agency as the first of the first responders whose primary responsibility is to receive, process, transmit, and/or dispatch emergency and non-emergency calls for service for law enforcement, fire, emergency medical, and other public safety services via telephone, radio, and other communication devices.

Recruit
A newly hired employee, typically still in training or within the probationary period. Recruiting is an area of great interest to managers who have difficulty finding employees who can handle the work and finding enough to comfortably handle the amount of work. Study II explicitly solicited information about recruiting strategies that were particularly effective for finding potential call takers and/or dispatchers. Those strategies are available in the Employee Satisfaction Survey report and the Effective Practices Guide.

RETAINS, Project RETAINS
(Responsive Efforts to Assure Integral Needs in Staffing), an APCO initiative that resulted in national studies on staffing and retention in America’s Emergency Communications Centers.

• Staffing and Retention in Public Safety Answering Points (PSAPs): A Supplemental Study – 2018 - APCO commissioned a follow-up study with George Mason University Center for Social Science Research that builds on both the 2005 and 2009 reports to observe how these conditions have developed over the past nine years, to reassess the perceived utility and utilization of Project RETAINS, and to add a new section detailing the use and knowledge of new technologies in ECCs. (Insert hyperlink to download report)
• APCO Project RETAINS Compiled Report - The intent of this deliverable is to synthesize the findings of both reports to assist public safety communications professionals. The main topics covered in this report include the effects of the economy, salary, next generation technology in communications centers, psychological distress, the dispatcher position and consolidation. Download Report
• APCO Project RETAINS Next Generation Report - This report on the second national study sought to extend knowledge of communications center staffing issues not addressed in the first study and to gauge the degree to which Project RETAINS had proved useful. This areas of focus for this study included current staffing challenges facing communications centers, the current national turnover rate, analysis of organizational commitment and psychological distress and guidelines for staffing a dispatch position. Download Report.
• A National Study - Reports and Surveys - This summary report of all Project RETAINS research, includes the results from Study I, which surveyed both managers and employees, and Study II which surveyed managers, but not employees, of center with 76 or more employees. Download Report. Download Surveys.
• Technical Report - This document provides detailed information about the statistical tests and analytical procedures that were used along with item-by-item analyses. Download Report.

Retention
The ability of an organization to keep its employees, as opposed to losing them as a result of voluntary or involuntary departure decisions. Retention is the opposite and complement of turnover.

Retention Rate
Percentage of employees that remained with an organization during a given period of time (usually annually). Calculated as [1 - Turnover Rate] * 100. A more accurate calculation, if data are available, is to use an aggregate of monthly averages.

Scheduling
The process of assigning employees to specific time slots. Staffing is the determination of the number of employees needed, while scheduling is the allocation and deployment of available employees.

Selection
The process of screening and selecting potential employees who are highly qualified and/or a good fit with the work.

Shift Relief Factor (srf)
The number of full time equivalent staff needed to cover a position that requires coverage on a continuous basis. For example if it takes 1.7 full time staff to cover one 8-hour shift (after deducting all leave and breaks from total annual work time), and the position must be covered 24 hours a day, 3 shifts X 1.7 = 5.1 FTE to cover the position around the clock.

Shift start time
You can set the beginning time on the hourly analysis tool to make it easier to see the relationship between call volume, staffing needs, and scheduling based on your current shift structure. If you enter data on the Excel spreadsheet, do not change the layout of the spreadsheet, the tool will automatically organize the data based on the shift start time you select.

Short Message Service (SMS)
A service that allows the user to send and receive short (maximum 160-character) messages independently of voice calls.

Shrinkage
The loss of employee availability due to time off for vacations, sick leave, etc. It is essentially the same concept as net available work hours, but focuses on lost time rather than available time - a glass half empty vs. a glass half full). The term shrinkage is often used by commercial call centers.

Staffing
Staffing is a broad terms that includes the process of determining the number of employees needed to handle a specific set of tasks and/or a given workload, finding, hiring and keeping the appropriate number of employees. It differs from scheduling in that staffing is about the number of employees needed to handle the work load, whereas scheduling is about the allocation and deployment of those employees.

Standard Operating Procedure (SOP)
Written procedure prescribed for repetitive use as a practice, in accordance with agreed upon specifications aimed at obtaining a desired outcome.

