This blog presents Metropolitan Engineering Consulting & Forensics (MEC&F) claim management and claim investigation analyses of some of the typical claims we handle
The driver of a silver Land Rover SUV was aggressively switching traffic on and off.
Capt. Doug Young of the California Highway Patrol said that just after 5
a.m., a double-tanker fuel truck ended up hitting the center divider
and then overturning, with the front tank bursting into flames.
The burned front tank and the SUV it collided with rested in the carpool
lane. The second tank, which also overturned, was still intact, but
blocking the two left lanes.
The victims were the drivers of each vehicle. Neither had been identified by authorities as of late Friday.
Friday, August 24, 2018 HAWTHORNE, Calif. (KABC) --
Two drivers were killed Friday morning in a crash involving a tanker truck and an SUV on the 105 Freeway in Hawthorne, authorities said.
Firefighters doused massive flames in the aftermath of the wreck, which happened about 5:13 a.m. and prompted the shutdown of all lanes near Prairie Avenue, the California Highway Patrol said.
The CHP did not comment on the cause of the crash, but witnesses pointed the finger on the driver of a silver Land Rover who was aggressively swerving in and out of traffic.
According to the Los Angeles County Fire Department, the driver of the Land Rover and the driver in the tanker truck died at the scene. They were not immediately identified.
The SUV "jumped up a little bit and lost control because his car was tilted -- so swerving to the left," the witness said. "And there was a tanker with a truck driver. The truck started to make a scissor -- the tanker itself detached itself.
"The silver Land Rover crashed into the divider," he said.
More than an hour after the collision, the blaze remained active as firefighters apparently decided to allow it to burn itself out. By the afternoon, what was left of the two vehicles: a tangle of scorched metal.
Freeway traffic was at a standstill for hours at the crash site, located about 3 miles east of Los Angeles International Airport.
Several travelers were seen abandoning vehicles that had been headed for LAX. With suitcases in tow, they walked off the freeway in an effort to catch their flights. Strangers helped one another by carrying their bags over the fence.
Others patronized a food truck owned by AC Catering, which opened for business in the middle of a westbound lane.
"We're hoping to get out, to get the plane, but it looks like we're not going to catch our plane," said stranded traveler Felipe Alvarado. "So now we're just here waiting, patiently, like everyone else. We ain't got no choice."
The eastbound side was reopened shortly after 8 a.m. After several hours, CalTrans officials said the structural integrity of the freeway was inspected and only minor damage to the surface was found.
Westbound lanes were reopened a little after 7 p.m..
The Metro Green Line service was also shut down between the Hawthorne/Lennox station and the Vermont/Athens station because of damage from the fiery wreck.
Construction
workers ruptured a natural gas line at the corner of Milwaukee and
Campbell on Aug. 24, 2018. Two workers were burned. (Credit: CBS)
Fire breaks out after construction crew hits gas line in Logan Square August 24, 2018
by Gaynor Hall
CHICAGO, IL —
Emergency crews responded to a fire in Logan Square on Friday afternoon.
Construction workers hit a gas line while working in the 2000 block of North Milwaukee Avenue. Two workers were hurt, but their injuries were not severe.
Fire officials designated the scene Level 1 Hazmat.
============================
CHICAGO, IL (CBS) —
Two construction workers were burned Friday afternoon when they struck a natural gas line, sparking a fire in the Logan Square neighborhood.
The Chicago Fire Department initiated a hazardous materials response after the workers ruptured a gas line on the 2000 block of North Milwaukee Avenue shortly before 1 p.m.
A construction crew working in a vacant lot struck a gas line, and two of the workers were burned when the gas ignited.
One worker was taken to Stroger Hospital, the other was taken to Presence Saints Mary and Elizabeth Medical Center. Both suffered minor burns, according to a Fire Department spokesperson.
Hurricane Lane Is Downgraded to Tropical Storm, but Hawaii Prepares for Flooding
As Hurricane Lane inched toward Hawaii on Friday, its outer bands bringing landslides, floods and power failures to parts of the archipelago, the mayor of Maui found himself hoping for the last thing he expected to want this weekend: rain.
Three fires had broken out in West Maui, he said, possibly caused by downed power lines and likely stoked by the whipping winds. By the afternoon, two fires were completely contained but still burning, and the third, affecting about 1,500 acres, was about 40 percent contained.
“We were expecting flooding, high winds, big surf — we weren’t expecting very little rain, heavy winds and a big fire,” the mayor, Alan Arakawa, said. “We’re hoping for just enough rain to put out the fires, not enough rain to have mudslides after that.”
But officials caught a break amid the chaos: By late afternoon, the National Weather Service downgraded Lane to a tropical storm, an intense downshift from the Category 3 hurricane it was just 24 hours earlier.
The storm, which was traveling only a few miles per hour, was expected to continue weakening. But the agency warned that the tropical storm would continue to pose a risk for flooding and could still hurl winds of up to 70 m.p.h. Photo Fires in Kaanapali, Maui. Credit Social Media/Reuters
“We dodged a bullet,” Mayor Kirk Caldwell of Honolulu said at a news conference. But he added that “doesn’t mean it’s over.”
