Welding Confined Spaces. Question: Compare

Welding Confined Spaces. Question: Compare and contrast the confined space recommendations made by the American Welding Society with those of PDF Chapter 13. Fact Sheet 11 of the American Welding Society and Chapter 13 "Confined Space Entry" both address the potential hazards of working in confined spaces. The American Welding Society specifically focuses on hot work in confined spaces, whereas Chapter 13 offers a more general perspective of working in confined spaces. Both publications provide a clear definition of terms.

The American Welding Society defines confined spaces as areas with "limited space, entry or exit," or alternatively, areas with "poor ventilation" such as spaces with a possible buildup of toxic fumes. The Chapter on "Confined Space Entry" provides a slightly more nuanced definition with three components as follows. First, a confined space is "large enough to enable an employee to enter and perform assigned work," (p. 251). Second, a confined space "has limited or restricted means for entry or exit," (p. 251).

A third definition of a confined space is one that is "not designed for continuous employee occupancy," (p. 251). Furthermore, the chapter on "Confined Space Entry" adds a qualification for permit-required confined space. A permit-required confined space is one that "may contain a hazardous atmosphere, contains a material with the potential for 'engulfment' of an entrant," or could potentially trap the employee (p. 251). Therefore, the American Welding Society does direct the issues such as toxic atmosphere, which are related to the permit-required confined space.

The two publications outline their recommendations about confined spaces differently, with those of the American Welding Society stated much more succinctly than those in "Confined Space Entry." The recommendations themselves are relatively similar. Both publications recommend as a first step the identification of all confined spaces, and the posting of appropriate warning signs. Similarly, both publications suggest the issuance of special permits for entry. Ventilation is underscored as being critical to confined space safety in both documents.

Oddly, though, Chapter 13 is less emphatic about ventilation requirements than the American Welding Society. The American Welding Society repeatedly mentions the importance of good ventilation in confined spaces. One issue that the Chapter 13 text includes is whether or not entry into the confined space is actually required or not. The American Welding Society publication is written under the assumption that entry in the confined space is required. Testing air quality is an important suggestion issued by both Chapter 13 and the American Welding Society.

Chapter 13 recommends at least 19.5% oxygen by volume, and a flammable range of less than ten percent of the lower flammable limit (p. 255). Toxic air contaminants should be "absent" according to Chapter 13. Such absolute measures are absent from the American Welding Society document. In fact, the American Welding Society admits that potential exposure to toxic air contaminants like fluorine, zinc, lead, cadmium, mercury, and beryllium is inevitable. The American Welding Society document is geared for a specific industrial sector, whereas Chapter 13 is written for a more general occupational safety audience.

Both organizations agree that the means by which to shut off potential hazards like gas emissions should ideally be located both inside and outside of the confined space, but only the American Welding Society emphasizes this issue by reiterating it. The Chapter 13 places more burden of responsibility on the watcher on the outside of the confined space. The American Welding Society takes into account the reality that a watch person might not be qualified or available to take such measurements.

Either way, air quality testing is an imperative according to both the American Welding Society and Chapter 13. Workers must work in teams, and both publications acknowledge the need for partners such as watchers working immediately outside the space. The American Welding Society takes for granted the training programs that would be in place by the time an employee was even eligible for placement in a confined space, but the authors of Chapter 13 do not take this issue for granted. Rescue and contingency plans are mentioned by both publications.

A rescue crew should be an integral feature of the workforce where confined spaces are an issue. Exits should not be blocked, and specialized equipment such as breathing devices are actually listed as being required by law. Protective gear is listed as being crucial by both publications. The most noticable difference between the American Welding Society and Chapter 13 is that the former focuses more on the possible added hazards of heat. For instance, the American Welding Society suggests that flammables be protected during any welding activities in a confined space. 2.

