Incident Prevention Magazine

Those of us in the industry tasked with record-keeping sometimes struggle with all of the different reporting scenarios. OSHA 29 CFR 1904, “Recording and Reporting Occupational Injuries and Illness,” gives us guidelines, but even the most thorough research of compliance requirements can still lead to questions and confusion.

For example, workers’ compensation cases may not be recordable as OSHA cases due to exceptions in the agency’s record-keeping rules. Workers’ compensation is mandated by each state, while OSHA 1904 is a federal record-keeping standard.

Further, OSHA’s record-keeping standard was updated in 2002, at which time many changes were made, including some that made the standard easier to understand but others that made it more difficult. Additional changes were made effective January 1, 2015. While basic reporting has essentially remained the same over the years, it’s important to be aware of the 2015 change found at 1904.39(a)(2), which states, “Within twenty-four (24) hours after the in-patient hospitalization of one or more employees or an employee's amputation or an employee's loss of an eye, as a result of a work-related incident, you must report the in-patient hospitalization, amputation, or loss of an eye to OSHA.” These requirements were added to provide OSHA insight on less serious injuries in certain industries that typically have a higher incident/DART rate.

The electric utility industry is experiencing more major catastrophic storms than ever. Hurricanes, tornadoes, and snow and ice storms are taking their toll on both systems and employees. It was just several months ago that we were dealing with back-to-back hurricanes – Florence and Michael – and now we’re well into a winter that has dealt large swaths of the country plenty of snow and record-breaking low temperatures. 

At some point I stopped counting the number of storms I have worked during my 51 years in the industry. What I do know is that each storm has been a learning experience for me. One thing I’ve noticed over time – in addition to the increase in the number and severity of natural disasters – is that mutual assistance from other utilities and contractors has become a significant resource for host utilities that have suffered damage from these events. In light of that, I want to share some information that may help things go more smoothly for you and your crews during future restoration efforts.

I would like to ask those of you reading this article to reflect on your professional life in 2018. What was different from previous years? Was safety at your company better, worse or about the same? As I sit and write this article during the first week of October 2018, I know that so far this year, the electric utility industry has suffered more than 20 fatal accidents and over 30 serious flashes and contacts. I don’t know what’s going to happen between now and the end of the year, but I pray no one else gets hurt.

The fact is, our industry has suffered extremely high numbers of fatalities since around 2013. The last I heard, in 2017 we had 45 fatalities between investor-owned utilities, cooperatives, contractors and municipals. NIOSH and EPRI started doing research in the mid-1990s through approximately 2006, and they found that the electric utility industry recorded 24 to 28 fatalities each year. The causes of those fatalities included contacts, falls and vehicle accidents.

What continues to amaze me is that our industry has the investigation and root cause analysis measures to identify why accidents keep happening, but we fail to implement the measures available to us to prevent recurrences of these types of accidents. The majority of fatalities occur during energized line work, yet they keep happening. Why? On one hand, while it’s true that lineworkers are some of the best trained craft workers out there, even the most seasoned lineman is human and can make an error in a moment of stress, or if his mind wanders or for any number of other reasons. 

2018 is turning out to be a devastating year in our industry. The frequency of energized contacts, flashes, severe injuries and fatalities continues to increase. Why – in a professional trade that requires such an extensive amount of apprenticeship time – do lineworkers have such high incident and accident rates?

In this installment of “Voice of Experience,” I want to review two accidents I am familiar with so that we can dive into why they happened, and how you can prevent them from happening on your job sites.

The First Accident
In the first accident, a journeyman lineman lost his right arm to the shoulder. The immediate cause was a 7.2-kV electrical contact phase to ground.

The day of the accident, the journeyman was running a little late, so he drove his personal vehicle to the job site to avoid losing more time. An apprentice lineman had driven a bucket truck to the job site for the journeyman to use. All employees gathered to discuss the job plan. The job, which had been in progress for several days, was reconductoring approximately 5,000 feet of an existing three-phase 12.4-kV line from #2 ACSR to 397 MCM. New poles were set, and old conductors were spread on layout arms. The new conductors had been pulled in and sagged to tension the day before. The day the accident occurred, there was discussion during the job briefing about moving the new conductors from roller blocks and tying them in on the new insulators with preform ties. The structure where the incident occurred was a 45-foot Class 3 with a 10-foot wood arm. Insulated layout arms were mounted on the ends of arms. The middle and field-side phases were set to the field side of the arm. The existing energized road-side phase was on a short arm set to the road side of the pole. All three of the old phases were still energized. The new conductors had system safety grounds installed on each end, as required by standards.

