Confined Spaces: Protecting Against the Dangers

By Evan Gurley

The Occupational Safety and Health Association cited a California company in 2013 after a 40-year-old worker was killed while inside a concrete mixer chipping away buildup. The company received citations for failing to identify the hazards of working within the confined space and failing to train its workers about confined space hazards. The six serious violations and one general violation with penalties totaled $50,400. This is just one account of an accident that could have been avoided with proper hazard identification and adequate training. According to OSHA, that wasn’t the only confined space fatality in 2013. OSHA estimates that about 90 deaths involving confined spaces occur every
year. 

Confined space signs remind employees of the proper procedures and precautions to take before entering. (NPCA file photo)

Confined space safety: What you need to know

Many precast workplaces contain spaces that are considered to be confined because the configurations hinder the activities of employees who work in them. In many instances, employees who work in confined spaces also face increased risk of entrapment, engulfment and hazardous atmospheric conditions. Confinement itself may pose entrapment hazards and may keep employees closer to hazards – such as machinery components – than they would be otherwise.

As outlined in OSHA 29 CFR 1910.146, a confined space is:

• Large enough for an employee to enter fully and perform assigned work.
• Not designed for continuous occupancy by the employee.
• Limited or restricted with regards to entry or exit.

Confined spaces at precast plants may include vaults, tanks, storage bins, pits, cement/fly ash silos, storage vessels and other similar areas. The terms “permit-required confined space” and “permit space” refer to spaces that meet OSHA’s definition of a confined space and contain additional health or safety hazards. For this reason, OSHA requires workers to have a permit to enter these spaces.

A permit-required confined space also contains one or more of the following characteristics:

• Potential to contain a hazardous atmosphere.
• Potential to engulf someone who enters the space.
• An internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section.
• Other serious physical hazards such as unguarded machines or exposed live wires.
• Other recognized serious safety or health hazards.
• Is immediately dangerous to life or health.

This means that if the space has either real or potentially hazardous atmospheres (e.g. oxygen deficiency, oxygen enrichment, presence of toxic vapors/fumes, presence of explosive vapors/fumes), presents engulfment by material or contains physical hazards (e.g. unguarded moving machinery, narrowing passages, excessive heat, excessive noise or other hazards that pose a serious threat), there must be additional safety steps taken to ensure the safety of anybody accessing that space.   

Safety precautions you should consider with permit-required confined spaces:

• Do not enter without being trained and without having a permit.
• Review, understand and follow the precaster’s procedures before entering and exiting.
• Before entry, identify any physical hazards.
• Before and during entry, test and monitor for oxygen content, flammability, toxicity or explosive hazards as necessary.
• Use fall protection, rescue, air monitoring, ventilation, lighting and communications equipment according to entry procedures.
•  Maintain contact at all times with a trained attendant either visually, via phone or by two-way radio. This monitoring system enables the attendant and entry supervisor to order you to evacuate and to alert appropriately trained rescue personnel to rescue entrants when needed.

What precasters need to do to comply

OSHA 29 CFR 1910.146 contains best practices and procedures to protect employees in the precast industry from the hazards of entering permit-required confined spaces.

Precasters must evaluate all workplaces to determine if spaces are classified as confined spaces and/or permit-required confined spaces. If a workplace contains permit spaces, the precaster must inform exposed employees of its existence, location and the hazards it poses. This can be done by posting danger signs such as “Danger: Permit-Required Confined Space – Authorized Entrants Only.” If employees should not enter and work in permit spaces, precasters must take effective measures to prevent them from entering. The precaster must develop a written permit-confined space program and make it available to employees or representatives.

