The Risk Management Tool Box Blog

The CSB (Chemical Safety Board)  recently released its investigation report into three accidents that occurred over a 33-hour period in January  2010 at the DuPont Corporation‘s Belle, West Virginia, chemical facility.

The final incident involved a deadly release of the World-War One era chemical weapon - phosgene gas.

The incident is noteworthy because it contains lessons for any individual or organization with process hazards that could result in Major Accident Events (MAEs).  So please read on...

When releasing the report, CSB Chairperson Rafael Moure-Eraso said, "our final report shows in detail how a series of preventable safety shortcomings - including failure to maintain the mechanical integrity of a critical phosgene hose - led to the accidents. That this happened at a company with DuPont‘s reputation for safety should indicate the need for every chemical plant to redouble their efforts to analyze potential hazards and take steps to prevent tragedy".

The accidents began when an alarm sounded leading operators to discover that 2,000 pounds of methyl chloride, a toxic and extremely flammable gas, had been escaping to air for five days.

The next day, workers discovered a separate leak in a pipe carrying oleum, producing a toxic cloud of sulfur trioxide.

The phosgene gas release occurred later the same day, and the exposed worker died the next evening.

Dr. Moure-Eraso said, "DuPont has had a stated focus on accident prevention since its early days. DuPont became recognized across industry as a safety innovator and leader. We at the CSB were therefore quite surprised and alarmed to learn that the DuPont Belle plant had not just one, but three accidents that occurred over a 33-hour period in January 2010".

The CSB investigation found deficiencies in the DuPont Belle facility HSE-MS common across all three accidents. 

DuPont's deficiencies are worth noting because they may apply to virtually any Major Hazard Facility, and were said by the CSB to include:

1.  Maintenance and inspections;

2.  Alarm recognition and management;

3.  Accident investigation;

4.  Emergency response and communications; and

5.  Hazard recognition.

CSB board member and former chairman John Bresland noted the CSB finding that the phosgene hose that burst was supposed to be changed out at least once a month. But the hose that failed had been in service for seven months. Furthermore, the CSB found the type of hose involved in the accident was susceptible to corrosion from phosgene.

Team Lead Johnnie Banks said, "Documents obtained during the CSB investigation showed that as far back as 1987, DuPont officials realized the hazards of using braided stainless steel hoses lined with Teflon,
or polytetrafluoroethylene".

A DuPont internal expert had even recommended the use of hoses lined with Monel, a metal alloy used in corrosive applications. The DuPont official stated: "Admittedly, the Monel hose will cost more than its stainless counterpart. However, with proper construction and design so that stresses are minimized…useful life should be much greater than 3 months. Costs will be less in the long run and safety will also be improved."  Unfortunately for the dead worker, the Monel hose was never used.

Other DuPont documents also showed that  DuPont officials had considered increasing the safety of the area of the plant where phosgene was handled by enclosing the area and venting the enclosure through a scrubber system to destroy any toxic phosgene gas before it entered the atmosphere.

However, the documents indicate the company was concerned with containing costs and decided not to make the safety improvements.

CSB investigators concluded that an enclosure, scrubber system, and routine requirement for protective breathing equipment before personnel entered the enclosure would have prevented any personnel exposures or injuries.

The CSB recommended that OSHA revise the General Industry Standard for Compressed Gases to be at least as effective as the relevant National Fire Protection Association (NFPA) Code 55 (the Compressed Gases and Cryogenics Fluids Code).

This would require secondary enclosures for highly toxic gases such as phosgene and provide for ventilation and treatment systems, interlocked failsafe shutdown valves, gas detection and alarm systems, piping system components, and similar layers of protection.

The US BLS produces information on the Census of Fatal Occupational Injuries.  This important data is available by clicking here.

The first significant update to the United States shipyard standards (Subpart F of 29 CFR 1915) since they were introduced in 1972 occurs today.

The new rules revise requirements for housekeeping, illumination, confined space entry, health and sanitation, lockout-tagout and create a new provision for motor vehicle safety.

According to OSHA statistics, almost 20 per cent of shipyard deaths are due to transportation incidents.

In addition, OSHA has also released a new guidance document which outlines injury prevention measures for rigging operations within the shipyard sector. 

The new guidance document can be found here.

Today I'm posting some of the range of United States websites that may be useful to Safety Advisors working in the USA.  Just click on any of the listed organizations to be taken to their website.

American Society of Safety Engineers.

Chemical Safety Board.

Consumer Product Safety Commission.

Drug Enforcement Administration.

Department of Health and Human Services.

Federal Highway Administration.

Institute of Medicine.

Mine Safety and Health Administration.