“We’re going to have rain and wind and local flooding — and we need to be vigilant,” he said.
Between the storm’s lumbering speed and Hawaii’s countless microclimates, it was difficult to predict would happen throughout the day Friday. Forecasters warned that the storm was still dangerous, and island residents and visitors, surrounded by thousands of miles of ocean, were mostly stuck to watch and wait.
“You go to higher ground, hunker down with stored water and canned food, because there’s nowhere else to escape,” said Ron Matayoshi, a volunteer at the McKinley High School emergency evacuation center in urban Honolulu.
Gov. David Ige said he had received a phone call on Friday from President Trump, who pledged the support of federal agencies to help the state. Hurricane Lane Map: Tracking the Storm’s Path Toward Hawaii
By Friday morning, Hurricane Lane had weakened to a Category 2 storm, but the storm continued to dump heavy rainfall on parts of Hawaii.
Forecasters expected the storm to keep moving north before making a westward turn on Saturday, and it was expected to past close to the central islands by Friday night.
Alison Nugent, an assistant professor of atmospheric sciences at the University of Hawaii at Manoa, said the storm was losing strength as the wind shear, which typically weakens hurricanes before they get to Hawaii, finally showed up.
But even a weak hurricane could be unpredictable and destructive, Professor Nugent explained, because of the way storms interact with Hawaii’s mountainous and varied topography. Wind can speed up as it flows down a mountainside or through the gaps between the islands. And moist air produces more rain when it hits the side of a mountain.
“On one side you may see lots of rain; on the other side you may see lots of wind,” Professor Nugent said. “It’s so localized, valley to valley, neighborhood to neighborhood, house to house just in terms of what the impacts may be.”
Tropical Storm Lane’s slow speed means that it is likely to dump large amounts of rain. Lingering hurricanes can cause devastating flooding and billions of dollars of damage, as Texans learned last year when Hurricane Harvey stalled over the state. Photo Credit Jessica Henricks, via Associated Press
Professor Nugent said she had considered fleeing the state, but by the time she looked at ticket prices earlier this week, flights were too expensive. On Friday, airports were open but there were delays and cancellations across the state. American Airlines canceled flights in and out of Kahului. Hawaiian Airlines said that some West Coast to Maui flights were delayed and that some inter-island flights were canceled.
Nearly all of Hawaii’s commodities come through a harbor in Honolulu, which has been closed by the United States Coast Guard, said Maj. Gen. Arthur J. Logan, director of the Hawaii Emergency Management Agency. But he said locals need not worry about running out of food and supplies: Full containers were ready to be moved and ships were on call to be deployed when the harbor reopens.
“I feel very confident we’ll keep the supply chain moving,” General Logan said.
Throughout the day, it was as if different islands of Hawaii were experiencing different storms.
On the Island of Hawaii, torrential rain continued. At one point, Saddle Road, the main east-to-west thoroughfare on the island, was blocked by a landslide. The city of Hilo and other parts of the island’s east side were on their third day of flash-flood alerts, and Rainbow Falls, which is usually a peaceful place, was gushing rivers of brown water. Five tourists from California were rescued from a flooded vacation home in Hilo on Thursday, according to The Associated Press.
It all meant that Randy Bruner’s driveway in Pahoa, on Hawaii Island, looked like a rushing creek. “When it’s pouring down rain, there’s a river running through where I live,” Mr. Bruner said. Photo Employees of a Honolulu hotel filled sandbags in preparation for the storm. Credit John Locher/Associated Press
On Maui, the fires left one woman burned and in need of an air evacuation to Oahu. Officials said more than 900 people were taking shelter in the county, although at one point, a hurricane shelter had to be evacuated because of flames in the area.
Victoria Monroe, a tourist from Orange County, Calif., was sheltering in place at the Marriott’s Maui Ocean Club in Lahaina, with a view of two of the fires.
“It was at the top of the hill and it went all the way down toward the ocean,” Ms. Monroe said of one fire. “I thought it was a volcano erupting.”
Her vacation was alternating between hellish and picturesque. “It’s still really pretty out here,” she said, hours before an alert in her hotel instructed people to go inside because of “dust storms.”
And on the Island of Kauai, residents were still waiting for the winds to pick up, anxious that the storm could lead to a repeat of the flooding that devastated part of the island in April. Those floods breached a major highway in four places, closing it to all but local resident traffic. Tourists were banned.
“We’ve been through so many disasters that you have to love it or leave it,” said Teri Tico, a lawyer who lives on the beach in Haena but left ahead of the storm.
Mike Kuntz, a Haena resident who is staying put, said he had to console his daughter as the storm approached. “I want to get out of here,” he recalled her saying, “but I have nowhere to go.”
