CSB Releases
Safety Bulletin Emphasizing Dangers of Working on Piping and Equipment
That May Contain Flammable or Chemically Reactive Material
Washington, DC, July 15, 2004 – The U.S. Chemical Safety and Hazard
Investigation Board (CSB) today released a Safety Bulletin calling on
chemical plant and refinery operators to exercise appropriate caution when
performing work on piping and equipment that could contain hazardous
materials.
The bulletin, set to be considered by the Board at a public meeting today,
results from the CSB’s investigation into a January 13, 2004, explosion
and fire at the Huntsman Petrochemical facility in Port Neches, Texas,
where two employees were seriously burned and significant damage occurred
to nearby equipment. The explosion and fire occurred as workers attempted
to purge a thousand-foot-long chemical process pipe in preparation for a
cutting and welding operation.
Huntsman managers and workers were aware of the importance of completely
removing hazardous material before cutting into the piping, and relevant
warnings were contained in the company’s written operating procedures. In
this incident, workers first purged the piping with nitrogen to force out
residual chemicals, including a hazardous mixture of peroxide and alcohol
that reacts violently when heated. But unknown to the workers, the piping
included a 300-foot-long section that was three feet lower than the rest
of the piping, and despite the nitrogen purge, a significant amount of the
hazardous mixture remained trapped.
The next step in the operation was to use high-temperature steam to purge
the piping of what workers believed would be a small amount of residual
flammable hydrocarbon vapor. But the steam heated the peroxide that was
trapped in the low section of piping. The peroxide then began to
decompose, releasing heat and creating intense pressure. The pressure blew
out a valve gasket and violently ruptured the pipe. Flammable vapors shot
out of the openings and ignited into a large fireball, injuring plant
workers.
After the accident, Huntsman found two drains in the low section of the
pipe, which could have been used to remove the trapped liquid. Had
Huntsman’s procedures called for reviewing plant pipe drawings and
physically walking the entire line within the work boundaries, the
accident would likely have been avoided, CSB said.
CSB’s Safety Bulletin points out that chemical plant and refinery
operators routinely open piping to perform maintenance, change components,
or reroute lines. The Bulletin states, “Safe work practices dictate the
removal or mechanical isolation of hazardous material from piping and
equipment … before commencing work.”
Under “Lessons Learned,” the Bulletin notes that work involving the
opening of chemical process pipes should never be considered routine. The
Bulletin recommends that facilities should:
- Physically examine all piping and components
between isolation devices such as valves, and be sure piping drawings are
current
- Use the drawings to identify key components, such as
low-point drains that can be used to remove dangerous chemicals
- Prepare a specific written procedure for removing
hazardous material and consider the consequences of working on piping that
is not completely purged.
CSB investigators conducted a three-day investigation of the January
incident. Huntsman personnel also investigated the event and identified a
number of corrective actions.
CSB is an independent federal agency charged with investigating industrial
chemical accidents. The agency’s board members are appointed by the
president and confirmed by the Senate. CSB investigations look into all
aspects of chemical accidents, including physical causes such as equipment
failure as well as inadequacies in safety management systems. The
Board does not issue citations or fines but does make safety
recommendations to plants, industry organizations, labor groups, and
regulatory agencies such as OSHA and EPA. Further information about CSB is
available from www.csb.gov. For more information, contact Sandy Gilmour
(Public Affairs Contractor), 202-261-7614 or 202-251-5496 (cell), or
Daniel Horowitz, 202-261-7613.
CSB Releases Safety Bulletin
Warning of Dangers of Sodium Hydrosulfide (NaHS) in the Workplace;
Outlines Safe Practices to Prevent Harm
Washington, DC, July 15, 2004 – The U.S. Chemical Safety and Hazard
Investigation Board (CSB) today released a Safety Bulletin that warns of
the dangers of sodium hydrosulfide and recommends safe practices to
prevent accidents when handling the chemical.
CSB investigators uncovered 45 accidents associated with sodium
hydrosulfide that have caused 32 deaths and 176 injuries since 1971. They
noted, however, that accident data are incomplete and there may have been
additional deaths and injuries attributable to the chemical. The Safety
Bulletin is an outgrowth of the Board’s investigation of a January 2002
accident involving sodium hydrosulfide that caused two deaths and eight
injuries at an Alabama paper mill.
Sodium hydrosulfide, known by its chemical symbol NaHS (often pronounced “nash”)
is used in the leather tanning, pulp and paper, chemical, dye, and mineral
extraction industries. NaHS is used as a pure solid (flake) or more
commonly as a solution in water.
The Safety Bulletin points out that when NaHS is inadvertently combined
with acid materials, deadly hydrogen sulfide gas is produced. Such
inadvertent mixing can occur in a chemical process sewer, for example.
