MOS 5201 – Columbia Southern University

October 14, 2013

Introduction
When it comes to safety rules and regulations, there are many different sources to look for safety and health facts. In this paper we will be examining the safety and health facts for confined spaces, chromium and nickel in welding fumes, and thoriated tungsten electrodes, as they are presented in both the American Welding Society (AWS) safety and health fact sheets, as well as the course textbook, Occupational & industrial safety health management and engineering (2nd Custom ed.) and other official safety and health expert sources. It can be seen that there many similarities amongst safety regulations, as well as differences, depending on the topic at hand.

Confined Spaces
Confined Spaces are considered to be a very dangerous hazard for all industries. Cleaning, repair, or maintenance can often require entry inside confined spaces such as small rooms, pits, underground utility vaults, sewers, storage tanks, and so on, often where hot work will need to take place. Hot work in a confined space is characterized by limited space for entry or exit, and poor ventilation of air and other hazardous gases and fumes (Asfahl, Hammer, & Price, 2004/2001). OSHA 1910.146 specifies a permit-required confined space as an area that has one or more of the following characteristics: contains or has the potential to contain a hazardous atmosphere; contains a material that has the potential to engulf an entrant; has walls that converge inward or floors that slope downward and taper into a small area which could trap or asphyxiate an entrant; or contains any other recognized safety or health hazard, such as unguarded machinery, exposed live wires, or heat stress (OSHA). In comparing the recommendations from Asfahl, Hammer, & Price with those from the AWS Fact Sheets, it can be seen that AWS covers the essential guidelines such as ventilation, testing and monitoring the air quality, maintaining communications with worker inside, breathing device, and properly equipped and trained rescue (AWS, 2009). However, upon comparing this to those characteristics listed in the text, I believe there are a few guidelines that the AWS is missing. Based on the case studies presented at the beginning of the confined spaces chapter, there are many lessons to be learned from unwanted fatalities occurring at different worksites documented by OSHA through the years. Due to this concern, AWS is missing the concern of additional potential hazards on their list, which needs to be a priority before entry is permitted. For example, flammable/explosive atmosphere might exist. Lack of natural ventilation, unexpected release of hazardous energy, physical barriers or limitations to movement, dangerous concentrations of air contaminants are possibly expected. Therefore, issuance of a confined-space-entry permit is a core step to conduct confined space operation. All confined spaces should be tested by a qualified/certified person before entry to determine whether the confined space operation is safe or not. A confined-space-entry permit is a safety measure that certifies that a space with a potentially hazardous atmosphere has been evaluated and tested by a qualified person to makes sure all necessary protective measures have been taken to ensure the safety of the worker (Asfahl, Hammer, & Price, 2004/2001). Additionally, the AWS does not cover the classifications a, b, and c, of confined spaces that rate the oxygen content, flammability, and toxicity of the confined spaced.

Secondly, the AWS states that workers should use NIOSHA/MSHA (National Institute for Occupational Safety and Health/Mine Safety and Health Administration) approved breathing devices in terms of personal protective equipment necessary for respiratory protection in a confined space. However, the AWS did not comment on the other personal protective equipment that is necessary for proper confined space entry and work to be completed. PPE such as head protections, hearing protections, safety belts, lifelines, mechanical-lift devices, and ventilation equipment is covered in the course text as necessary equipment for confined space work. It is very important to wear/use appropriate personal protective equipment and clothing at all times to prevent confined space fatalities. Another important point covered by the course text was the use of signs to alert all personnel working near a confined space and at the entry of a confined space (Asfahl, Hammer, & Price, 2004/2001). This is not covered by the AWS and is very important to prevent additional hazard exposure, such as flammable materials being used near a confined space that could easily occur on a worksite without the proper warning signs in place.