NIOSH Investigating Deaths Associated with Fracking Flowback Operations
Oil Well Drilling Fatalities
Though the investigations are not complete, NIOSH has learned about several worker fatalities
associated with flowback operations. According to their information, at
least four workers have died since 2010 from what appears to be acute
chemical exposures during flowback operations at well sites in the
Williston Basin (North Dakota and Montana). The
available information suggests that these cases involved workers who
were gauging flowback or production tanks or involved in transferring
flowback fluids at the well site. Often these fatalities occurred when
the workers were performing their duties alone.
Potential Exposures during Flowback Operations
Before
a well begins producing, each horizontal well needs between 2.4 and 7.8
million gallons of freshwater. This water is pumped from local water
sources like streams and rivers and then mixed with chemicals and
sand. It is then injected into the well bore under high pressure. The
force of this mixture is strong enough to fracture the shale to
stimulate the flow of gas or oil. As the gas or oil begins flowing, the
mixture is pushed back up along with other substances picked up from
deep underground like heavy metals, brine, naturally occurring
radioactivity from uranium and volatile hydrocarbons. Flowback
refers to this process of the fluids from the wellbore which return to
the surface and are collected after hydraulic fracturing is
completed. After separation, flowback fluids are typically stored
temporarily in tanks or surface impoundments (lined pits, ponds) at the
well site. Liquid hydrocarbons from the separation process are routed to
production tanks where they must be stored and then disposed of.
Workers periodically gauge the fluid levels in flowback and production
tanks with hand-held gauges (sticks and tapes) through access hatches
located on the top of the tank. Some problems which need to be
addressed are the potential and occurrence of tears in linings,
spills, and leaks in the waste storage tanks and ponds. In addition to
the onsite problems, local sewage treatment plants and landfills are
often not equipped to test for and handle this amount of waste infused
with salts, metals, and solvents. Hydrogen sulfide (sour gas) is
well recognized as a toxic exposure hazard associated with oil and gas
extraction and production. However, less recognized by many employers
and workers is that many of the chemicals found in volatile hydrocarbons
are acutely toxic at high concentrations. Recently, NIOSH conducted exposure assessments to identify chemical hazards to workers involved in flowback operations. Results
from initial field studies suggest that certain flowback
operations/activities can result in elevated concentrations of volatile
hydrocarbons in the work environment that could be acute exposure
hazards. Volatile hydrocarbons have been found to affect the eyes,
breathing, and the nervous system and at high concentrations may also
affect the heart causing abnormal rhythms. Toxic inhalation and
chemical exposure injuries are serious. Workers Compensation may provide
some remuneration for such injuries, but if it can be proved that your
employer deliberately placed you in harm's way, other legal actions can
be taken to gain additional compensation to provide for your medical and
future needs.
=========================
Gases and vapors continue to pose hazards on oil and gas well sites during gauging, fluid transfer, and disposal
Posted on by Kyla
Retzer, MPH; Emily Schmick, MSPH, CIH; Alejandra Ramirez-Cardenas, MPH;
Bradley King, PhD, MPH, CIH; and John Snawder, PhD, DABT
1)
The worker peers down an open hatch of the oil tank. 2) In some
regions, workers gauge oil tanks by opening tank hatches, visually
observing liquid levels, and then manually measuring liquid oil levels.
3) As commonly designed, fixed oil tanks often are interconnected for
both liquid and vapor, allowing contents to equalize over multiple
tanks. Equalization of tanks can result in a high volume of off-gassed
vapors when a tank hatch is opened. 4) The windsock is a visual
indicator for the worker to stay positioned upwind while gauging. Photo
courtesy of OSHAA previous NIOSH report (2016)1
described the death of nine oil and gas extraction workers that
occurred during gauging or sampling activities at open thief hatches on
crude oil storage tanks. Hydrocarbon gases and vapors (HGVs) and
associated oxygen displacement were the primary or contributory factors
in these fatalities. Additionally, wellsite exposure assessments
conducted by OSHA and NIOSH identified HGVs at open thief hatches in
concentrations that were immediately dangerous to life or health (IDLH)
and in excess of the lower explosive limit (LEL), creating a chance for
fires and explosions. It has been demonstrated that HGVs can build up
under pressure and rapidly escape when thief hatches of production,
flowback, and other tanks are opened, creating a highly flammable and
oxygen-deficient environment, even in areas not considered to be a
confined space. Acute exposure to HGVs can have narcotic effects on
workers (i.e. dizziness, disorientation) as well as affect the eyes,
lungs, and central nervous system. The simultaneous exposure of HGVs
combined with a low oxygen atmosphere may also pose a risk for sudden
cardiac death, especially in individuals with pre-existing coronary
artery disease. In addition to HGVs, hydrogen sulfide (H2S), a widely recognized hazard in the oil and gas extraction industry, continues to persist as a cause of death among workers2.
Hydrogen sulfide is naturally present in some oil and gas deposits and
may be produced as a by-product of the desulfurization process of these
fuels. Workers in all operations during oil and natural gas exploration
and production may be exposed to H2S. This blog provides an update on fatalities, injuries, and exposures associated with hazardous gases and vapors (HGVs and H2S)
in the oil and gas extraction industry, and alerts employers to
exposures that can occur while working around oil and gas process
fluids.