Many recent articles I have read in other magazines and via social media emphasize the importance of worker training. I couldn’t agree more. It is both important and valuable that employers invest in training for new employees entering the industry as well as current employees. While the return on investment cannot always be accurately measured and calculated, the ROI does exist nonetheless – just imagine what injury and fatality statistics would look like if we did not train our workers.

One of an employer’s training-related responsibilities is to investigate cases of failure to follow training that result in property damage, injuries or fatalities. OSHA also obligates employers to report any accident that requires medical attention beyond first aid, if the accident is work-related. And risk management professionals and certified loss control professionals are required to investigate property damage involving employees for insurance purposes. Loss control can be difficult to track because damage is not always immediate, and the cost of damages may not be directly attributable to failure to use proper training. In addition, a bad underground splice or a failed connection on primary or secondary that results in property damage may or may not be recorded by an employer as a failure to use proper training.

I understand that we are human beings, and because we are human, we make mistakes. And yet, I would like for all of us to think about the possibility of following all rules and regulations all the time – in short, I want all of us to strive to operate excellently. By adhering to what we learn in our training and using the correct procedures to perform our work, we can protect lives and prevent property damage.

It has taken the electric utility industry many years to understand induced voltage. When I started working in the 1960s, it was explained to me that voltage remaining on de-energized lines was static voltage that had to be bled off or else it could be deadly. Now, when I speak to groups about temporary system grounding for the protection of employees, I occasionally still hear the term “static voltage” being used to describe what really is induced voltage from a nearby energized line. Even today, not everyone in the industry completely understands induced voltage.

So, what exactly is induced voltage? Here are some things utility safety and operations professionals should understand. The electromagnetic field around an energized conductor produces capacitive and magnetic coupling to all nearby objects within the electromagnetic field. The voltage level of the energized conductor and the physical length of the de-energized conductor that is exposed to the energized (source) conductor will determine the amount of voltage on the de-energized conductor or equipment. A de-energized conductor or piece of equipment will remain energized as long as the source remains energized and de-energized equipment remains ungrounded. Properly installed temporary system safety grounds can be used to create an equipotential work zone for employees.

The induced voltage found on de-energized equipment is not static, and it can’t be bled off. System safety grounds that have been installed simply give the induced voltage a conductive connection to ground. Once grounds are removed, the induced voltage returns to exactly the same amount of voltage instantly. It is voltage of 60 cycles per second in a steady-state condition, because there is no path in which electricity can flow other than the energized, isolated conductor or equipment. If grounds are applied to de-energized conductors, the voltage immediately will collapse to near zero, but now the physics have changed and a current flow is established in the system safety grounds. The amount of current flow in ground sets is determined by the amount of induced voltage on the de-energized equipment before the grounds were installed, and the resistance of the ground set and the ground. In addition, the more ground sets that are applied to a de-energized line, the less current flow there is in each set of grounds.

In today’s electric utility environment, there are many training demands and opportunities due to new and inexperienced employees entering the workforce as older, more experienced workers continue to retire. New employees entering the field require – and are hungry for – information and hands-on experience, and they’re excited by the chance to engage in line work. To rubber-glove energized primaries and perform bare-hand transmission work is fascinating to younger workers and often provides them with an indescribable level of satisfaction and accomplishment. Ours is an exciting occupation, to say the least.

And yet ours also is an occupation that can be riddled with hazards. That’s why all of our employees must be given a strong foundation of skills training for their own protection. In our industry, many consider basic line skills training to be the most important type of training workers can receive, and I agree.

Considering recent annual accident totals reported by the U.S. Bureau of Labor Statistics, there is great reason for employers to be vigilant about the training of their workers. The electric utility industry suffered more than 40 fatalities in 2017 alone. Some of those deaths occurred because of falls and vehicle accidents, but a great number more occurred when an unprotected part of a worker’s body made contact with an energized conductor or piece of equipment. Phase-to-ground contacts that resulted in severe burns also were reported about once per week. These types of incidents are almost always preventable, so why do they continue to occur? Does it have something to do with training or human performance? Is there something else going on? 