National Hearing Conservation Association.

National Institute for Occupational Safety and Health.

Occupational Safety and Health Administration.

 

Whenever it is impractical to reduce a hazards potential to cause harm to the ALARP level using elimination, substitution, engineering or administrative control measures, employers must ensure that appropriate PPE is provided and used by the workforce.

The United States OSHA requirements for PPE are established in the Code of Federal Regulations (CFR).

In the USA, the following American National Standards Institute (ANSI) PPE standards apply to all oil-field work:

• ANSI Z89.1 or ANSI Z89.2 for industrial head protection and head protection of electrical workers respectively;
• ANSI Z87.1 for eye and face protection;
• ANSI Z41.1 for safety footwear;
• ANSI Z88.2-1992 for respiratory protection;
• ANSI Z359.1 for personal fall arrest systems (PFAS);
• ANSI Z358.1 for emergency eyewash and shower equipment;
• ANSI Z117.1-1995 - for safety requirements in confined spaces;
• There is no ANSI standard established for hand protection (gloves); and
• Fire Retardant Clothing (FRC) must meet the performance requirements set out in NFPA 70E (2009) in occupations covered by the OSHA fine rule 1910.269.

OSHA's information booklet on PPE requirements in the USA is available by clicking here.

Fatalities resulting from falls from height are the number one cause of workplace deaths on United States residential construction sites.

In response, OSHA today released its fall protection standard for use in residential construction.

Until today, residential construction employers were allowed to use alternatives to conventional fall protection safeguards without a written site-specific safety plan.

OSHA has now issued a compliance directive stating that employers involved with residential construction must provide workers with fall protection in line with the Standard (1926.501).

Compliance documents are available by clicking here.

A Risk Tool Box JSA on working at height is available by clicking here.

More than 30 workers died from heat stroke whilst working in the United States in the summer months of 2010.

In response, OSHA today launched its summer outreach campaign to educate employers and employees about the dangers associated with working in high ambient temperatures.

The campaign focuses attention on the importance of appropriately scheduling work, providing shade, enforcing rest breaks and providing water which are the cornerstones of heat illness prevention.

High ambient temperatures are a concern for many industries but especially in mining and resources, forestry, farming, road repairs and civil construction.

Further information on the campaign can be found here.

The United States Occupational Safety and Health Administration (OSHA) defines, in its general industry rule, a confined space as having three attributes:

1. Large enough to enter and perform work;
2.  Limited access and egress; and
3. Not designed for continuous occupancy.

Australian Standard (AS2865-2001) defines a confined space as:

“An enclosed or partially enclosed space that is at atmospheric pressure during occupancy and is not intended or designed primarily as a place of work; and

a)                 Is liable at any time to:

i. Have an atmosphere which contains potentially harmful levels of contaminant;

ii. Have an oxygen deficiency or excess; or

iii. Cause engulfment; and

b)           Could have restricted means for entry and exit.

The United Kingdom Health and Safety Executive (UK HSE) says:

“It can be any space of an enclosed nature where there is a risk of death or serious injury from hazardous substances or dangerous conditions (e.g., lack of oxygen)”.

Obvious confined spaces include:

»           Tanks;

»           Stacks;

»           Tunnels; and

»           Trenches.

Some less obvious confined spaces include:

»           Rooms which are inadequately ventilated;

»           Shrouded columns or vessels which render them ‘air tight’;

»           The roof of floating roof tanks; and

»           Rooms and areas that become confined spaces by virtue of the activities being undertaken.

In all cases, confined spaces are particularly dangerous because they may frequently:

»           Contain or have the potential to contain an hazardous atmosphere;

»           Contain a material that has the potential for engulfing the work party;

»           Have an internal configuration that might cause an entrant to be trapped; or

»           Contain other recognized serious safety or health hazards.

Because confined space work can be so dangerous, there are a number of safety-critical controls that need to be applied to all confined space entry activities.  The safety-critical controls are highlighted below:

1. Identify the hazards using the Think 6, Look 6 process;

1. Once hazards are identified, search for ways of eliminating or isolating them;

1.  In addition, always consider eliminating the confined space entry activity;

1. If there are no alternatives to confined space entry, always test for presence of gas;

1. Remember to continuously gas monitor atmospheric conditions;

1. Always ensure that confined space entry  is controlled by an authorized “Permit to Work”;

1. Ensure workers performing confined space entry work are suitable trained;

1. Ensure that a stand-by person acts as a sentry;

1. Provide adequate Supervision, especially where contractors are involved; and

1. Prevent unauthorized entry.

For a useful toolbox presentation on the management of confined space entry work, click the link to our “process safety tools”.