What’s New?
NIOSH has conducted surveillance of worker fatalities and severe
injuries in the oil and gas extraction industry, including those that
may be associated with exposure to or ignition of hazardous gases and
vapors. Fatalities are identified using the NIOSH Fatalities in Oil and
Gas Database (FOG). The federal Occupational Safety and Health Administration (OSHA) severe injury data set
provides a source to identify severe non-fatal incidents among oil and
gas extraction workers. In addition to fatality and injury surveillance,
NIOSH has conducted additional worker exposure assessments at oil and
gas worksites to examine potential hazardous exposures, including oxygen
concentration and hazardous and flammable gas and vapor concentrations
(HGVs and H2S) during various worker activities.
Surveillance
NIOSH researchers sought to determine the number of fatalities and
hospitalizations with known or potential exposure to hazardous gases and
vapors as well as fires and explosions while working around process
fluids, including waste water, flowback, petroleum condensate, or crude
oil. Waste water is also sometimes referred to as produced water, brine,
salt water, etc., but often still contain hydrocarbons. The following definition was developed to identify cases: During
2015-2016, fatalities or hospitalizations related to the ignition,
inhalation, or suspected inhalation of HGVs and/or H2S while
handling process fluids (e.g. fluid transfer) or working on tanks
containing process fluids at oil and gas well sites or waste water
disposal sites. Cases were reviewed and categorized by event type,
activity type, location, and fluid type. During 2015—2016, there were eight oil and gas worker fatalities during eight separate incidents that met the case definition (see cases in FOG Report ).
Event Type: Three workers died of sudden cardiac
death with potential exposures to hazardous gases and vapors, two
workers died due to fire/explosions, two workers died due to hydrogen
sulfide poisoning, and one worker died due to HGV exposures.
Activity Type: Four workers died while transferring
fluids from tanks to trucks, two workers were tank gauging or sampling,
one worker was at an open tank hatch with unknown activity, and one
worker was doing hotwork (grinding) on top of a tank.
Fluid Type: Four workers were working with produced water, three workers were working with crude oil, and one with flowback.
Site Type: Six workers died at well sites and two workers died at waste water disposal sites.
During 2015-2016, there were ten hospitalizations during ten separate incidents that met the case definition (see cases in FOG Report).
Event Type: Five workers were hospitalized due to fire/explosions, three workers hospitalized due to H2S exposure, and two workers hospitalized due to HGV exposures.
Activity Type: Six workers were tank gauging or
sampling, one worker was transferring fluids, one worker was using a
vacuum truck to remove tank bottoms, one worker was draining condensate
from a separator line (i.e. heater treater), and one was transporting
waste water.
Fluid Type: Three workers were working with
produced water, one with flowback, one with tank bottoms (solids and
waste), one with condensate, one with crude oil, and three were unknown.
Site Type: Nine workers were injured/exposed at well sites and one worker was injured at a waste water disposal site.
These incidents illustrate that hazardous gas and vapor exposures
while handling process fluids continue to occur, either through the
inhalation or ignition of hazardous gases and vapors.
Exposure assessments
In July 2017, NIOSH conducted air monitoring while a trucker was
transferring petroleum condensate from a storage tank onto his truck. As
hydrocarbon fluids were transferred, gases and vapors that were
previously in equilibrium within the storage tank released into the
belly of the truck’s tank. To prevent over pressuring of the truck tank
as liquid was transferred, the gases and vapors were vented directly to
the outside of the back of the truck; no vent line was used to direct
the gases and vapors away from the trunk at a distance. Direct reading
instrument data and bulk air samples were collected at and around the
tanker trunk and later analyzed to determine HGV and H2S
concentrations in the air during this activity. Forward-looking Infrared
(FLIR) video was used to visualize and record the plume of hazardous
gases and vapors that surrounds the tanker truck during the fluid
transfer (click for video). While performing this fluid transfer, hazardous gases and vapors were
measured in concentrations over 348,000 parts per million, or 34.8% of
the air volume. The full analysis of this air sample is shown in Table
1. Table 1. Results for select gases and vapors collected during
petroleum condensate transfer near the venting point behind the tanker
truck
Gas/Vapor
Concentration (ppm)
IDLH (ppm)
Severity (Concentration/IDLH)
Methane**
141,000
5,000*
28
Ethane**
62,600
3,000*
21
Propane**
59,100
2,100*
28
Butanes**
50,900
1,600*
31
Pentanes**
25,500
1,500*
17
Benzene†
175
500
0.35
Toluene†
6.8
500
0.01
Ethylbenzene†
Not Detected
800*
0.0
Xylenes†
0.5
900
0.0
Hexane†
6,000
1,100*
5.5
Heptane†
3,510
750
4.7
Octane†
Not Detected
1,000*
0.0
Nonane†
0.8
800*
0.0
Hydrogen Sulfide‡
450
100
4.5
* Immediately Dangerous to Life or Health (IDLH) values are based on the NIOSH Current Intelligence Bulletin 663,
which states “In the event that the derived health-based IDLH value
exceeds 10% of the LEL concentration for a flammable gas or vapor, the
air concentration that is equal to 10% of the LEL will become the
default IDLH value for the chemical.” ** Analysis Method- Gas chromatography-flame ionization detector (GC-FID) † Analysis Method- Gas chromatography-photoionization detector (GC-PID) ‡ Analysis Method- Direct reading instrument with electrochemical sensor
Recommendations for Employers, Workers, and Incident Investigators
Oil and gas worker fatalities and hospitalizations due to ignition or
inhalation of hazardous gases and vapors and associated oxygen
deficiency are preventable. There are a number of resources available
that employers and workers can use to prevent these incidents.
