Back to Basics is a weekly feature that highlights important but possibly overlooked information that any EHS professional should know. This week, we examine managing permit-required confined spaces.
Are there spaces in your facility or at your worksites where you need to limit access? Are there spaces that contain a hazardous or potentially hazardous atmosphere, material that could engulf those who enter, or physical hazards like exposed live wires or unguarded equipment or machinery? Are there spaces where walls converge inward or floors that slope downward, tapering into smaller areas where someone could become trapped and asphyxiated?
Confined spaces are ones that are not designed to be continuously occupied and can be difficult to exit during an emergency. Confined spaces include underground vaults, tanks, storage bins, manholes, pits, silos, underground utility vaults, pipelines, and commercial grease traps. Workers who enter confined spaces can face life-threatening hazards that include asphyxiation, drowning or engulfment, electrocution, explosions, fall hazards, and flammable or toxic substances. The atmospheric hazards of confined spaces can be debilitating and even fatal.
For example, on February 2, 2007, at the Orleans Hotel and Casino in Las Vegas, Nevada, plumbers and engineers attempting to address a problem with a grease interceptor/trap in the hotel’s sewer system were overcome by hydrogen sulfide (H2S) inhalation. Two workers were pronounced dead on the scene, and another suffered permanent neurological damage.
Workers in confined spaces can be exposed to air contaminants, one of the American Industrial Hygiene Association’s (AIHA) “Focus Four” construction industry health hazards, along with excessive noise, high temperatures, and manual materials handling.
The Occupational Safety and Health Administration (OSHA) has general industry (29 CFR §1910.146), maritime (Part 1915, Subpart B), and construction industry standards (Part 1926, Subpart AA) regarding confined spaces. The standards contain requirements for entry permit programs, warning signs, training, atmospheric testing and ventilation, attendants, entry supervisors, and rescue and emergency services.
Besides manholes, pipelines, and storage bins, confined spaces include commercial grease traps and railcar and trailer tanks. As food waste decays in commercial grease traps, H2S is released.
Incidents, enforcement
At Austin-Bergstrom International Airport, a worker suffered asphyxiation and died after entering a vault where grease traps were located, and a Texas employer was cited with 2 willful and 3 serious violations, facing $301,188 in OSHA fines. The agency determined the company failed to take steps to prevent employees from entering permit-required confined spaces and failed to provide training to ensure employees understood the hazards of entering a permit-required confined space.
Earlier this year, OSHA announced $1 million in proposed penalties for 4 employers at a poultry processing facility where 6 workers died from nitrogen exposure caused by a malfunctioning freezer. The citations included violations of the confined space standard. Three maintenance employees, who were never trained on the deadly effects of nitrogen exposure, entered a freezer room without taking necessary precautions. OSHA also cited the employers for exit access and lockout/tagout violations.
Servicing trailer and railcar tanks also involve confined space hazards. OSHA cited a Dallas-based railcar servicing company with 11 serious and 2 willful violations, with penalties totaling $419,347, after 2 workers at a Hugo, Oklahoma, facility were sent into a natural gasoline tank car and died from inhaling toxic fumes.
The agency has repeatedly cited another tank railcar cleaning and repair provider and placed the company in its Severe Violators Enforcement Program (SVEP) following a fatality at its Pittston, Pennsylvania, facility and 19 separate instances of employees entering tank cars for cleaning and maintenance without an auxiliary air supply at the company’s Wilmington, Delaware, facility.
This past summer, two OSHA regional offices—Region 5 (Illinois, Indiana, Michigan, Minnesota, Ohio, and Wisconsin) and Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas)—initiated Regional Emphasis Programs (REPs) for permit-required confined space entry inspection and enforcement in the transportation and tank-cleaning industries. OSHA officials are concerned about employers allowing workers to enter railcar or trailer tanks without testing atmospheric conditions, completing confined space entry permits, or providing adequate respiratory protection.
For example, an Ohio worker assigned to clean a chemical tanker trailer collapsed upon entering the tank. A driver answering the employee’s call for help also entered the tank. Both succumbed to fatal toxic fumes. An Illinois worker opened the lid of a tanker trailer containing toluene and was found unresponsive a short time later, lying across the open dome. He was rushed to a nearby hospital and survived after being treated for respiratory failure and cardiac arrest.
Area offices in the regions are checking for compliance with the permit-required confined spaces standard, as well as compliance with the hazard communication, personal protective equipment (PPE), and respiratory protection standards. Common hazards in the industry include chemical, electrical, fall, noise, struck-by, and thermal hazards.
OSHA also prioritizes permit-required confined space inspections across the agency’s area offices in its OSHA Weighting System (OWS). While not as heavily weighted as inspections for process safety management or the “Focus Four” safety hazards—caught-in or -between, electrocution, falls, and struck-by hazards—confined space inspections are assigned two enforcement units (EUs), which is the same number assigned to inspections for amputation hazards, combustible dust, and ergonomics hazards.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) has investigated three major confined space incidents: the October 2007 Xcel Energy Company hydroelectric tunnel fire in Georgetown, Colorado; the November 2006 Valero Refinery asphyxiation incident in Delaware City, Delaware; and the February 1999 Union Carbide Corp. nitrogen asphyxiation incident in Hahnville, Louisiana.
