It’s about 4:00 a.m. on your first overnight shift of the cycle. You had a busy day running errands, watching your child’s Christmas play, sitting down for dinner with the family before arriving to shift at 7:00 p.m. You’ve had a busy night with back-to-back calls, and haven’t made it back to the station since checking your truck at shift change.

You almost make it back to the station when you’re dispatched to yet another call: a reported single motor vehicle crash (MVC) in a rural part of your district. You and your partner are the first unit to arrive on scene of an overturned vehicle on a busy road. Your training kicks in and as you put the ambulance in park, you remember the “Safety First” mantra and ask yourself, “Is this scene safe?”

In reality, this scene is anything but “safe.” There’s the ever-present risk of serious injury or death due to being struck by a vehicle while on scene at an MVC. Apparatus positioning, reflective garments, and scene lighting may mitigate this risk; however, impaired drivers, adverse weather conditions, and the location of the emergency continue to be risk factors out of control of emergency responders. Despite this risk and ever-present danger, we continue to provide lifesaving care to people in unsafe environments daily.

As you don your reflective traffic vest and size up the scene, you see a single vehicle overturned off the roadway, leaking fluids from the engine compartment. You hear moaning from inside the car and see a young female lying crumpled in the driver’s seat with blood oozing from her mouth and nose. You hear gurgling respirations. You see a child seat in the back of the vehicle. It appears mangled but empty.

The local volunteer fire department has been dispatched, and a rescue truck is on the way, with an ETA of approximately eight minutes. You’re not sure your patient can make it that long; you’re concerned about her airway. What do you do?

Scene Safety? ‘It Depends.’

This is the reality of our jobs. As first responders, we have a serious and noble mission to preserve human life, to rescue those in peril, and to be a calming, stabilizing force in chaos. Our standard workspaces represent inarguably hazardous environments ,and we’re exposed to risks, both known and unknown, on every call.

Take, for example, the label inside standard turnout gear reading “[Rescue] operations are an ultra-hazardous, unavoidably dangerous activity …” (See Figure 1.) Our work is unavoidably dangerous as a baseline; our efforts are directed at mitigating that risk (as the gear manufacturer mitigates their legal risk with this label), not believing we can remove it entirely. Danger of some sort, according to this legally driven label, is unavoidable.

Figure 1: Warning printed on label inside standard turnout gear

If we train our responders to put safety as the first absolute principle, does it mean we stop fighting fires or extricating people from vehicles until technology has been developed that ensure baseline safety rather than baseline danger? Of course not. But, in a philosophy that’s perhaps itself dangerous, we continue to preach “safety first,” while simultaneously and paradoxically encouraging our personnel to normalize risk and push past the everyday and obvious warnings.

All too often, we teach cookbook training as the best risk mitigation—essentially, if you follow these steps, you can safely ignore the warning inside of your turnout gear. The truth is, emergency services are far safer today than they were 20 years ago, but risk is still high. No amount of training will ever make the risk zero or the possibility of “safety first” either a philosophical or operational reality.

So how do we keep first responders safe while still effectively accomplishing the collective, yet inherently dangerous, mission? Put safety third.

The Safety Third Concept

The concept of “Safety Third” isn’t new. Actor and television personality Mike Rowe is a champion of workplace safety and popularized the phrase through his show Dirty Jobs in 2009. Through several seasons of taping the show, Rowe and his crew suffered numerous injuries while working with professionals from many different fields. Throughout his experiences, he noticed numerous reminders of “safety first” through banners, signs, and Occupational Safety and Health Administration (OSHA)-mandated equipment and policies. Rowe noted that his injuries most often occurred when he let down his guard. He contends that constant reminders of “safety first” lose their impact and can create the illusion that someone else is looking out for the employee, especially if operations frequently do not, in fact, put safety first. He points out that, although many regulations exist to attempt to protect workers, “Just because you are in compliance doesn’t mean you’re safe.” Mike and his crew started using the phrase “Safety Third” to remind each other that safety was ultimately their individual responsibility, and was more complex than an absolute first priority.