Employers
Implement recommendations contained in the following relevant resources to prevent exposures to hazardous gases and vapors:
National STEPS Network: Multi-Gas Monitors Hazard Alert:
a one-page overview of the importance of the use of multi-gas monitors
on oil and gas well sites. Includes the importance of monitor
calibration, training of workers, heeding of all alarms, and
understanding the limitations of monitors (English and Spanish).
National STEPS Network: Hot Work Hazard Alert:
a one-page overview of how to prevent fatalities associated with hot
work on oilfield tank, tankers and other related equipment (English and
Spanish).
Video: Protecting Oil and Gas Workers from Hydrocarbon Gases and Vapors:
this 13-minute video describes the hazards associated with manual
gauging and fluid sampling on oil and gas production tanks and steps
that employers and workers can take to do this work safely (English and
Spanish).
Workers
Comply with all employer policies and hazard assessments to ensure
you are protected from hazardous gases and vapors. Always wear required
personal protective equipment and your multi-gas monitor and heed all
alarms. Review the videos listed above and each of the National STEPS Network Hazard Alerts to learn more ways to protect yourself.
Incident investigators
Medical examiners and coroners investigating oil and gas worker
fatalities need to be aware of the possibility of hazardous gas and
vapor exposures and request appropriate lab tests. Exposure to high
concentrations of HGVs and oxygen-deficient atmospheres can result in
sudden cardiac death in oil and gas extraction workers. Analysis of
ante-mortem or postmortem blood for documentation of HGV exposure
(2139B) as well as H2S (thiosulfate in blood) is available from clinical toxicology laboratories.
Help Wanted!
NIOSH is working with industry partners to continue to evaluate the
magnitude of hazards and effectiveness of controls in the oil and gas
industry. We are looking for industry partners who are interested in
participating in studies and/or providing access to sites to assess
exposures. If you have questions, or would like to provide pertinent
information on this topic, please contact us via the blog comment box or
by email at kretzer@cdc.gov. Kyla D. Retzer, MPH, is an Epidemiologist in the NIOSH Western States Division. Emily Schmick, MSPH, CIH, is an ORISE Research Fellow in the NIOSH Western States Division. Alejandra Ramirez-Cardenas, MPH, is a Research Assistant in the NIOSH Western States Division. John Snawder, PhD, DABT, is a Research Toxicologist in the NIOSH Division of Applied Research and Toxicology. Bradley King, PhD, MPH, CIH, is an Industrial Hygienist in the NIOSH Western States Division.
Note:The objective of this
blog entry is to describe a potential emerging occupational hazard in
the oil and gas extraction industry. Additionally, it is meant to
request help from stakeholders for more information related to
illnesses, injuries, and fatalities associated with fluid transfer. To
keep the blog discussion focused on worker health, we may choose not to
respond to comments that do not pertain to worker exposures.
Acknowledgements
Ted Teske, Ryan Hill, Robert Harrison (California Department of
Public Health), Michael Hodgson (OSHA), J.D. Danni (OSHA), Mike Marshall
(OSHA), Barbara Alexander
References
Esswein EJ, Retzer K, King B, Cook-Shimanek M. Environmental and
Health Issues in Unconventional Oil and Gas Development. Kaden DA, Rose
TL, eds. Waltham MA: Elsevier, 2016 Jan: 93-105.