Five people were killed and three others injured when a fire erupted 1,000 feet underground in a tunnel at Xcel’s hydroelectric power plant in Georgetown, located approximately 45 miles west of Denver. Fatally injured workers were trapped deep underground during an operation to apply a coat of epoxy using highly flammable solvents inside of a tunnel that connected two reservoirs with electricity-generating turbines. CSB determined that Xcel and its contractor failed to properly handle flammable substance hazards inside a confined space.
Two contractor employees at Valero’s Delaware City refinery who were preparing to reassemble a pipe on a pressure vessel while it was being purged with nitrogen died of asphyxiation. The first worker, attempting to retrieve a roll of tape from inside the vessel, was overcome by nitrogen, collapsed in the vessel, and died. His coworker, the crew foreman, was asphyxiated while attempting to rescue him.
One worker was killed and another seriously injured at Union Carbide Corporation’s Taft/Star Manufacturing Plant in Hahnville when they were asphyxiated by nitrogen. The incident occurred inside a temporary enclosure the workers had erected over the end of a large open gas pipe to perform a black light inspection. The workers were unaware that the pipe was being purged with nitrogen, creating an oxygen-deficient atmosphere. CSB later issued a safety bulletin on nitrogen asphyxiation hazards.
CSB’s employer recommendations in the Xcel, Union Carbide, and Valero incidents included:
- Post signs containing the warning “Danger, Confined Space: Do Not Enter Without Authorization” at entryways when tanks, vessels, pipes, or other chemical equipment is opened and when nitrogen is added to a confined space, and post an additional sign that warns personnel of the potential nitrogen hazard.
- Ensure that proposal and contracting policies include criteria and procedures for prequalifying or disqualifying contractors based on specific safety performance measures and qualifications.
- Revise contracting policies to require comprehensive review and evaluation of contractor safety policies and procedures such as the permit-required confined space program.
Confined space compliance
You first need to identify confined spaces in your facility or at your worksites, and after identifying them, develop a confined space entry permit and training program. You need to ensure that personnel who are not properly trained, equipped, and permitted do not enter any permit-required confined space.
You need to identify any physical hazards before allowing employees to enter a confined space, and you need to test and monitor for oxygen content, explosive hazards, flammability, and toxicity before and during employee entry.
You must provide and maintain PPE and any other equipment necessary for safe entry, like air-monitoring, communications, or fall protection equipment, and ensure that all confined space entrants use the provided fall protection, PPE, rescue, air-monitoring, ventilation, lighting, and communication equipment.
A trained attendant must always maintain contact with confined space entrants either visually, via phone, or by two-way radio. The monitoring system enables the attendant and entry supervisor to order confined space entrants to evacuate or alert appropriately trained rescue personnel to rescue entrants if necessary.
The permit-required confined spaces standard also contains a requirement for employee cardiopulmonary resuscitation (CPR) training.
A written entry permit must include:
- Name of the permit space to be entered, authorized entrants, attendants, and entry supervisors;
- The purpose of entry and date and authorized duration of entry;
- Means of detecting an increase in atmospheric hazard levels;
- Name and signature of supervisor who authorizes entry;
- Known hazards in the space and the measures to be taken to isolate permit spaces and to eliminate or control space hazards;
- Acceptable entry conditions;
- Atmospheric test results, date and time of test(s), and tester’s initials or signature;
- Name and telephone numbers of rescue and emergency services and the means to be used to contact them;
- Communication procedures and equipment to be used for maintaining contact during entry;
- Special equipment and procedures, including PPE and alarm systems;
- Any other information needed to ensure employee safety; and
- Additional permits, such as for hot work, that have been issued authorizing work in the permit space.
If you have employees or use contractors at a multiemployer worksite, all employers have responsibility for compliance with confined space requirements. If you rely on third-party rescue services, you first must ensure the rescue services can protect their own employees.
You must evaluate prospective emergency responders and select a provider that:
- Has adequate equipment for rescues, such as atmospheric monitors, fall protection, extraction equipment, and self-contained breathing apparatus (SCBA), for your particular permit-required confined spaces;
- Has the ability to respond and conduct a rescue in a timely manner based on the site conditions and to conduct a rescue managing the potential hazards specific to your confined space; and
- Will notify you in the event the rescue team becomes unavailable.
Your compliance begins with identifying confined spaces and their hazards and only allowing properly trained, equipped, permitted entrants to enter a confined space, as well as ensuring that conditions are monitored before and during entry, that an attendant maintains contact with entrants, and that you have planned rescue procedures and rescue personnel available.