Safety Third has quickly found its way into popular culture. Websites sell Safety Third T-shirts that depict the irony of safety mantra by displaying images of people engaged in reckless activities or with injuries such as severed fingers. This phrase has also come into popular use at the Burning Man festival, an annual gathering in the desert of Nevada billed as a festival celebrating “radical inclusion, self-reliance and self-expression,” among other principles.

Is there a place for Safety Third in EMS? As first responders, we constantly participate in a risk-reward balancing act. The mission of the first responder will always involve risk. The reward may not always be worth the risk. Groups with different missions may have a different approach to risk mitigation and the relative importance of safety within their missions.

It may not be appropriate to take a Safety Third approach with community education groups, such as Boy Scouts, Girl Scouts, or church or school groups. These groups formulate missions around teaching life skills, common sense and character development of youth. These missions are rarely time sensitive and don’t generally involve life or death decisions in real time, so placing the participants in any considerable danger would arguably tip the balance too far for most people’s comfort. Canceling the mission at the first sign of danger and rescheduling after further risk mitigation is likely an acceptable alternative.

However, EMS organizations have begun asking whether or not safety is truly the first priority for our missions, including our own work on this topic within the Carolina Wilderness EMS Externship (CWEMSE).

CWEMSE was founded in 2011 with the intent to become a crucible for training medical students and emergency medicine residents in the field of wilderness EMS. The Externship is a month-long, immersive experience guided by the principle of esse quam videri, the state motto of North Carolina, which means “to be, rather than to seem to be.”

The training is experiential in the truest sense. Rather than lectures or classroom-based instruction, the Externs (as they’re called) learn primarily from direct insertion into the EMS system in Burke County, N.C., home to one of the highest volumes of wilderness EMS callouts on the East Coast. It’s the educational philosophy of the Externship that lessons on hypothermia are learned best when cold and wet, and that no PowerPoint presentation can impart lasting wisdom about medical care in extreme environments quite as well as spending hours providing medical care in extreme environments.

To effectively accomplish this mission, Externs are selected from a highly-qualified applicant pool and are required to have substantial out-of-hospital medical care experience, as well as well-honed wilderness travel and backcountry living skills prior to application submission. Over the first six years, Externs and faculty debate and test various teaching models and concepts within the realm of wilderness medicine and/or EMS education. In addition to developing the concept of “horizontal hierarchy” among EMS providers1 and exploring a “train to failure” educational philosophy, the Externship has heavily debated the role of safety in its operations, as well as EMS operations in general. This has resulted in refinement and adoption of a Safety Third philosophy as a more realistic expression of actual EMS education and operations.

In this article, we’ll share what we’ve developed, which for us has fueled a fruitful conversation about the role of safety, job satisfaction, and task-oriented thinking among EMS providers.


Experience in the austere and wilderness medicine environment has resulted in the refinement of a Safety Third philosophy that’s a more realistic expression of actual EMS operations.

Rowe is correct in pointing out that the job of the first responder would never be accomplished if the worker put safety first every time.2,3 9-1-1 callers don’t call for help because they’re in a safe situation. The mission to bring a caller to safety begins with one or more first responders getting in a vehicle and driving, an activity proven to be one of the most dangerous activities in the United States.4 Were safety actually first, they’d never even take this first step. Moreover, these responders are often driving at a higher rate of speed than normal, through intersections, and around unassuming vehicles and pedestrians, leading to even more risk.

And even in an alleged safety-first environment, risk of injury and death among first responders is high when compared to other occupations. This statistic is true despite risk mitigation strategies and despite the (probably untruthful) industry mantra that safety is the first priority. In fact, risk for back injury and exposures to harmful substances is the highest source of injury among EMS workers, closely followed by slips, trips and falls, MVCs, and assaults.5 Each of these occurrences can be seen as intrinsic to the work an EMS provider does; they aren’t particularly surprising, and they’re unlikely to ever be completely erased by putting safety first. Instead, this would require implementing more complex mitigation strategies that balance mission completion with safety.

