Closing in on the Confusion about Permit-Required Confined Spaces BYLINE: By John W. Hodgson , MS , CIH
Closing in on the Confusion about Permit-Required Confined Spaces
BYLINE: By John W. Hodgson , MS , CIH
Employers have great difficultly in properly interpreting OSHA's Confined Space Standard and for good reason. Even safety and health professionals sometimes struggle with the interpretation and implementation of this standard. Safety professionals often bypass some of these difficult areas by using sound safety and health practices to go beyond the standard's requirements. However, how can the many small employers who may not have a dedicated safety and health professional implement this standard properly? Unfortunately, the answer is, “Usually not very well!” The following information focuses on some of the decision making process for a simple permit-required confined space (PRCS).
Defining Confined Spaces
The first step is to determine whether space meets the definition of a confined space? The standard defines a confined space as a space that can be bodily entered, that has a limited means for entry or exit, and that is not designed for continuous human occupancy. Remember, a space has to meet all three criteria to be considered a confined space.
Notice that the hazards of the space are not directly addressed by the above definition. A pipe containing “really bad stuff” has only one 12-inch diameter opening. Although the hazard can be extreme, this space cannot be a confined space because it cannot be bodily entered. The opening is too small, even though an employee could put their head into the pipe. This type of space and many others can pose serious hazards that are outside the scope of this standard.
Oven Example
A small bake oven that is 7 feet wide by 7 feet deep by 8 feet high is used for curing powder-coated parts. The interior is completely open and it has a natural gas burner that heats this oven to its 380 degrees Fahrenheit operating temperature. The oven has a large door that is 5 feet wide by 7 feet high through which the employees manually roll the racks of parts. The door, once closed, cannot be opened from the inside. The oven is a confined space because it can be entered with the entire body, it has a restricted exit, and at 380 degrees, it is certainly not designed for continuous human occupancy. For clarity, continuous human occupancy means that the space could be occupied under operating conditions, not that it always has to be occupied.
The employer exclaims, “Who is going to enter the oven and then shut the door behind them?” An acceptable answer is to modify the door so that it could be opened from the inside. The oven would not have a restricted exit and it would not meet the definition of a confined space. For our purposes, it will remain as a confined space.
Is the oven described above a permit-required confined space (PRCS)? A permit space is a confined space that contains a potential or known hazard. It is important to remember that a PRCS cannot exist without being a confined space. A permit-space only has to contain one of the following hazards: atmospheric, engulfment, an internal configuration that could trap or asphyxiate an entrant, or any other recognized serious safety or health hazard. Lack of knowledge and acceptable practices common to safety and health practitioners, often leads to faulty hazard assessments.
The bake oven uses natural gas; therefore, there is the potential for a hazardous atmosphere. This could result from incomplete combustion resulting in carbon monoxide exposure or leakage of gas into the space. Hazards that are the result of engulfment and the internal configuration are not present. The oven does have another recognized serious health hazard: the high temperature. This oven meets the definition of a permit-required confined space (PRCS).
Permit-Space Entry
Employers must consider how the space is entered. The standard gives us three options: alternate entry procedure, (c)(5); reclassification, (c)(7); or a permit space program (d). Depending on the employer's entry procedure, it is possible to correctly enter this oven using any one of these options. To use the alternate entry procedure, the only hazard that can be present is an actual or potential hazardous atmosphere that can be controlled using only forced air ventilation. The alternate entry procedure also requires that the employer demonstrate that forced air ventilation alone is sufficient to maintain the space safe for entry and that the employer develop monitoring and inspection data to support this conclusion. Reclassification can only be done if all hazards are eliminated . If the (c)(5) or (c)(7) requirements cannot be met or the space has to be initially entered, then a complete permit space program must be used.
Hazard Control and Elimination
The proper application of the alternate entry procedure or reclassification can be a daunting challenge. It is essential to understand the difference between the terms “hazard control” and “hazard elimination.” For example, the proper lockout of electro-mechanical devices is considered hazard elimination. However, lockout of a single valve controlling any flowable material such as natural gas is considered hazard control, not hazard elimination. An “isolation” technique must be used to eliminate the hazard. The standard defines isolation and gives examples of isolation, such as blanking or blinding, misaligning or removal of pipe, and double block and bleed system.
Alternate Entry and Reclassification
Going back to the oven example, consider that the employer locks-out the gas valve to the burner, but does not allow the oven to cool. The alternate entry procedure cannot be used because a heat hazard, which is other than atmospheric, is present. If the oven is allowed to cool before entry, then the alternate entry procedure can be used. Cooling of the oven and using an isolation technique to eliminate the hazard posed by natural gas would allow the oven to be entered using reclassification. A common misconception is the idea of a permanent reclassification; this does not exist. Once the oven is put back into service, it becomes a PRCS. A proper evaluation of the space must always take place before any type of entry. In addition, each time the space is entered using (c)(5) or (c)(7) a written certification must be completed to verify the space is safe for entry or that all hazards are eliminated, respectively.
Conclusion
Proper implementation of the Confined Spaces Standard requires workplace assessment analysis, planning and evaluation. Many states provide free, safety and health consultation services to help small employers, and federal OSHA offers resources on its Web site, osha.gov. In some cases, the services of a professional in compliance programs may be needed to answer the most difficult questions about a particular confined space.
CM