In light of some recent incidents in the electric utility industry, numerous root cause investigations have been conducted to determine why those events occurred. The frequency of the events and their similarities are alarming. Some of the more recent cases involved induced voltages from nearby energized lines to de-energized lines and equipment. In one instance, an employee opened a system safety ground and got in series with ungrounded and grounded equipment and conductors, which resulted in severe burns to the employee. Another incident involved an uninsulated boom truck contacting primary conductors. The truck was not grounded or barricaded, and the event resulted in one fatality and one severe injury.

When all the final numbers are tallied, 2017 may wind up being one of the more devastating years in the electric utility industry’s recent past. So, why is our industry suffering the same types of incidents today as in previous decades? There are many contributing factors associated with each event. Among those named in many incident-related reports – including reports on the incidents I referred to in the previous paragraph – is human error. Some have even said human error is the root cause of some of these events, but I don’t agree. There typically is a more direct root cause of an incident than any mistakes made by employees.  

Human Error and Normalization of Deviation
Before we go any further, let’s review what is meant by the term “human error.” If you search online, you’ll come up with a variety of sources that define the term, but to put it briefly, human error is an individual’s deviation from intention, expectation or desirability.

Speaking of deviation, one related phenomenon that is suspected of playing a role in many incidents is normalization of deviation. This occurs when humans become used to, for instance, executing a task in such a way that does not meet defined performance standards; over time, however, even though this inferior execution does not meet the standards, it nonetheless becomes an accepted practice. When this behavior is endorsed by others, some may recognize it as poor or unacceptable performance, but they may not feel comfortable intervening, or they may not be permitted to intervene.

I travel frequently for work, and everywhere I go, I hear conversations about injuries and accidents that have occurred in the electric utility industry. Many of those conversations have included comments about how dangerous or hazardous our industry is. And in several articles published on Forbes.com based on data from the U.S. Bureau of Labor Statistics, the job title of electrical power-line installer and repairer is consistently listed as one of the 10 deadliest occupations in America.

What is helping to keep this title listed as one of the deadliest jobs in the country? Many of us who have worked in the industry for years agree on a theory that it’s the people who are changing – not the job itself. The equipment we use has advanced and improved over time, and now it’s safer than ever before; however, the number of workers in the industry also has increased over the past 10 years.

A project led by the Electric Power Research Institute – known as the Occupational Health and Safety Database program – “enables the electric energy industry to monitor annual injury/illness trends, perform benchmarking, evaluate intervention programs, and investigate occupational health and safety research,” according to the institute’s “Occupational Health and Safety Annual Report 2008” (see www.epri.com/#/pages/product/1015630/). In the 2008 report, 13 years of personnel, injury and claims data – from 1995 through 2007 – from 17 utilities was integrated into a single data system. Findings in that report include the following:

• More than 60 percent of employees were between 41 to 60 years old. Nearly 35 percent were in the 41-50 age group.
• Workers aged 21-30 – approximately 10 percent of workers – had the highest observed injury rate.
• Lineworkers, mechanics and meter readers had the greatest proportions of injuries among electrical energy occupational groups; these three types of workers also had among the highest injury rates.

Over the next few installments of “Voice of Experience,” I’ll be reviewing some accidents that have taken place in the electric utility industry. I’ve had many requests for information about incident investigations and would like to share some details in hopes of preventing similar accidents in the future. Distribution cover-up will be the focus for this issue’s column.

Approximately half – or even more – of accidents that result in flashes and electrical contacts are the result of poor cover-up or total lack of rated protective cover. Why would a lineworker not take the time to install protective cover that would assure a safe work area? According to statistics and accident reports, the industry suffers an average of one contact or flash every week. That needs to stop.

Investigations into many accidents, some of which involved fatal contact with system or source voltages, have revealed that failure to cover up all differences of potential in the immediate work area was the common denominator in most flashes and contacts. If you are or your company is following the minimum requirements found in OSHA 29 CFR 1910.269(l), “Working on or near exposed energized parts,” it is simply not enough to ensure an employee is totally protected from differences of potential in the work area.