From the moment students begin the journey to becoming first responders, they’re taught to utter a seemingly simple phrase in order to acknowledge that hazards exist on scene, and to instill in them the idea that first responders shouldn’t enter a scene until the scene is secure. At the start of every testing scenario, the student says, “BSI (or PPE)”, and then asks, “Scene safe?” As a student progresses through numerous scenarios required throughout his or her schooling, this phrase typically becomes less of a question and more of a statement, “BSI. Scene Safe.” As long as the phrase is voiced, the student continues on the path to passing the test. If the scene is considered to be unsafe, the testing administrator soothes the students by noting “law enforcement has secured the location” or uttering some other dismissal of the supposed risk.

In our training and testing environments, scene safety becomes a binary “safe” (i.e., proceed to deliver care) or “unsafe” (i.e., do not proceed to deliver care). However, we know in reality that scene safety is never binary and that decisions about care delivery are far more complex than never entering a scene that is “unsafe.”

No scene is fundamentally “safe” for first responders and no scene can ever truly be secure, but first responders have a duty to act, balanced by an obligation to assess relative risk. Furthermore, safety doesn’t stop at scene entry, which these “scene safety” teaching and testing modalities usually fail to acknowledge. Every scene is dynamic and varying risks present themselves through every scene. Just as we frequently reassess our patient, we should also continuously reassess our scene.

As it currently exists, first responder education too often fails to teach students to recognize the true hazards of their profession until faced with those hazards daily. In school, students learn about cases of gunmen hiding in trees waiting for responders to arrive, but they fail to learn the more common risk of the icy front steps of the home to which they’re responding, the mole hole in the front yard, the tree limb dangling dangerously over the park bench waiting to crush the medics and patient below as they set up for intubation.

These hazards don’t necessarily have anything to do with the patient condition or family dynamic, nor would they be acknowledged as an “unsafe” scene during an oral exam or practical test. They’re not necessarily present as a malicious threat or noted in the pre-call data sent by 9-1-1 dispatch. They’re simply present.

Acknowledging & Preparing for Risk

A shift from Safety First to Safety Third drives a different approach to scene entry and patient care. Each provider acknowledges there’s risk in entering every scene and acknowledges that risk varies in degree with each scene and throughout the operation of each call. Hazard mitigation lies heavily in training and acknowledgement of personal limits, comfort level, and level of spatial and temporal awareness by every provider.

Different models currently exist for more sophisticated risk management strategies than providing care only when the scene is “safe.” The Swiss Cheese Model described by James Reason in Human Error is one such model worth reviewing.6 He looks at a block of swiss cheese and cuts the block into a number of slices, such that each slice represents a point where a bad outcome may be stopped. His idea is that in order to achieve catastrophic error, the holes in the individual slices of cheese must line up perfectly so that the impending error is never caught.

Anesthesiologist and wilderness medicine physician James Lieberman proposes PEEPS as a type of checklist to avoid catastrophic failure in wilderness scenarios in particular.7 PEEPS stands for:

  • Person (an individual’s health and well-being);
  • Environment and conditions;
  • Equipment;
  • Partner or team; and
  • Scenario (i.e., what do you do when the scenario does not go as planned? What is the emergency plan?)

Echoing Rowe’s contention that safety is an individually derived value that varies and not necessarily an organizationally derived value where more Safety First policies don’t equate to more safety, consider a recent actual case of a video from a police department operation, and a response to that operation from an officer of a separate department. These departments likely have different policies, but let’s pretend they have the same policies regarding safety of their officers. These officers work in similar size cities with similar crime rates, so this comparison may not be too abstract.

