FAQ: Standby Duty

To the best of my knowledge, the Pacific Tsunami Warning Center (PTWC) uses a unique system for providing or 24x7 response by two scientists to a natural disaster. This system is certainly unique within the National Weather Service (NWS), PTWC's parent agency. This duty rotation consists of a combination of the typical 24x7 shift duty that is common throughout NWS field offices, but also standby duty that I frequently have to explain to NWS personnel from other offices, the media, and the general public. I have therefore created this frequently asked questions (FAQ) list that I hope will provide some clarity for my NWS colleagues as well as the greater community at large.

What is shift duty?

Shift duty means having an employee in full work status committed to a specific period of duty (e.g., 0000-0800, 0800-1600, or 1600-2400). The National Weather Service uses shift duty in most of its field offices for 24x7 operations.

The table below shows an example of a shift-only duty rotation using 9 scientists with 2 scientists on duty at all times (A = 0000-0800 hrs, B = 0800-1600 hrs, and C = 1600-2400 hrs). Assuming no absences of any scientist from the rotation, the scientists will work a long-term average of 4.6 8-hour shifts per week. This conservative estimate should be considered a minimum number.


What is standby duty?

Standby duty is similar to on-call duty, in that an employee is required to go into official work status in response to a particular event, except that the employee in standby duty status must be at the workplace. You can read the full official government definition here. Before 2005 the National Weather Service used standby duty at its two Tsunami Warning Centers (TWCs) for 24x7 operations. Since 2005 both TWCs increased their staff and now only the Pacific Tsunami Warning Center continues to use standby duty (and even then it is combined with shift duty, see the next entry).

Standby duty differs from shift duty in that even though an employee on standby is at their duty station he/she is not considered to be working. Such an employee therefore has the freedom to engage in personal activities so long as those activities do not compromise the employee's ability to perform work as soon as they are required to do so. A period of standby duty is also typically longer than a work shift (days rather than hours) so an employee in standby status may sleep and his/her employer provides on-site housing or temporary quarters for this purpose.

The table below shows an example of a standby-only duty rotation using 5 scientists (the former TWC staffing profile) with 2 scientists on week-long standby duty at all times (S = standby duty). Assuming no absences of any scientist from the rotation and that 40 hours of work is performed during the scheduled standby periods, the scientists will need to serve a long-term average of 25.6 hours of standby per week in addition to their 40 hours per week. This conservative estimate should be considered a minimum number.


How are shift and standby duties used at the Pacific Tsunami Warning Center?

At the Pacific Tsunami Warning Center (PTWC) one scientist is always on shift duty, awake, and in the PTWC work spaces (either the operations area or a nearby office). One additional scientist is always available via standby duty, and may be in their office or his/her assigned on-site housing or shared quarters. Therefore, when a potential tsunami-causing earthquake happens any time day or night at least two scientists will respond, first the scientist on shift, followed by the scientist on standby, followed by any other scientists who voluntarily respond, even from off-site.

The table below shows an example of a shift+standby duty rotation using 9 scientists with 2 scientists on duty at all times (A = 0000-0800 hrs, B = 0800-1600 hrs, and C = 1600-2400 hrs). Assuming no absences of any scientist from the rotation and that scientists will work 8 hours out of every 24 hours of scheduled standby, the scientists will work a long-term average of 2.3 8-hour shifts per week and serve an average of 12.4 hours of standby duty per week in addition to their 40 hours per week. These conservative estimates should be considered minimum numbers.


How do event response times differ between shift and standby duties?

Shift duty provides the fastest human response, as an employee in shift status will be awake, working, and not engaged in any other activity. When an operation uses only standby duty then human response times will vary depending on what the person in standby status was doing (including sleeping) when called to work status, and can be anywhere from just as fast as a person on shift to a few minutes longer. If scientists in both shift and standby status are providing 24x7 coverage as they do at the Pacific Tsunami Warning Center, then there is no difference in response time since the scientist on shift responds no differently than in a shift-only system.  With the rapid availability of a scientist through shift duty, the limiting factor on response time becomes the availability of seismic data as earthquake waves move through the earth and are detected by seismic instruments, and so both the scientist on shift and the scientist responding from standby often have to wait for enough data to analyze an earthquake for its tsunami-causing potential.