Text to 9-1-1
Text-to-911 is the ability to send a text message to reach 911 emergency call takers from your mobile phone or device.^Note

Text to 9-1-1 Session
A text to 9-1-1 session is defined as the time from when a text to 9-1-1 is received to the time the communication ended.

Time period for analysis
Refers to the time period used to obtain the hourly data entered in the Analysis of Hourly Staffing Needs for a week. The hourly data can be an average from several weeks or months, a week selected at random, a week selected because it is fairly "typical" or a week selected because it is unusually busy. Be sure to record identifying information about the data, such as beginning and ending dates, phone lines included, and a brief description of any unique aspects of the time period (e.g., busy season, big game in town, etc.).

Total Call Volume (TCV)
Total Call Volume is used to estimate staffing needs for volume-influenced positions. Call volume is simply the number of calls; it is not about the length or nature of the calls. All calls should be counted, incoming, lateral or transfer calls, and outgoing calls contribute to the total number of calls handled. As long as a call requires time, it should be included in the total. Note that Total Call volume can be for any time period, and it can be for any position, as long as the data is available in that format. For example, it may be appropriate to estimate staffing based on Total 9-1-1/Emergency Call Volume if all emergency calls are handled by designated call takers. If administrative calls are tracked and counted separately from emergency calls, and the center staffs these positions based on volume, staffing should be estimated for the specific position. If incoming calls are distributed to whomever is available at the time, it makes more sense to lump all calls together and estimate staffing needs based on total call volume for the call taker position in the center. Most centers will use total annual call volume for this calculation, but the tool can also calculate staffing needs for shorter periods of time such as quarterly or during a busy season (but remember to make the time adjustment in all tools). Centers where each employee handles telephone and radio activity, may want to add the number of incidents dispatched to the number of telephone calls to obtain a more accurate measure of workload (number of incidents dispatched is considered a more realistic indicator of workload than number of push-to-talk events).

Device for the Deaf (TTY/TDD)
A machine that uses typed input and output, usually with a visual text display, to enable individuals with hearing or speech impairments to communicate over a telecommunications network.

Turnover Rate
The ratio of the number of workers who had to be replaced in a given time period to the average number of workers. Project RETAINS research calculated turnover as the percentage of all current positions that required replacement workers. Calculated in the Tool Kit as the total number of staff that leave employment in a given year, for any reason (i.e. both voluntary and involuntary separations), divided by the total number of employees that year. Also known as attrition rate. A more accurate calculation, if data are available, is to use an aggregate of monthly averages.

Voice over Internet Protocol (VoIP)
Technology that permits delivery of voice calls and other real-time multimedia sessions over IP networks. Communication services that originate or terminate via IP networks rather than the circuit-switched public switched telephone network (PSTN).

Volume-influenced positions
Jobs within a communication center that require different levels of staffing based on the workload; positions that require additional employees to accommodate daily, weekly or seasonal variations in call volume. Job categories or tasks where the number of employees on any given shift is determined by the activity level ("volume") of incoming calls and/or incoming calls and dispatch. For example, if the number of call takers on duty is different at different times of the day, different days of the week, or different seasons based on the number of incoming calls, the call taker position should be considered a "volume-influenced" position.

Staffing for volume-influenced positions is based on the total call volume for that position (usually total annual call volume), and the average time it takes to process each call. The average processing time is used to calculate call handling potential or hourly processing capability an average number of calls that can be handled by agents if they are busy every minute of the hour. The average processing capability and the total call volume are used to transform total workload into total hours of work to be done. Adjustments are made for employee availability based on Net Available Work Hours, and a reasonable target for Agent Occupancy rate (expressed as a percentage of actual busy time). The result is a number of full time employees that are needed to handle an annual workload of a certain number of calls at a given rate of calls per hour.

Workload
An hourly measure of the work. Calculated as the number of hours spent processing telephone calls or handling calls and dispatch. It is determined by dividing total call volume by the average hourly processing capability (W = TCV / HPC). For example, if the Call Volume is 250,000 calls, and the average number of calls that can be handled in an hour is 30, W = 250,000 / 30 = 8333. The workload is expressed as 8,333 hours of call processing time.