The video shows a police officer performing an epic tackle of a murder suspect from the top of a van on I-75 after having run across several active lanes of traffic. By way of context, police were in pursuit of a vehicle on I-75. The vehicle crosses multiple lanes of traffic without warning several times throughout the video, passes an 18-wheeler truck on the right while maneuvering through the right shoulder, speeds through what appears to be a construction zone, crosses the double white line on entrance and exit ramps, and speeds through residential streets.

It becomes apparent that law enforcement officers are in pursuit when the vehicle comes to a stop and officers follow the driver on foot, dodging vehicles who drivers may be unaware of a foot pursuit in the main lanes of the interstate. The suspect jumps on top of a moving vehicle and an officer follows as the vehicle comes to a rolling stop. The officer makes a tackle off of the top of the vehicle, falling to the ground, where his team awaits and an arrest is made.

The video prompted heavy debate on social media. During that debate, an officer responded, saying, “And that’s the story of how we got the policy for not jumping onto moving cars.” Upon further questioning, the officer clarifies the policy: “An officer shall not place himself or herself in the path of a moving vehicle. Doesn’t say anything about the roof.” The officer in the video doesn’t appear to be injured in this tackle. He accomplishes his goal and is able to obtain control of the suspect without serious harm to himself, his fellow officers or other citizens. Would he have been able to effectively and efficiently accomplish this task any other way than running through high-speed traffic of the multilane interstate highway and then jumping onto the moving vehicle as instigated by the suspect?

Technically, he placed himself in the path of multiple moving vehicles in order to get to the point of standing on top of one of these vehicles. Is the officer disciplined despite his valiant efforts, or did he violate policy despite being successful in accomplishing the goal of obtaining control of the suspect? We would ask further, was the more than 11-minute car chase more or less dangerous than the two-minute foot pursuit and tackle in the path of moving vehicles? This determination is ultimately up to his administration, and clearly involves more complex considerations than simply applying a safety first principle.

Such policies as described above are intended to decrease injury potential among our first responders. They’re also often created for financial and legal security of the greater emergency response system. For the company to prove the responder was not acting within the realm of protocol or policy when the injury occurred, the company may avoid financial or legal responsibility for the consequence. Unfortunately, these policies can be cumbersome to the workforce and may not always be helpful in personnel safety and operational efficacy.

Personal risk tolerance varies widely among individuals. Human error exists whether policy exists or not. In other words, a person’s willingness to take risk exists on a spectrum. Those responders that exist on the far end of the risk-taking spectrum may be seen as a liability to the department, but may be more efficient on a call that requires taking risks to accomplish the end goal successfully. Those responders that exist on the safety-conscious end of the spectrum may be seen as less of a liability to administrators, but may also be less confident in situations that require more risky maneuvers to successfully complete a necessary task. Great risk-taking leads to more opportunity for injury while executing such task.

Only one of the officers from the video jumped onto the moving vehicle, though numerous officers ran through the traffic and surrounded the vehicle. This is an example of first responders responding to the necessary task within their realm of comfort and limits to accomplish a common goal.

Along the same lines, more advanced tactical teams practice and plan for every situation before every high-risk warrant. They even run drills specific to the situation where one of their own goes down. We should take a page from their book, and acknowledge and train to respond to the risks we are likely to face.

Blanket policy can cover up personal safety nets or may distract first responders from their normal routines. Some overreaching blanket policies can eradicate the very purpose of the organization in the first place. For example, Penn State recently banned their Outing Club from going outside. As ludicrous as this may sound, some have speculated that this type of action is predictable after recent legal cases like the Hotchkiss tick case, where a Hotchkiss student was awarded $41 million dollars for an illness sustained by a tick bite while on a school-sponsored outing.

Some personnel don’t know their own limits and may not have as much spatial or temporal awareness as others. These personnel may need individual attention and training, but preaching Safety First as a principle from the beginning of their training and failing to acknowledge inevitable hazards on every scene allows complacency to develop from an early stage of training.