Why is standby duty used instead of shifts?

Standby duty is used in cases where it is more cost-effective than keeping employees on shift at all times to provide 24x7 services. These cases tend to be ones in which employees are required to be rapidly available for work at unknown (effectively random) times. A good example is a fire department, in which the firefighters do not know in advance when and where the next fire will break out. The firefighters need to be near their trucks and other equipment, but would gain little response time by staying awake at all times waiting for the next alarm. Furthermore, to keep firefighters in full duty status at all times would require three times as many firefighters in each station (i.e., three 8-hour shifts).

Shift-only 24x7 duty makes more sense when work must be performed continuously or performed according to a schedule. For example, a high-production factory, an airline, a hospital, and a police department must have employees actually working 24x7 for these institutions to function properly.

In the National Weather Service, Weather Forecast Office (WFO) operations are usually “product driven” in that they must issue forecasts at regular intervals. Tsunami Warning Center (TWC) operations, on the other hand, are exclusively “event driven” like fire departments or WFOs during severe weather, and only need to respond to tsunami-triggering events (i.e., earthquakes) which occur at random, unpredictable times. TWCs have used standby duty, shift duty, or a mix of standby and shift duties to perform 24x7 operations.

How much does standby duty cost?

Because employees in standby status are confined to the workplace in addition to their normal work hours they can earn premium pay in addition to their base pay.  This pay is based on the long-term average of the employee's hours in standby status, is paid at a flat rate based on these standby hours, and can never be greater than 25% of their base pay but is typically less, especially for those with higher pay grades. Note that if employees earn standby pay they can earn no other premium pay for any other scheduled duty should they perform it, such as shift differential that would otherwise be earned for night work, Sundays, and holidays. Their standby pay, however, should include whatever shift differential they would have otherwise earned, so an employee performing both shift and standby duties may earn higher standby pay than if they performed only standby duty, but this pay can never exceed 25% of a GS-10 salary.

Implementing a standby rotation where it isn't already used does incur additional costs due to the construction and maintenance of sleeping quarters, whether these quarters are on-site full-time housing or bedrooms shared on a rotational basis. For on-site housing these costs may be offset with employee-paid rent. Sleeping quarters (i.e., bedrooms rather than full houses) integrated into a facility should not incur additional costs beyond their original installation as their maintenance becomes folded into the maintenance of the greater facility. Housing costs may also be offset by the reduced number of employees required to perform 24x7 coverage with standby duty.

Is 24x7 standby coverage more expensive than 24x7 shift coverage?

The relative costs of shift vs. standby duties vary depending on how many employees are in the duty rotation of a given office and how many are required to be available at any given time. As a general rule for shift duty, the fewer the number of employees used in a rotation, the more shift differential (for night workSundays, and holidays) will have to be paid to each employee as they will each spend more of their work hours on shift. For the same number of employees, the premium pay could be more expensive to compensate for standby duty. However, fewer employees are required to provide 24x7 coverage as they can be in standby status for far longer than the length of a shift (days instead of hours). Therefore, for a given office, using standby duty may be less expensive overall as it requires fewer employees, and thus fewer salaries.

For example, to have two scientists on shift duty at all times with no more than 40 hours per week per scientist requires a minimum of 9 scientists on staff (2 x 24 x 7 ÷ 40 = 8.4). On the other hand, to provide 24x7 coverage by two scientists on standby duty at all times with week-long standby stints requires only 2 scientists per week. Neither case allows for spare personnel to cover for absences from the duty rotation and implementation of either system typically has more qualified personnel available for duty than these mathematical minimums.

Does the use of standby duty carry any risks for a Tsunami Warning Center?

If only standby duty is used—that is, without shift duty alongside it—then slower human response times to events may result as all potential responders may be in their quarters asleep, and those responding from sleep may experience “sleep inertia” further slowing their response. Using only standby duty can also result in very long duty periods—more than two weeks—especially with low staffing numbers justified by a standby-only system and if some members of the duty rotation are absent for an extended time. These problems are minimized, however, if shift and standby duties are combined such that a shift person will respond first, more personnel are in the duty rotation, and duty cycles are rotated between shift and standby to prevent extended standby stints.