Harrison RJ, Retzer K, Kosnett MJ, et al. Sudden Deaths Among Oil and
Gas Extraction Workers Resulting from Oxygen Deficiency and Inhalation
of Hydrocarbon Gases and Vapors — United States, January 2010–March
2015. MMWR Morb Mortal Wkly Rep 2016;65:6–9. DOI: http://dx.doi.org/10.15585/mmwr.mm6501a2 NIOSH [2013]. Current intelligence bulletin 66: derivation of
immediately dangerous to life or health (IDLH) values. Cincinnati, OH:
US Department of Health and Human Services, Centers for Disease Control
and Prevention, National Institute for Occupational Safety and Health,
DHHS (NIOSH) Publication 2014–100. https://www.cdc.gov/niosh/docs/2014-100/pdfs/2014-100.pdf
=========================
Sudden Deaths Among Oil and Gas
Extraction Workers Resulting from Oxygen Deficiency and Inhalation of
Hydrocarbon Gases and Vapors — United States, January 2010–March 2015
Robert J. Harrison, MD1; Kyla Retzer, MPH2; Michael J. Kosnett, MD3,4; Michael Hodgson, MD5; Todd Jordan, MSPH6; Sophia Ridl2; Max Kiefer, MS2 (View author affiliations) View suggested citation
Summary
What is already known on this topic? Oil and gas extraction workers experience high rates of traumatic
work-related fatalities. Tank gauging and sampling activities can expose
workers to high concentrations of hydrocarbon gases and vapors (HGVs),
in some cases at levels immediately dangerous to life or health. What is added by this report? Exposure to high concentrations of HGVs and oxygen-deficient
atmospheres during manual tank gauging and sampling can pose a risk for
sudden cardiac death. Although the first two deaths described in this
series were not immediately recognized as work-related, the occurrence
of seven additional deaths under similar circumstances suggests that HGV
exposure during manual tank gauging and sampling can be
life-threatening. What are the implications for public health practice? Health care professionals need to be aware of the risks to oil and
gas extraction workers related to exposure to high concentrations of
HGVs and to oxygen deficiency. Medical examiners and coroners
investigating worksite fatalities need to be aware that these exposures
can result in sudden cardiac death and include appropriate toxicology
analyses in their investigation. A thorough worksite assessment is
warranted if any workers exhibit signs or symptoms of HGV exposure or
oxygen deficiency. Implementation of measures to reduce or eliminate HGV
exposures is important, including practices that allow for alternative
fluid sample collection points, remote monitoring of fluid levels,
proper use of gas monitors, respiratory protection meeting the
requirements of the Occupational Safety and Health Administration, and
worker training.
In 2013, an occupational medicine physician
from the University of California, San Francisco, contacted CDC’s
National Institute for Occupational Safety and Health (NIOSH), and the
Occupational Safety and Health Administration (OSHA) about two oil and
gas extraction worker deaths in the western United States. The suspected
cause of these deaths was exposure to hydrocarbon gases and vapors
(HGVs) and oxygen (O2)-deficient atmospheres after opening
the hatches of hydrocarbon storage tanks. The physician and experts from
NIOSH and OSHA reviewed available fatality reports from January 2010 to
March 2015, and identified seven additional deaths with similar
characteristics (nine total deaths). Recommendations were made to
industry and regulators regarding the hazards associated with opening
hatches of tanks, and controls to reduce or eliminate the potential for
HGV exposure were proposed. Health care professionals who treat or
evaluate oil and gas workers need to be aware that workers might report
symptoms of exposure to high concentrations of HGVs and possible O2
deficiency; employers and workers need to be aware of this hazard and
know how to limit exposure. Medical examiners investigating the death of
oil and gas workers who open tank hatches should consider the
contribution of O2 deficiency and HGV exposure. Workers at oil and gas well sites often manually gauge the level of
fluid or collect a sample from storage tanks containing process fluids.
These workers climb to the top of the tanks, open a “thief” hatch (a
closable aperture on atmospheric tanks, used to sample the tank
contents) (Figure),
and either place a device into the hatch to measure the fluid level or
lower a “thief” sampler (a hollow tube) into the tank to collect liquid
samples. In 2013, an occupational medicine physician from the University
of California, San Francisco, received a report of a 2012 oil and gas
worker fatality in North Dakota; that state’s medical examiner
attributed death to the inhalation of petroleum hydrocarbons. The male
worker, aged 21 years, was gauging crude oil production tanks on the
well site, at night and alone. A coworker found the victim unconscious
near the open hatch. Colleagues initiated cardiopulmonary resuscitation,
and the worker was transported to the hospital where he was pronounced
dead approximately 2 hours later. An autopsy found no obvious signs of
traumatic injury. Toxicology testing identified detectable quantities of
low–molecular weight hydrocarbons (propane and butane), and evidence of
heavier molecular weight hydrocarbons. No indication of exposure to
hydrogen sulfide (H2S) was identified. Initially, the death
was attributed to cardiovascular disease and later to hydrocarbons. The
occupational medicine physician subsequently identified a second worker
who died from a sudden cardiac event in 2010 while performing tank
gauging; H2S was excluded as a factor. The physician contacted NIOSH and OSHA about these two deaths. To identify other oil and gas extraction worker fatalities associated
with exposure to HGVs, the physician and experts from NIOSH and OSHA
reviewed media reports, OSHA case files, and the NIOSH Fatalities in Oil
and Gas database. Cases were defined as nontraumatic oil and gas
extraction worker deaths occurring during January 2010–March 2015, in
which the workers were 1) performing tank gauging, sampling, or fluid
transfer activities at oil and gas well sites; 2) working in proximity
to a known and concentrated source of HGVs (e.g., an open hatch); 3) not
working in a confined space; and 4) not exposed to H2S,
fires, or explosions. All available information on identified fatalities
was reviewed, including OSHA investigations, coroner and toxicology
reports, gas monitor data, and exposure assessment data. Nine deaths, occurring from January 2010 to March 2105, were identified (Table);
six of the deaths occurred during 2014. Three deaths occurred in
Colorado, three in North Dakota, and one each in Montana, Oklahoma, and
Texas. The median age of workers was 51 years (range = 20–63 years), and
all were male. All of the victims were working alone at the time of the
incidents and were found collapsed on a tank or catwalk, or at the base
of the catwalk stairs. In at least five cases, the hatch was open when
the worker was found. Five of the fatalities occurred during the
collection of a fluid sample, and four occurred during tank gauging.