Chromium and Nickel in Welding Fume. Question: Using other web resources, compare and contrast the AWS recommendations for controlling exposure to Chromium and Nickel welding Fumes with those of other organizations. If you were the safety professional reviewing the hazards for manual welding involving exposure to these substances, what controls would you establish? Fumes from welding compounds vary but usually include chromium compounds and nickel.

According to the Canadian Center for Occupational Health and Safety (2010), "welding fumes are a complex mixture of metallic oxides, silicates and fluorides." The American Welding Association does not provide a full spectrum of the type of metals and thus, the types of fumes the worker might be exposed to in different settings. This is a crucial difference. Moreover, the vapors from welding contain solid particulates. The presence of solid particulates affects the efficacy of the protective gear and this is important to mention in safety literature.

The American Welding Society does mention that welding fumes are potentially cardinogenic but gives only a broad overview of what those fumes (or particulates) are composed of. Furthermore, the Canadian Center for Occupational Health and Safety also includes as potentially hazardous the coatings and residues on the items being welded -- not just the welding materials themselves. Such information is lacking from the American Welding Society.

In any case, the immediate effects of exposure to the chromium and nickel compounds include nausea, headache, dizziness, respiratory irritation, and in some cases skin rash (American Welding Society Fact Sheet 4, 2003, p. 1). Controlling exposure to chromium and nickel welding fumes involves a series of preventative and corrective steps. Preventative steps include removing culprit coatings (Canadian Center for Occupational Health and Safety 2010). The American Welding Association stresses the importance of good ventilation, because nickel and chromium compounds are known carcinogens.

Air sampling should be used in conjunction with good ventilation, and exposure should be as "low as possible," (American Welding Association, Fact Sheet 4, 2003, p. 2). The Canadian Center for Occupational Health and Safety (2010) indicates the source materials for chromium as "most stainless-steel and high-alloy materials," as well as "welding rods" and "plating material." Similarly, the materials from which nickel fumes may emit include "stainless steel, Inconel, Monel, Hastelloy and other high-alloy materials, welding rods and plated steel," (Canadian Center for Occupational Health and Safety 2010).

The American Welding Society (2003) does not mention such detail, which could be valuable for small businesses. Likewise, the Canadian Center for Occupational Health and Safety (2010) notes the potential and specific health hazards associated with both nickel and chromium. For chromium, the health hazards include "increased risk of lung cancer," especially with hexavalent chromium (Canadian Center for Occupational Health and Safety 2010). The American Welding Society (2003) does note that hexavalent chromium is carcinogenic but does not mention which specific welding materials might include it.

Controlling exposure starts with education, which is why I would make sure to list in plain language which materials (including brand names) are potential culprits: which include hexavalent chromium, for instance. Of course, I would mention the importance of protective breathing gear and ventilation but I would be more specific than the American Welding Society. I would note which specific types of protective gear, what specific levels of fumes are appropriate, and most importantly, how to design workspaces that provide for good ventilation.

The United States Department of Labor Occupational Safety and Health Administration (OSHA n.d.) provides unequivocal outlines and guidelines for preventing exposure to nickel and chromium fumes emitted during the welding process. OSHA (n.d.) includes, in addition to guidelines for ventilation and protective equipment, advice about appropriate medical surveillance. This latter matter is a critical omission from the document published by the American Welding Society (2003). 3. Thoriated Tungsten Electrodes.

Question: What are the hazards of thorium? What is the source of thorium exposure during use of thoriated tungsten electrodes? What controls would you specify? Who would have to implement the AWS recommended controls for thorium exposure? According to the American Welding Society (2003), thorium is "a radioactive material that can pose health and environmental risks at elevated exposure levels," (Fact Sheet 27, p. 1). Thorium emits mainly alpha but also beta and gamma radiation (American Welding Society 2003).

The dust particles created by welding with thoriated tungsten electrodes, when inhaled, are therefore a type of radioactive exposure and must be controlled for in the workplace. Unfortunately, thoriated tungsten electrodes "make good welds" and "are long lasting and quite easy to use," (American Welding Society 2003). One benefit of using thoriated tungsten electrodes is.