Like shift duty, standby duty can also present some health and safety challenges. If those on standby duty are alone in their quarters, or if standby permits those on shift to be alone while on duty (such as one person awake overnight), then these personnel could conceivably come to harm (injury, seizure, etc.) without their coworkers knowing about it until they fail to respond to a potential tsunami-causing event. Standby duty also has the potential to cause sleep deprivation, such as when numerous events occur close together in time (such as an aftershock sequence), or if a long event response is required early in a scientist's sleep cycle.

In Tsunami Warning Center (TWC) operations at least one of the two scientists on duty must be a more-experienced “senior” or “lead” scientist. Therefore, the Tsunami Warning Center Workforce Study expressed concern that the Pacific TWC's shift+standby 24x7 system could mean that the first responder to an earthquake (the scientist on shift) may not be one of these “leads” (p. 15). In practice the presence of a senior scientist is far more important after a TWC sends its initial tsunami warning because basic seismic thresholds (magnitude and location) trigger the first warning, but TWC scientists continue to analyze seismic and sea-level data after this initial warning to refine the tsunami forecast and, if necessary, upgrade, downgrade, or cancel the warning.

Does the use of standby duty have any operational benefits for a Tsunami Warning Center?

Since standby duty requires fewer personnel to provide 24x7 availability than shift work alone, standby duty frees up scientists to perform other work critical to the operation of a Tsunami Warning Center (TWC), such as outreach and scientific research and collaboration. Outreach informs both the general public and cooperating government agencies about tsunami hazards and TWC operations, and research leads to new methods for tsunami hazard mitigation, critical to improving TWC performance. Furthermore, both activities are mandated by National Weather Service Directive 10-7. This scheduling flexibility also permits TWC scientists to temporarily leave the duty rotation to receive training external to the TWC as well as accommodate personal needs such as sick leave, bereavement leave, and earned annual leave.

Standby duty also mitigates the well-documented negative physiological impacts of shift duty, particularly night shift work since each person in the duty rotation performs less night work than in a shift-only system. Though sleep interruptions occur in standby duty, they are random and less frequent than multiple recurring night shifts.

The use of standby duty at TWCs also has benefits not as easily quantified and documented as the cost-benefit analysis of salaries and other expenses. A scientist serving a night shift can become very fatigued, but a scientist responding from standby, even from sleep, can be well-rested. Quartering scientists on-site can provide a “critical mass” of nearby personnel who can quickly respond to both tsunamis and system problems even when not in duty status. If shift duty is used alongside standby duty, then the on-site quarters provided for standby duty can also be used by scientists preparing for and/or recovering from night shifts, therefore enhancing the personal safety of these scientists as they do not need to commute while sleep-deprived.

Which is better for a Tsunami Warning Center, shift of standby duty?

To answer this question, the mission of a TWC needs to be clearly defined and the decision to choose a style of 24x7 operations should require an honest cost-benefit analysis and include not only tangible cost of staffing levels, their salaries, and their facilities, but also less tangible costs and benefits to the mission, such as the best use of human resources and their morale.

If the primary goal of TWC operations is to have the quickest possible response to tsunami-causing events (earthquakes), then a shift-only system would seem to make sense.

In such a system two scientists would always be awake, on duty, and near the data-processing workstations in the TWC operations room. Following this logic to its inevitable conclusion, then these scientists should also spend their time in duty status exclusively in the operations room to minimize human response time even further.

Experience at the Pacific TWC (PTWC) shows, however, that with one exception that such a practice would make little difference. After most earthquake alarms the scientist on duty waits a minute or more for enough seismic data to be received by field instruments to perform a scientific analysis. The length of time spent waiting for these data is a function of the geographic density of instruments nearest to the earthquake's epicenter, and the scientist responding from shift will be waiting for data even though he/she may have responded from a different room or even a different building on site.

The one exception is the case of an earthquake detected within a local seismic network, a dense network of instruments in a small geographic area, such as Hawaii. Tsunami-causing earthquakes in Hawaii are much less common than other earthquakes that cause tsunamis, with recurrence rates on the order of decades rather than years. On the other hand, because Hawaii has this dense network of instruments the PTWC can rapidly analyze any Hawaii earthquake. In fact, when a large earthquake does occur in Hawaii, the PTWC notifies Hawaii State Civil Defense before the seismic analysis is complete so they are ready to act when the analysis is finished a minute or two later.