Toxicologic data on HGVs were not consistently collected during autopsy,
but petroleum hydrocarbon vapors were noted as a cause of death for
three workers. Only one of the nine workers was known to have been provided a
respirator, but fit-testing had not occurred, and the air-purifying
respirator was not suitable for high concentrations of HGVs or O2 deficiency. The exposure assessment conducted by OSHA following the 2010 case found O2 concentrations as low as 11% at 1 foot above the open thief hatch (O2
concentrations in ambient air = 21%). In addition, HGV concentrations
were in excess of the lower-explosive limit (minimum concentration of a
gas necessary to support its combustion in air), suggesting exposures
high enough (>10,000 parts per million [ppm]) to cause acute central
nervous system symptoms. In case number seven, the worker wore a
data-logging, continuous multi gas monitor as a regular work practice.
Three weeks before the fatal event, he was examined in an emergency
department after experiencing altered consciousness while gauging a
tank. Gas monitor data during this event revealed a 5-minute interval,
concurrent with his symptoms, when O2 concentrations were in
the range of 10% to 15% and flammable HGVs exceeded the lower-explosive
limit. On the day of his death, the gas monitor again indicated that the
lower-explosive limit had been exceeded, with O2 concentrations as low as 7%.
During January 2010–March 2015, at least nine deaths of oil and gas
workers occurred in the United States, with exposure to HGVs a confirmed
or suspected factor. Oil and gas extraction is a high-risk industry,
with overall occupational fatality rates seven times the national
average (1). Although safety hazards in the industry are
well-known, few published reports address chemical exposures and acute
occupational illness associated with oil and gas extraction. Recent
exposure assessments have identified that opening thief hatches and
manual gauging or sampling from hydrocarbon-containing tanks, outdoors
in nonconfined spaces, is widely practiced and poses substantial and
potentially lethal hazards to workers (2–4). These hazards
include sudden exposure to high concentrations (>100,000 ppm) of
low–molecular weight HGVs, accompanied by displacement of air, resulting
in O2 deficiency. Inhaled O2 concentrations of
<15% can significantly impair central nervous system function, and
concentrations of <10% can result in loss of consciousness and
possible death within seconds to minutes (5). Low O2
blood levels (hypoxemia) can exacerbate cardiac ischemia and increase
the release of epinephrine (adrenalin). High concentrations (i.e.,
50,000 ppm to ≥100,000 ppm) of low–molecular weight hydrocarbons,
particularly butane, have been shown in animal studies and human reports
to sensitize the heart to epinephrine-induced ventricular fibrillation,
a lethal cardiac arrhythmia (6–8). The simultaneous exposure to high levels of low–molecular weight HGVs and a low O2
atmosphere above an open tank hatch poses a risk for sudden cardiac
death. Preexisting coronary artery disease can exacerbate that risk. In
addition, high levels of low–molecular weight HGVs can exert anesthetic
effects that contribute to central nervous system depression (9).
The exposure-assessment samples also showed concentrations of propane,
butane, pentane, and 2-methylbutane exceeding 100% of the
lower-explosive limit (3). Concentrations of explosive gases in
excess of 10% of the lower-explosive limit are considered immediately
dangerous to life or health. Because of the nine identified fatalities,
the exposure-assessment findings, and the potential mechanism for sudden
cardiac death, OSHA, NIOSH and multiple industry stakeholders
collaboratively issued a hazard alert on tank gauging at oil and gas
well sites (10). In addition, the Bureau of Land Management has
proposed changes to current federal regulations* that replace outdated
technology and practices with remote tank gauging technologies, reducing
or eliminating the need for manual tank gauging. Health professionals need to recognize the signs and symptoms of exposure to high concentrations of HGVs and possible O2-deficient
atmospheres in oil and gas workers. Health and safety professionals
need to recognize and act on nonfatal warning signs and symptoms, such
as dizziness, confusion, immobility, and collapse in oil and gas workers
who might have been exposed to high concentrations of HGVs and to O2-deficient
atmospheres. As required by OSHA regulations, employers should reduce
or eliminate the hazard; this can include practices that allow for
alternative fluid sample collection points, remote monitoring of fluid
levels, proper use of gas monitors, respiratory protection meeting OSHA
requirements, and worker training. Employers also need to ensure that
workers do not work alone where they might have risks for exposures to
high concentrations of hydrocarbons and low-O2 environments.
Having automated external defibrillators available at worksites is also
important. Medical examiners and coroners investigating workplace
fatalities need to be aware of the possibility that exposure to high
concentrations of HGVs and O2-deficient atmospheres can
result in sudden cardiac death in oil and gas extraction workers.