Under certain conditions described in the standard, the precaster may use alternative procedures. For example, if a precaster demonstrates with a monitoring device and inspection data that the only hazard is an actual or potentially hazardous atmosphere that can be removed using continuous forced air ventilation, the precaster may be exempted from some requirements such as permits and attendants. Additional considerations include:

• Written programs. Any precaster who allows employee entry into a permit space must develop and implement a written program for the space.
• Controlling hazards. A precaster’s written program should establish the means, procedures and practices to eliminate or control hazards necessary for safe permit space entry operations.
• Equipment for safe entry. In addition to personal protective equipment, other equipment that employees may require for safe entry includes the following: testing, monitoring, ventilating, communications and lighting equipment, barriers and shields, ladders and retrieval devices.
• Detection of hazardous conditions. If hazardous conditions are detected during entry, employees must immediately leave the space. The precaster must evaluate the space to determine the cause of the hazardous atmosphere and modify the program as necessary.
• Entry permits. A permit, signed by the entry supervisor, must be posted at all entrances or otherwise made available to entrants before they enter a permit space. The permit must verify that pre-entry preparations outlined in the standard have been completed. The duration of entry permits must not exceed the time required to complete an assignment. 
• Cancel entry permits. The entry supervisor must cancel entry permits when an assignment is completed or when new conditions exist. New conditions must be noted on the canceled permit and used in revising the permit space program. The standard requires that the employer keep all canceled entry permits for at least one year.
• Worker training. The precaster must provide proper training for all workers who are required to work in permit spaces. After the training, the precaster must ensure that the employees have acquired the understanding, knowledge and skills necessary to safely perform their duties. Additional training is required when job duties change, a change occurs in the permit space program or the permit space operation presents a new hazard and an employee’s job performance shows deficiencies.
• Assign duties and emergency procedures. Personnel duties and emergency procedures should be established and assigned to ensure everyone knows their role and the proper procedures required in case of an emergency.

OSHA update: Final rule issued includes construction workers

In May, OSHA published a final rule to increase protections for construction workers in confined spaces. In August, the standard went into effect. The new subpart replaces OSHA’s one training requirement for confined-space work with a comprehensive standard that includes a permit program designed to protect employees from exposure to many hazards associated with work in confined spaces, including atmospheric and physical hazards. The final rule is similar in content and organization to the general industry confined space standard, but also incorporates several provisions for the proposed rule to address construction-specific hazards, account for advancements in technology and improve enforceability of the requirements. 

OSHA last issued rules addressing work in confined spaces in 1993; however, those provisions applied only to general industry work. A single training provision, issued in 1979, applies to confined space work in construction. 29 CFR 1926.21(b)(6) provided limited guidance, instructing employers to train employees as to the nature of the hazards involved, necessary precautions to be taken and use of protective emergency equipment.

Manholes, crawl spaces, tanks and other confined spaces are not intended for continuous occupancy. People working in confined spaces face life-threatening hazards including toxic substances, electrocutions, explosions and asphyxiation. In 2014, two workers were asphyxiated while repairing leaks in a manhole, the second when he went down to save the first, which is not uncommon in cases of asphyxiation in confined spaces.

“In the construction industry, entering confined spaces is often necessary, but fatalities like these don’t have to happen,” said Secretary of Labor Thomas E. Perez. “This new rule will significantly improve the safety of construction workers who enter confined spaces. In fact, we estimate that it will prevent about 780 serious injuries every year.” 

The rule will provide construction workers with protections similar to those who work in manufacturing and general industries, with some differences. These include requirements for: identifying confined spaces and the hazards they may contain, allowing employers to organize the work to avoid entry into a potentially hazardous space, removing hazards prior to entry to avoid employee exposure, restricting entry through a permit system where employers cannot remove the hazard, providing appropriate testing and equipment when entry is required and arranging for rescue services to remove entrants from a confined space when necessary.   

The final rule affects establishments in several sectors of the construction industry, including work involving buildings, highways, bridges, tunnels, utility lines and other types of projects. Also potentially affected are general contractors, specialty-trade construction contractors and employers engaged in some types of residential construction work. 

Evan Gurley is a technical services engineer with NPCA.