Furthermore, reactionary policy-making may have the unintended consequence of forcing our responders into a position where they must choose between violating a policy, or taking a risk that falls within their personal tolerance and level of skill with the potential to save a life.

Focusing on the Job … and on Having Fun

So if safety is third, what’s first and second?

A more realistic—and more honest—representation of the priorities in an EMS operation puts “getting the job done” first. In reality, EMS providers are always getting their job done in an environment that’s intrinsically unsafe to some degree. Their priority isn’t protecting their safety at all costs, but to complete their job in the safest way possible. If their safety becomes excessively compromised, they’re unable to accomplish the main priority: getting the job done. Formulated this way, one can see how safety plays a role at the very highest priority level, while not itself being the highest sole priority.

This perspective permits us to use the more appropriate language of risk mitigation. What providers are really doing in assessing a scene isn’t determining if it’s “safe” in some black-or-white, absolute way. Instead, the risks that are present are being evaluated, and providers look for ways to reduce those risks, and then balance the mitigated risk against the operational benefits. This is similar to most actions in medicine, where risks and benefits are balanced as an intrinsic and early part of medical decision-making.

Thus, embedded in the rubric of “getting the job done” is evaluating the overall benefit of the job (i.e., we may risk a lot to save a lot), as well exploring ways to reduce that risk to increase the overall chance we can accomplish the job, and be safely put back into operation to accomplish future jobs.

If the risk profile far exceeds its potential for success, the likelihood of not meeting our primary goal (i.e., not getting the job done) is very high. Example: A person is trapped on the second floor of a burning building, and you have no rope and don’t know how to climb. You’re going to try to climb up the building to rescue them. The vast probability is that you’ll fall and hurt yourself, taking yourself out of the operational equation to pursue an action that has a higher likelihood of meeting the primary goal (i.e., getting the job done). So, “safety first” here can be morphed into “safety is a consideration in the ability to get the job done”, which is a much more realistic analysis of our first priorities in EMS. This also explains how safety is still a primary goal of risk analysis and scene management, even if it is not the primary goal of first consideration. The first priority of getting the job done requires, as a subservient value, an analysis of safety.

The second priority in EMS is having fun. This priority might appear cavalier or trivial. But unpacking it speaks to a truly crucial factor in EMS operations.

Looked at one way, “having fun” represents that gut check moment before an EMS action is taken. If you’re no longer having fun or feeling comfortable about an operation, it’s a good opportunity to reassess the top priority: Is this action something that’s sufficiently safe and comes with a high enough benefit to likely result in accomplishing the job?

More deeply and globally, “having fun” questions the underlying assumptions of getting the job done in the first place. Most of us go into EMS because we want to help others in need. Such an activity should be the absolute dream job, and should be intrinsically rewarding for any human being wired for altruism. And yet, this career has remarkably high rates of suicide, divorce and dissatisfaction, along with unhealthy lifestyle decisions and line of duty injuries.

Again, safety plays one role among many here. Perhaps the main point here is mental health and personal resilience. We need to bring back those elements to this work that bring us joy. If we continue deprioritizing joy, ultimately our immediate safety, our relationships, our careers, and even our very own lives may be in jeopardy.

Protecting or retrieving that sense of having fun can also be translated as job satisfaction. Many of us are willing to take substantial risks when the juice is worth the squeeze. In fact, many of us can point to particular high points in our career that represented significant risk, and yet produced a pinnacle moment as an EMS provider. It may be in that sense that risk, consequence and satisfaction in one’s work are linked for an EMS provider. If we exclude those moments that bring us joy because we feel most passionately engaged in the work we do, we may be objectively safer, but at the expense of our professional soul and passion.

Such attention to the passion behind what we do is also important in our educational models. The restriction and regulation of students to prevent them from being put in unsafe situations shouldn’t exclude them from life-changing and career-developing educational opportunities.