If a TWC is to perform other tasks besides rapid response to earthquakes, then the style of 24x7 coverage needs to be carefully considered.

In addition to analyzing earthquakes, TWC scientists must also analyze sea-level data in near real-time and execute forecast models to try to predict any possible tsunami's impact on affected coastlines. They must also clearly communicate the results of their analyses with emergency managers, the media, and directly to the public. Furthermore, PTWC scientists must develop most analysis tools in-house and communicate their findings between tsunami events as well as during events because part of a TWCs mission is to not only to react to tsunamis but to prepare both the TWC and its customers for future tsunamis (see NWS Directive 10-7).

To this end PTWC staff includes highly experienced and educated experts to not only deal with tsunamis when they occur but also to continuously develop and improve the tsunami warning system as a whole. These experts will need to perform some of their work during normal business hours in order to collaborate with their colleagues in the National Weather Service and other agencies. These experts will also need to perform some of their work away from the PTWC, whether to conduct site surveys for instrument installation or post-tsunami assessments, or to perform outreach with government agencies (both domestic and foreign) and the general public.

The use of standby duty along with shift duty at PTWC creates scheduling flexibility that facilitates these mission-critical functions to a degree that would be impossible with a shift-only system at current staffing levels. For the price of having one scientist instead of two instantly respond to all events PTWC's scientists are able to perform all mission-critical functions in addition to rapid earthquake response.

If the PTWC is required to use a shift-only 24x7 system without a staff expansion negative consequences would result.

Converting PTWC from a shift+standby system to a shift-only system would mean that existing staff will have to perform twice as many shifts as they do now. This greater commitment to the duty schedule will reduce scheduling flexibility and thus degrade PTWCs ability to further improve the tsunami warning system with research, development, and outreach. Even if the National Weather Service (NWS) expanded PTWC's staff to mirror those of other NWS field offices with single additional individuals dedicated to research and outreach, the remaining experts in PTWC's duty rotation would no longer be able to perform these duties and would likely seek employment where their talents can be put to better use and be better appreciated by their employer. This scenario is not speculation and according to the Tsunami Warning Center Workforce Study PTWC's sister TWC, the West Coast & Alaska TWC (WC/ATWC), is already at risk of this outcome as its “management and staff have a high potential for burn-out” (p. 14) and it augments its permanent staff with term employees and contractors in order to conduct their mission (p. 11).  The National Academy of Sciences' tsunami warning system report also expressed concerns about the poor use of TWC human resources (see Chapter 5), and as I said in my summary of that report:

The report frankly admits that the TWCs have “difficulties in 24/7 staffing” yet suggests only one remedy, to combine the staff of the two centers into a single center (p. 176). The report uses the example of WC/ATWC (p. 172) which has 9 scientists available for shift work. Two scientists are required to be on duty at all times, so in one week scientists need to cover 336 hours of shift work (2 x 24 x 7). Assuming a 40-hour work week, then the minimum staffing would be 8.4 scientists (336 ÷ 40), i.e., 9 scientists, which is the current staffing profile. Such minimal staffing, however, does not allow for any scientist to exit the duty rotation for official travel, training, illness, family emergencies, or vacation, despite the report's claim to the contrary (p. 172). As the report also recommends that TWC scientists interact with the scientific community at large by attending scientific conferences, workshops, etc. (pp. 173-173), the report should have included an alternative to merging the centers to the effect that more scientists will need to be added to the TWCs if the centers are not merged. For comparison, the NWS operates over a hundred WFOs that also have two scientists on shift at all times, yet each WFO typically has 13 staff members qualified for this type of work, or about 150% of minimum staffing, and they don't even have the research requirement of the TWCs (see NWS Directive 10-7, Section 3.3b). This lack of such an obvious “Plan B” suggests that the report's authors did not seriously consider alternatives to merging the centers, an expensive and complex proposition that NOAA/NWS may not implement.

Therefore, the only way to avoid the negative consequences of converting PTWC to a shift-only 24x7 operation is to expand its permanent science staff.