The human body essentially is a 1,000-ohm resistor in an electrical circuit. When a lineworker fails to cover energized parts as well as differences of potential in the immediate work area, as little as a 50-volt AC electrical source may enter the body. If the current path crosses the heart, as few as 40 to 50 milliamps can induce atrial fibrillation, cause the heart to stop sinus rhythm and electrocute the worker. The industry is quite familiar with medium-voltage contacts but many times lacks respect for low-voltage contacts that can be just as fatal.

Lately there has been a rash of incidents involving flashes and contacts with primary voltage. The incidents occurred due to improperly written switching orders or missed switching steps, none of which were recognized by the workers involved with the tasks. These types of errors have long been a problem and continue to result in numerous injuries and fatalities.  

In April 2014, OSHA’s revised 29 CFR 1910.269 standard was published. This was the first revision to the standard in 20 years, and one paragraph in particular that was clarified was paragraph (m), “Deenergizing lines and equipment for employee protection,” which addresses system operations. As of the OSHA update, the employer is now obligated to appoint an employee to be in charge of the clearance issued by the system operator; this employee will have control over and oversight of all switching that affects the performance of the system.  

Specifically, OSHA has promulgated the following rules.  

1910.269(m)(2)(i)
If a system operator is in charge of the lines or equipment and their means of disconnection, the employer shall designate one employee in the crew to be in charge of the clearance and shall comply with all of the requirements of paragraph (m)(3) of this section in the order specified. 

1910.269(m)(3)(ii)
The employer shall ensure that all switches, disconnectors, jumpers, taps, and other means through which known sources of electric energy may be supplied to the particular lines and equipment to be deenergized are open. The employer shall render such means inoperable, unless its design does not so permit, and then ensure that such means are tagged to indicate that employees are at work. 

Electric utilities must establish a clearance – also referred to as an “open air gap” – on all known sources of the system and source voltages. A clearance also should be used to disable all automatic switchgear to ensure that all system voltage has been isolated from the work area. This procedure is regulatory language and required to protect employees. Tags shall be applied to all open points to indicate that employees are at work and nothing shall be re-energized.

The revised OSHA 29 CFR 1910.269 standard has now been in place for three years. In making the revisions, OSHA replaced older, passive language that left much to be understood with more objective language that clarifies the meaning and intent of the regulation. The standard is now easier to understand and sets the expectations for employers and employees.

There were some major changes made to the standard, as we all know. Several more subtle changes also were included and have been discussed much less, but they still have had a significant impact on the regulation. In this installment of “Voice of Experience,” I want to focus on one of these more subtle changes that I believe has a tremendous effect on the training requirements found in 1910.269(a)(2). The 1910.269 standard published in 1994 was straightforward, describing what was required in order for an employer to determine that an employee was a qualified worker. By and large, the industry believed that if an employee had the required training, he or she could be determined to be qualified. Now, per paragraph 1910.269(a)(2) of the revised 2014 standard, all employees performing work covered by the section shall be trained as follows:
• Each employee shall be trained in, and familiar with, the safety-related work practices, safety procedures, and other safety requirements in this section that pertain to his or her job assignments. (1910.269(a)(2)(i)(A))
• Each employee shall also be trained in and familiar with any other safety practices, including applicable emergency procedures (such as pole-top and manhole rescue), that are not specifically addressed by this section but that are related to his or her work and are necessary for his or her safety. (1910.269(a)(2)(i)(B))
• The degree of training shall be determined by the risk to the employee for the hazard involved. (1910.269(a)(2)(i)(C))

OSHA record-keeping has long been an administrative challenge to businesses required to keep OSHA logs. In this installment of “Voice of Experience,” I’ll cover some changes that have occurred over the years as well as some essentials that all employers and employees must understand in order to maintain compliance with OSHA requirements.

When the change from the OSHA 200 log to electronic record-keeping was made in 2002, it was a relief to many. At that time, all issues involving first aid were resolved; a list of first aid treatments was identified and took any doubt out of the requirement to report medical attention beyond first aid.

The addition of a hearing loss column to OSHA’s Form 300, “Log of Work-Related Injuries and Illnesses,” in 2004 helped identify hearing loss for those businesses covered by OSHA 29 CFR 1910.95(c), “Hearing conservation program.” Previously, hearing loss often was considered an illness rather than an injury.