The famous mountaineer Willi Unsoeld, pioneer of the first ascent of the West Ridge of Everest and an experiential educator, noted that “risk is at the heart of all education.” He was once asked by a fearful mother if he could guarantee her son’s safety on an outdoor program. No, he told her, he could only guarantee exposure to risk. But, he added, that by sheltering her son from risk, the mother would be guaranteeing the death of her son’s soul.

Princeton University’s Rick Curtis encapsulates this balance as R+ and R-. R+ is the “gain” accrued from accepting risk, while R- is the “loss” possible from accepting risk.8 So, if a preceptor asks a class for a volunteer for someone to demonstrate testing blood sugar in a patient, the R- risk arguing against a student stepping forward is that they’ll be shamed in front of the class if they get it wrong, or they may develop fear responses to testing blood sugar. The R+ benefit is that they’ll get to practice this skill under duress situations, and will receive potentially beneficial critiques from the instructor, as well as earn participation credits during the class. Surely the “safest” approach is not to volunteer, privileging R-. But the educationally most beneficial approach might be volunteering, privileging R+. This is where the joy comes in.

If we create environments where participatory learning is encouraged and is enjoyable for the student, it promotes participatory careers, and models the concept that a main reason why we do this work is that it should be fun—meaning it should be rewarding, sustainable,= and balance the R+ benefits of risk along with risk’s R- dangers. Training our students and younger EMS personnel to be seeking the R+ benefits of risk for its own sake models for them a practice style that facilitates lifelong learning, engagement with their patients and peers, and a zest for seeking out the parameters of this work that are sustainable and rewarding.

By contrast, teaching students and younger EMS personnel to squash joy in favor of safety, and to never unnecessarily put themselves, their reputations, or their careers at risk, may be defensible in our increasingly litigious society, but wreaks irreparable damage to our industry as a whole.

To paraphrase the words of Unsoeld, valuing risk prevention and fear over the joy of taking risks in the interest of saving lives will indeed ensure that safety is first; but it will also guarantee the death of the very soul of EMS.

The available evidence supports this emphasis on excitement, engagement and yes, “fun,” in professional training and practice. Studies suggest what’s also intuitively believable: people who enjoy the work they do, do that work better.9,10 In this sense, the second priority of having fun reinforces the first priority of getting the job done, in the same way that the third priority of safety reinforces both priorities.

Once job completion and fun in doing so are addressed, safety becomes a consideration in its own right. However, it should be clear from the preceding discussion that safety undergirds both the first and second priority as a necessary consideration (i.e., mitigating risk) and factor (i.e., providing R+ benefit as well as R- danger).

Indeed, the operational priorities in EMS can be conceived as a pyramid. Getting the job done is the narrowest and most important value, but it’s significantly supported by a much larger culture and practice supporting fun, sustainable, satisfaction-generating work that mitigates risk and considers safety. These two values are both supported by a sophisticated understanding of safety and its role in supporting these higher two values.           

Conclusion

In educational opportunities, train like you plan to fight. Since there may not be an actual patient, the “benefit” in the risk-benefit analysis may be lesser. However, taking no risks in training ensures you’ll be less prepared to take risks—even R+ risks—in actual operations. For example, you don’t stop patient care because it’s raining, so don’t stop your training simply because it’s raining.

Also, during your education, fight the idea that we can ever say “the scene is safe.” Accept that our work is done in an imperfect environment where safety cannot be ensured. Then, recognize that your educational task, to promote the idea that your work needs to be accomplished and needs to be fun and sustainable, is to learn ways to mitigate risk that promote mission completion and professional sustainability.

In real-world operations, understand the end goal. Know what’s needed to complete that task, and how risk can be engaged to mitigate R- risk danger and to enhance R+ risk benefit.

Learn the ways you respond to risk and build personal adaptations, rather than simply assuming you should avoid risk at all costs. This is especially important for psychological triggers or responses you may recognize in yourself. Fear-based action is a poor driver of exceptional EMS performance. Stay vigilant throughout your operational period.