Chromium and Nickel in Welding Fumes

Chromium and nickel welding fumes have different measures of exposure control depending on the individual organization and industry you are examining. Controlling exposure is important, no matter what the process, due to the fact that the fumes from welding processes can potentially contain compounds such as hexavalent chromium and nickel compounds (AWS, 2003). The important consideration in controlling exposure is that welding fumes will vary greatly depending on the individual welding process being performed. As stated on the Safety and Health Fact Sheet No. 4, the American Welding Society mentions basic guidelines to protect exposure, such as: keeping your head out of the fumes to avoid breathing them in, using adequate ventilation or exhaust to keep fumes out of your general breathing zone, and generally keeping exposure levels as low as possible. These seem like fairly obvious steps to me, so I have to think there are other safety measures that can be taken in establishing exposure controls. As the Occupational Safety and Health Administration (OSHA) outlines, all welding processes should have the additional control of requiring goggles or face shields for both face and eye protection, which will help to further limit the direct exposure of fumes to skin and tissue. In accordance with OSHA 1910.132, protective clothing must also be worn at all times to prevent regular skin exposure during welding operations. The hazard depends on the welding method, filler metals and base metals, ventilation, what the welding rod is made of, but it is for this reason that the AWS should develop some methods which can effectively protect the workers and get the jobs done without fatalities. It is additionally recommended by OSHA that in the case of chromium and nickel welding, where there is an increased danger of toxic fume production from the compounds created, that respirators be worn in addition to having proper ventilation for respiratory protection, due to the immediate and long term effects caused by the exposure to hexavalent chromium and other such compounds. This is another area where the AWS fact sheet recommendations differ from that of other organizations, because all the AWS states under long term effects is that there is “limited evidence” for the carcinogenicity of welding fumes and gases, however, according to the Electronic Library of Construction Occupational Safety and Health (eLCOSH), the long term effects of exposure to chromium and nickel welding fumes include asthma and cancer. Furthermore, chromium can cause sinus problems and holes between the nostrils, exposure evidence that is well documented and controlled (eLCOSH, 2010). OSHA has additionally upheld these findings and published the standards enforcing permissible exposure levels to limits exposure for hexavalent chromium to be 5 ppm in an 8 hour time period (OSHA). A certified industrial hygienist can perform exposure testing of workers to determine if either the permissible exposure level (PEL) or the action level are being exceeded. As mentioned previously, the recommendations from the AWS should be expanded to include some additional equipment to protect workers, such as respirators and clothing, as well as measures to reduce exposure, such as preliminary testing and revised welding processes.

Thoriated Tungsten Electrodes

Thoriated Tungsten Electrodes present a danger due to the component of Thorium, which is a radioactive chemical material, and therefore can present a variety of health and safety risks when a worker is exposed. Thorium is capable of emitting alpha particles as well as some beta and gamma radiation (ASW, 2003). Principal hazards from thorium in industry are inhalation of thorium dust, thoron gas, its decay products, exposure to external beta, and gamma radiation. Inhalation of welding fumes and gases can be dangerous to your health. The short-term effects of exposure to welding fumes include minor symptoms such as dizziness, nausea, dryness or irritation of nose, throat, or eyes. Continued inhalation of thorium particles over a longer period of time could cause loss of consciousness and death. The long-term effects of exposure to welding fumes can lead to siderosis (iron deposits in lung) and is believed to affect pulmonary function (OSHA).

The source of thorium exposure is during wide use of thoriated tungsten electrodes across various industries, due to the fact that they make good welds. Exposure can increase when it is necessary to use tungsten welding rods containing thorium, because they can produce measurable levels of airborne radioactive material as a result of volatilizing the tip during welding, or grinding rods to put a point on the electrode prior to use. There are several controls that I would specify in order to limit the exposure to thorium in the work place. First, eliminate the hazard by considering the use of thorium-free tungsten electrodes or other similar welding techniques. Second, maximize ventilation during the welding and grinding process to maintain a healthy breathing zone that does not contain hazardous levels of particles or fumes. A third measure of control would be to wear protection equipment for the face/head, such as a mask, to help minimize exposure to fumes and particles while welding and grinding. Additionally, as with all potential hazards, it would be beneficial to have welders receive training in safe operations prior to beginning welding or grinding operations on the work site. Proper instruction in the use of personal protective equipment is important to review as well. Fifth, following the Material and Safety Data Sheet (MSDS) present for the chemicals/substances workers are being exposed to is an equally important control measure on the job. And lastly, a hazard assessment is an important part of evaluating any potential hazard, and thoriated tungsten electrodes in welding are no exception. A hazard assessment can help to evaluate and potentially reveal elevated exposure levels during the course of working with thoriated tungsten welding rods, giving necessary reason to review all of the current processes and ensure that exposures are appropriately controlled. Implementation of the AWS recommendations should be applied to welders, industrial hygienists, safety managers and supervisors.

References

American Welding Society (AWS). (2003-2009). Safety and Health Fact Sheets (No. 4, 11, 27). Retrieved from: http://www.aws.org/technical/facts/

Asfahl, C. R., Hammer, W., & Price, D. (2004/2001). Occupational & industrial safety health Management and engineering (2nd Custom ed.). New York, NY: Pearson Custom Publishing.

Electronic Library of Construction Occupational Safety and Health (eLCOSH). (2007).
Hexavalent Chromium [Data file]. Retrieved from: http://www.elcosh.org/record/document/143/d000946.pdf Occupational Safety and Health Association (OSHA). (2009). Hexavalent Chromium: Exposures and Controls. Retrieved from: https://www.osha.gov/SLTC/hexavalentchromium/exposure.html