Today, the number of logs a business must maintain is determined by the number of premises operated by the business. A log is required to be maintained for each location with an address unless there are multiple facilities at the same address. Centralized electronic record-keeping is acceptable if the records can be provided within four business hours upon request by an OSHA officer. The request must be made in the location of the corporate office where records are kept, even when it is in a different time zone.

An injury must be reported to a record-keeper for logging within a maximum of seven days from the time of the accident; this requirement has not changed. The supporting forms required to document the log entry also remain the same. OSHA’s Form 301, “Injury and Illness Incident Report,” or an acceptable state workers’ compensation form must accompany any orders written by a licensed health care provider (LHCP). All documentation must be retained and kept available in case of an audit. The number of days away or restricted days must be recorded and may be capped at 180 days. The current year and the last five years of OSHA 300 logs must be available for audit or inspection upon request by approved officials. OSHA’s Form 300A, “Summary of Work-Related Injuries and Illnesses,” must be posted no later than February 1 of the year following the year covered by the form, and it must remain posted in the establishment for 90 days in conspicuous locations that are frequented by employees.

OSHA 29 CFR 1910.67 is the performance-based standard that covers requirements when using vehicle-mounted elevating and rotating work platforms, including the bucket trucks we use in the electric utility industry. There are many types of buckets, and the task to be performed will determine what type of bucket is required. This standard even covers noninsulated work platforms, sometimes referred to as JLGs, used in civil construction. For clarification, a mobile platform covered under 1910.68, “Manlifts,” is not covered under the 1910.67 standard. Mobile platforms are considered mobile scaffolding and require standard guardrail protection. Additional fall restraint normally is employed depending on the type of work and availability of fall protection attachment points.

Although today our industry is better trained than ever, it wasn’t so long ago that one of the most violated standards was the requirement to fly the booms every day before employee use. According to paragraph 1910.67(c)(2)(i), “Lift controls shall be tested each day prior to use to determine that such controls are in safe working condition.”

The fall protection requirements for utility bucket trucks are currently covered under 1910.269(g), “Personal protective equipment.” The users of bucket trucks now have options for fall protection, including a personal fall arrest system, fall prevention or a retractable lanyard. Fall protection equipment is much more user-friendly and lightweight than ever before.

In the remainder of this article, I want to focus on bucket truck inspections and maintenance required by OSHA, manufacturers and others. This information is critical but sometimes is not followed by employers or employees, which has led to a number of catastrophes.

I was recently asked to provide information about the challenges and opportunities found when working on direct-buried underground distribution (UD) systems. In light of that request, I’ll address those topics in this installment of “Voice of Experience.”

My first opportunity to work on UD systems was as a truck driver operating a trencher in the late 1960s. UD systems were fairly new at the time; lineworkers were learning new techniques, using different types of tools to terminate cables and installing switchable elbows. In that day, some elbows were non-load-break. Back then the work was all about proper use of tools, identifying equipment and following the minimum rules. There were no OSHA regulations. We learned many techniques and work practices the old-fashioned way: through the school of hard knocks.

The challenges that workers faced back then are much the same as they are today, with two exceptions: The industry has more experience installing and operating UD systems, and equipment is now much more technically sophisticated and reliable. For many years, maintenance of UD systems was nonexistent. The common approach was to dig a ditch and put cable in the ground, and industry workers believed everything would last forever. That belief was short-lived; within a few years, external concentric neutrals began oxidizing, and radial and loop-fed systems suddenly became single-conductor, earthen-ground return systems. Driven ground rods at transformers split coil for secondary voltages. There was no neutral conductor for return currents or fault current flow.

In the 2014 OSHA update to 29 CFR 1910.269 and 1926 Subpart V, major changes were made regarding apparel and minimum approach distance (MAD) calculations. And yet I believe the agency missed an opportunity related to distribution voltages and gloving of energized conductors and equipment. For all intents and purposes, other than the MAD updates, few changes occurred in 29 CFR 1910.269(l) regarding working position. A new requirement removed any implied obligation that an employer is accountable for ensuring employees do not approach or take any conductive objects within the MADs found in tables 6 to 10 of 1910.269. The standard now clearly and without any doubt requires an employer to calculate and provide MADs to all employees and contractors working on energized systems.