Another problem with training personnel to check “scene safety” as a first step and priority is ignoring the fact that scenes, and their safety parameters, evolve. Rather than using safety as a first priority, use it as an undergirding factor to all elements of the operation, and consider it to be a parameter that’s dynamic and can change as the operation evolves.

In retrospective incident analysis, understand that accidents and unfortunate incidents occur. In building risk management strategies around incident analysis, query whether the incident could happen again, if it’s preventable through actions that don’t threaten the first or second priority but improve the safety profile, and what that prevention technique would be. Remember that policies only go so far in managing risk. Often, personal knowledge and a personal understanding of limitations is far more effective than a corporate policy in balancing operational effectiveness and safety.

We hope that a Safety Third movement sparks an industry-wide dialogue about where we draw the line in creating policy around safety versus other values, and how we promote effective, sustainable and safe EMS operations. Such dialogue will require an honest conversation about what our collective risk tolerance is, understanding that accidents and incidents will happen. If we simply apply a Safety First model, we’ll never be able to meaningfully engage that dialogue.

Finally, we feel pretty certain that a sophisticated operational analysis around risk will reveal both the reality that risk is intrinsic and potentially functional, and that the most effective interventions to manage it are applied at the individual decision-making level and not at the corporate policy level.

It may very well be that a future where safety is third is one that’s more effective, more fun and sustainable, and one that’s more safe overall, both for healthcare providers and for the patients they serve.

Disaster Podcast: Is Safety Really First for Responders?
The authors of this article appeared on the Disaster Podcast on Dec. 27, 2018, to discuss the concept of Safety Third.

References

1. Hawkins SC: Wilderness EMS systems. In Hawkins SC (Ed.), Wilderness EMS. Philadelphia: Wolters Kluwer: Philadelphia, 2018.

2. Rowe M. (Aug. 11, 2014.) Off the wall: Safety third conversation continues. Mike Rowe. Retrieved Oct. 21, 2017, from  www.mikerowe.com/2014/08/off-the-wall-safety-third-conversation-continues.

3. Rowe M, Barsky DM, Bradley A. (Nov. 24, 2009.) Dirty Jobs. Season 5, Episode 18: Safety third. Retrieved Sep. 29, 2018, from www.amazon.com/Dirty-Jobs-Season-5/dp/B004P2SHA4.

4. Kochanek KD, Murphy SL, Xu J, et al. Deaths: Final data for 2014. National Vital Statistics Reports. 2016;65(4). Retrieved Sept. 29, 2018, from www.cdc.gov/nchs/data/nvsr/nvsr65/nvsr65_04.pdf.

5. National Institute for Occupational Safety and Health. (Aug. 7, 2017.) Emergency medical services workers: How employers can prevent injuries and exposures. Centers for Disease Control and Prevention. Retrieved Sept. 29, 2019, from www.cdc.gov/niosh/docs/2017-194/default.html.

6. Reason J. Human error. Cambridge University Press: Cambridge, U.K., 1990.

7. Lieberman J. (March 21, 2016.) What do Doug Tompkins, the Swiss Cheese Model, and “PEEPS” have in common? Wilderness Medicine Magazine. Retrieved Oct. 21, 2017, from www.wms.org/magazine/1178/The-Swiss-Cheese-Model.

8. Neill J. (Dec. 16, 2003.) The Concept of risk: Perceptions of the likelihood of loss (R-) or gain (R+). Wilderdom. Retrieved Sept. 29, 2018, from www.wilderdom.com/risk/RiskConcept.html.

9. Wright TA, Cropanzano R. Psychological well-being and job satisfaction as predictors of job performance. J Occup Health Psychol. 2000;5(1):84–94.

10. Zelenski JM, Murphy SA, Jenkins DA. The happy-productive worker thesis revisited. Journal of Happiness Studies. 2008;9(4):521–537.