Hydrogen sulfide gas has the characteristic smell of rotten eggs. The
bulletin notes that hydrogen sulfide is insidious, because even moderate
exposures impair a human’s ability to smell the gas by deadening the
nerves in the nose. Health effects from inhalation range from shortness of
breath and severe lung damage at lower concentrations (50-150 parts per
million in air) to rapid unconsciousness and death at higher levels
(800-1,000 parts per million).
The Bulletin describes several common themes in NaHS incidents: spills,
leaks, or inadvertent mixing that bring NaHS solutions into contact with
acid; engineering controls that are inadequate, including lack of
detection devices or ventilation systems; and inappropriate emergency
response, where workers and responders may rush to help a fallen worker
before sampling the air or donning protective gear.
The CSB Bulletin noted that companies handling NaHS must provide workers
with material safety data sheets to apprise them of the chemical’s
potential danger. However, the CSB found that the hazard information in
MSDSs varies significantly among NaHS manufacturers. The CSB recommended
that companies that use NaHS review safety information from several
sources, including the CSB Safety Bulletin, to gain a full understanding
of the hazards.
The Bulletin urges companies to reduce NaHS hazards through engineering
and design improvements and lists specific ways that companies can improve
NaSH safety, such as air monitoring, safe storage, and proper use of
protective gear. The Safety Bulletin was to be considered for final
approval by the full Board at a public meeting in Washington today.
CSB is an independent federal agency charged with investigating industrial
chemical accidents. The agency’s board members are appointed by the
president and confirmed by the Senate. CSB investigations look into all
aspects of chemical accidents, including physical causes such as equipment
failure as well as inadequacies in safety management systems. The Board
does not issue citations or fines but does make safety recommendations to
plants, industry organizations, labor groups, and regulatory agencies such
as OSHA and EPA. Further information about CSB is available from
www.csb.gov. For more information, contact Sandy Gilmour (Public Affairs
Contractor), 202-261-7614 or 202-251-5496 (cell), or Daniel Horowitz, CSB
202-261-7613.
CSB Presents Plan for Expanded
Recommendations Implementation Program
Washington, DC, July 15, 2004 — Senior staff from the U.S. Chemical Safety
and Hazard Investigation Board (CSB) presented their plans for an expanded
Recommendations Program to Board Members in a public meeting in Washington
this morning. The Recommendations Program is charged with achieving the
implementation of the recommendations that arise from completed chemical
accident investigations. The program will also play an important role in
the increased outreach activities of the CSB.
Dr. Manuel Gomez, who joined the CSB as Director of Recommendations
earlier this summer, and Jordan Barab, Senior Recommendations Specialist,
presented the Recommendations Program update. They outlined plans for a
more comprehensive program through vigorous pursuit of open
recommendations, improved dissemination of information, implementation of
a new tracking system for recommendations, and a broader CSB outreach
program.
CSB Chairman Carolyn Merritt said, “Following investigations into the root
and contributing causes of industrial chemical accidents, the CSB issues
recommendations to companies, state and federal agencies, industry
associations, and others. The CSB hopes that other similar accidents can
be prevented through the implementation of these recommendations.
Successfully implementing these recommendations is a critical part of the
Board’s mission.”
At today’s meeting, the CSB noted that the Environmental Protection Agency
has recently acted on a major recommendation from the Board’s 2002
reactive hazard investigation. The EPA now requires reporting of reactive
chemical incidents under its Risk Management Program, which will allow
better tracking and evaluation of incidents at thousands of facilities
around the nation. The Board voted to close this recommendation based on
“acceptable action.”
“EPA’s recent rulemaking action on reporting is an example of the progress
our recommendations are making across the country. We are excited to
pursue broader implementation of safety recommendations, which is vital to
the mission of the agency. With a strong outreach plan, the information
gained from our accident investigations will be used even more broadly to
prevent accidents,” Dr. Gomez said. Dr. Gomez said the team would work
with stakeholders to ensure that the appropriate organizations are made
aware of the CSB’s efforts to improve safety whenever chemicals are used
in industry.
Dr. Gomez brings over 25 years of multi-disciplinary experience in
occupational and environmental health and safety to the CSB. He has
previously worked as a consultant, director of the scientific affairs
division of a non-profit organization, professor, researcher, and
compliance officer. He is a Certified Industrial Hygienist, a member of
numerous professional societies, and the author of a book and several
scientific papers and presentations.
The CSB is an independent federal agency charged with investigating
industrial chemical accidents. CSB investigations look into all aspects of
chemical accidents, including physical causes such as equipment failure as
well as inadequacies in safety management systems. Typically, the
investigations involve extensive witness interviews, examination of
physical evidence, and chemical and forensic testing.
The Board does not issue citations or fines but does make safety
recommendations to plants, industry organizations, labor groups, and
regulatory agencies such as OSHA and EPA. Further information about the
CSB is available from www.csb.gov. For more information, contact Kara
Wenzel at 202-261-7642.