Paragraph 1910.269(l)(3)(i) now states that the “employer shall establish minimum approach distances no less than the distances computed by Table R-3 for ac systems or Table R-8 for dc systems.” And the updated standard also now requires an engineering analysis on voltages greater than 72.5 kV to allow for transient overvoltages that occur due to system operations, breakers, capacitors or lightning. Ironically, the MAD found in the 2002 National Electrical Safety Code for 25-kV systems was 31 inches, 12 years before it was changed in OSHA’s update to 1910.269.

When OSHA updated 29 CFR 1910.269 and merged almost all of its requirements with 1926 Subpart V, the requirement to protect employees from step potential was enhanced. In the months following the publication of the final rule, this change was rarely mentioned in the major webinars conducted by several prominent utility industry groups, so I want to take this opportunity to cover what you need to know.

First, let’s talk a bit about the basic fundamentals of Ohm’s law and Kirchoff’s law of current division in order to ensure you understand the seriousness of step potential hazards. Ohm’s law states that electricity will take any and all conductive paths, and Kirchoff’s law of current division states that the amount of current flow is dependent on the resistance and impedance in the current path.

As I travel around and conduct training, I find that many electric utility employees – much like me in the 1970s – do not understand these and other basic laws of physics that determine the number of hazards we face. The human body is not much more than a 1,000-ohm resistor when put into an electrical circuit. If a human body is placed in an electrical path/circuit, the amount of electricity that enters the body is about 50 volts AC. During this type of occurrence, the soles of normal work boots and shoes will provide an employee a small amount of protection, but if the employee were to kneel down and touch a vehicle grounded to a system neutral, or place a hand on a grounded object, the amount of protection would be significantly reduced.

Last May, OSHA published its final rule regarding confined spaces in construction. Since that time, there have been many questions about the differences between the new construction standard and 29 CFR 1910.146, “Permit-required confined spaces.” In this installment of “Voice of Experience,” we will take a closer look at both standards in an effort to clear up any remaining confusion.

“Confined Spaces in Construction” is the title of 1926 Subpart AA, the recently released construction standard. Before Subpart AA was published, 1910.146 was the only OSHA standard that addressed permit-required confined spaces, and 1910.146 assumes that the host employer and the controlling employer are one and the same. But over time OSHA realized that because construction activities may involve more than one employer on a job site – which is not usually the case with general industry jobs – the controlling employer is not always the host employer. In fact, there may be a variety of contractors working on or in a space, building the space or entering the space. There was clearly a need for these issues to be addressed by OSHA, and the agency has now done so in 1926 Subpart AA.

Given the subject matter of the new construction standard and 1910.146, it is no surprise that there are a number of similarities between the two. However, Subpart AA is much more detailed than 1910.146. This is particularly apparent in 1926.1209, “Duties of attendants,” and 1926.1210, “Duties of entry supervisors,” which explicitly address accountability and responsibility for protection of workers on job sites.

OSHA fines will increase for the first time in 25 years under a provision in the recently signed U.S. congressional budget deal.

The Federal Civil Penalties Inflation Adjustment Act of 1990 exempted OSHA from increasing its penalties to keep pace with inflation. But a section of the new budget signed in November by President Barack Obama – referred to as the Federal Civil Penalties Inflation Adjustment Act Improvements Act of 2015 – strikes the 1990 exemption.

Now, OSHA is directed to issue an interim final rule adjusting its penalties to account for current inflation levels, which would raise proposed fines by about 80 percent. This means the maximum penalty for a willful violation would rise from the current $70,000 to about $127,000. Additionally, OSHA fines for serious and other-than-serious violations could increase from $7,000 per violation to approximately $13,000 per violation. The penalty adjustment must take effect before August 1 of this year. In subsequent years, employers should expect to see OSHA fines increase by January 15 of each year as the agency makes adjustments based on the annual percentage increase in the consumer price index.

With the recent changes to the OSHA standard, many employers are working on what rules apply – the arc flash standard or the PPE standard – and how to comply with them. Part of the issue is determining how many types of protection are needed and what types of protection are appropriate.

To begin, OSHA’s requirements for all personal protective equipment can be found in 29 CFR 1910 Subpart I. Rules specific to hand protection can be found in 1910.138. They read as follows:

1910.138(a)
“General requirements. Employers shall select and require employees to use appropriate hand protection when employees' hands are exposed to hazards such as those from skin absorption of harmful substances; severe cuts or lacerations; severe abrasions; punctures; chemical burns; thermal burns; and harmful temperature extremes.”