Analysis of antemortem or postmortem blood for documentation of HGV
exposure is available from clinical toxicology laboratories.
1Division of Occupational and Environmental Medicine, University of California, San Francisco; 2National Institute for Occupational Safety and Health, Western States Division, CDC; 3Division of Clinical Pharmacology and Toxicology, University of Colorado School of Medicine; 4Department of Environmental and Occupational Health, Colorado School of Public Health; 5Office of Occupational Medicine and Nursing, Occupational Safety and Health Administration, Washington, DC; 6Health Response Team, Occupational Safety and Health Administration, Salt Lake City, Utah.
Mason KL, Retzer KD, Hill R, Lincoln JM. Occupational fatalities
during the oil and gas boom—United States, 2003–2013. MMWR Morb Mortal
Wkly Rep 2015;64:551–4. PubMed
Esswein EJ, Snawder J, King B, Breitenstein M, Alexander-Scott M,
Kiefer M. Evaluation of some potential chemical exposure risks during
flowback operations in unconventional oil and gas extraction:
preliminary results. J Occup Environ Hyg 2014;11:D174–84. CrossRefPubMed
King B, Esswein E, Retzer K, et al. UPDATE: reports of worker
fatalities during manual tank gauging and sampling in the oil and gas
extraction industry. In: NIOSH Science Blog. Washington DC: National
Institute for Occupational Safety and Health. http://blogs.cdc.gov/niosh-science-blog/2015/04/10/flowback-3/.
Miller TM, Mazur PO. Oxygen deficiency hazards associated with
liquefied gas systems: derivation of a program of controls. Am Ind Hyg
Assoc J 1984;45:293–8. CrossRefPubMed
Chenoweth MB. Ventricular fibrillation induced by hydrocarbons and epinephrine. J Ind Hyg Toxicol 1946;28:151–8. PubMed
Reinhardt CF, Azar A, Maxfield ME, Smith PE Jr, Mullin LS. Cardiac
arrhythmias and aerosol “sniffing”. Arch Environ Health 1971;22:265–79. CrossRefPubMed
Fuke C, Miyazaki T, Arao T, et al. A fatal case considered to be due
to cardiac arrhythmia associated with butane inhalation. Leg Med
(Tokyo) 2002;4:134–8. CrossRefPubMed
Drummond I. Light hydrocarbon gases: a narcotic, asphyxiant, or flammable hazard? Appl Occup Environ Hyg 1993;8:120–5. CrossRef
FIGURE. An oil field worker manually gauges the level of process fluid in a fixed production oil tank* — United States
Photo/Todd Jordan, Occupational Safety and Health Administration *1) The worker peers down an open hatch of the oil tank. 2) In some
regions, workers gauge oil tanks by opening tank hatches, visually
observing liquid levels, and then manually measuring liquid oil levels.
3) As commonly designed, fixed oil tanks often are interconnected for
both liquid and vapor, allowing contents to equalize over multiple
tanks. Equalization of tanks can result in a high volume of off-gassed
vapors when a tank hatch is opened. 4) The windsock is a visual
indicator for the worker to stay positioned upwind while gauging.
TABLE. Sudden
deaths caused by inhalation of hydrocarbon gases and vapors and oxygen
deficiency among oil and gas extraction workers — United States, January
2010–March 2015
Worker
Year of death
Age (yrs)
State
Job title
Job task
Location/position of decedent when found
Time of day found
Coroner’s stated cause of death
1
2010
30
Montana
Crew worker
Gauging
Slumped over on catwalk
3:00 a.m.
Hypertensive and atherosclerotic cardiovascular disease
2
2012
21
North Dakota
Flow tester
Gauging
On catwalk next to open hatch
12:30 a.m.
Hydrocarbon poisoning due to inhalation of petroleum vapors
3
2013
39
North Dakota
Truck driver
Collecting sample
On knees, slumped over catwalk railing in front of open hatch
Suggested citation for this article:
Harrison RJ, Retzer K, Kosnett MJ, et al. Sudden Deaths Among Oil and
Gas Extraction Workers Resulting from Oxygen Deficiency and Inhalation
of Hydrocarbon Gases and Vapors — United States, January 2010–March
2015. MMWR Morb Mortal Wkly Rep 2016;65:6–9. DOI: http://dx.doi.org/10.15585/mmwr.mm6501a2.
Use of trade names and commercial sources is for identification only and does not imply endorsement by the U.S. Department of
Health and Human Services. References to non-CDC sites on the Internet are
provided as a service to MMWR readers and do not constitute or imply
endorsement of these organizations or their programs by CDC or the U.S.
Department of Health and Human Services. CDC is not responsible for the content
of pages found at these sites. URL addresses listed in MMWR were current as of
the date of publication. All HTML versions of MMWR articles are generated from final proofs through an automated process.
This conversion might result in character translation or format errors in the HTML version.
Users are referred to the electronic PDF version (https://www.cdc.gov/mmwr)
and/or the original MMWR paper copy for printable versions of official text, figures, and tables
