Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Job Classification

In most duration tables, five job classifications are displayed. These job classifications are based on the amount of physical effort required to perform the work. The classifications correspond to the Strength Factor classifications described in the United States Department of Labor's Dictionary of Occupational Titles. The following definitions are quoted directly from that publication.

Sedentary Work Exerting up to 10 pounds (4.5 kg) of force occasionally and/or a negligible amount of force frequently or constantly to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and other sedentary criteria are met.

Light Work Exerting up to 20 pounds (9.1 kg) of force occasionally and/or up to 10 pounds (4.5 kg) of force frequently, and/or negligible amount of force constantly to move objects. Physical demand requirements are in excess of those for Sedentary Work. Light Work usually requires walking or standing to a significant degree. However, if the use of the arm and/or leg controls requires exertion of forces greater than that for Sedentary Work and the worker sits most the time, the job is rated Light Work.

Medium Work Exerting up to 50 (22.7 kg) pounds of force occasionally, and/or up to 25 pounds (11.3 kg) of force frequently, and/or up to 10 pounds (4.5 kg) of forces constantly to move objects.

Heavy Work Exerting up to 100 pounds (45.4 kg) of force occasionally, and/or up to 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Very Heavy Work Exerting in excess of 100 pounds (45.4 kg) of force occasionally, and/or in excess of 50 pounds (22.7 kg) of force frequently, and/or in excess of 20 pounds (9.1 kg) of force constantly to move objects.

Siderosis


Related Terms

  • Arc-welder's Disease
  • Siderosis Pneumoconiosis
  • Welder’s Lung

Differential Diagnosis

  • All other pneumoconioses
  • Antimony pneumoconiosis
  • Baritosis (barium)
  • Stannosis (tin)

Specialists

  • Preventive Medicine Specialist
  • Pulmonologist

Comorbid Conditions

  • Cigarette smoking
  • Other forms of pneumoconiosis

Factors Influencing Duration

Usually disability is not expected from siderosis.

Medical Codes

ICD-9-CM:
503 - Pneumoconiosis Due to Other Inorganic Dust

Overview

Siderosis is a type of occupational lung disease (pneumoconiosis) caused by the inhalation of dust or fumes containing iron or iron oxide particles. It is most commonly seen in arc welders and is also referred to as arc-welder's disease. Iron dust and fumes are also found in mining, steelmaking, iron or steel rolling, metal polishing industries, and in work with ochre pigments. The inhaled iron particles accumulate in the lungs, and while this collection of iron in the lungs is visible upon x-ray, it is usually not associated with inflammation or altered lung function. However, the harmlessness of the metal dust or fumes exposure has been questioned, and reports have been published associating siderosis with pneumonia, lung cancer, and pulmonary fibrosis, among other respiratory diseases.

Incidence and Prevalence: The Bureau of Labor Statistics estimates that there are 337,300 jobs in the U.S. as welders, cutters, solderers, and brazers, with an estimated growth of 50,000 by year 2020 (BLS). There are no incidence measures for siderosis in the US, but a study conducted in Poland found that siderosis was the third most prevalent form of pneumoconiosis after pneumoconiosis from coal dust and silica exposures, with an incidence rate of 0.7 per 100,000 workers (Antonini).

Source: Medical Disability Advisor



Causation and Known Risk Factors

Anyone working as a welder, cutter, solderer, or brazer is at potential risk of exposure from arc welding. Over time (usually 20 years or more), exposure to arc welding causes the accumulation of iron oxide in the lungs. Wearing appropriate personal protective gear is key to protecting one's health. A welding helmet can reduce exposure to harmful particulate matter by as much as 71% (Antonini).

Source: Medical Disability Advisor



Diagnosis

History: During a visit to the physician for an unrelated reason or during discussion of an abnormal x-ray, a history of repeated or prolonged exposure to iron or iron oxide dust or fumes will be disclosed. In individuals in whom lung siderosis is generating symptomatic and functional changes, see the pertinent topics, for example, Pneumonia, Lung Cancer, Pulmonary Fibrosis, or other respiratory medicine diagnosis.

Physical exam: Physical signs are usually absent, although abnormal breath sounds may be noted in rare cases. See also the pertinent respiratory medicine topics.

Tests: Chest x-rays may reveal a net-like (reticular) pattern or, in more severe cases, the presence of small opaque areas (micronodules). In the absence of respiratory complications associated with siderosis, pulmonary function tests (PFTs) to evaluate lung volumes, capacities, gaseous diffusion, and distribution are usually normal. Spirometry will be used to detect any restriction of normal lung expansion or obstruction of airflow. A peak flow meter will detect narrowing of the airways. Analysis of a sputum sample will reveal the presence of alveolar macrophages (a type of immune cell) and abnormal red blood cells containing non-hemoglobin iron particles (siderocytes). Arterial blood gases (ABG) will be done to assess the efficiency of oxygen and carbon dioxide exchange (gas exchange) in the lungs and the efficiency of gas absorption into the blood, ensuring that oxygen content in the blood is adequate.

Source: Medical Disability Advisor



Treatment

Siderosis is preventable but not treatable. Because it does not normally cause any symptoms or damage to body tissues, treatment is not required. Avoiding exposure to iron dust or fumes will prevent any further accumulation of particles in the lungs. In individuals with lung damage related to siderosis, treatment will be contingent on the particular complication.

Source: Medical Disability Advisor



Prognosis

Siderosis is usually a harmless (benign) disease. Most cases never produce symptoms of illness. In rare cases where lung damage does occur, avoiding further exposure to iron dust or fumes prevents progressive damage.

Source: Medical Disability Advisor



Complications

Complications do not generally occur, but may include pneumonia, lung cancer, and pulmonary fibrosis.

Source: Medical Disability Advisor



Ability to Work (Return to Work Considerations)

Because siderosis does not usually cause any symptoms, tissue injury, or reduced lung function, work restrictions and/or accommodations are not generally required. Personal protective clothing, masks, and welding helmets may be helpful in reducing exposure and preventing the condition from occurring.
For more information refer to "Work Ability and Return to Work," pages 309–310.

Risk: Individuals with symptomatic lung siderosis may benefit from reducing exposure to heavy fumes, dusts, and respiratory irritants, although a paper mask may be sufficient protection in most cases. More advanced mask systems as per OSHA guidelines should also be followed in certain industries.

Capacity: Capacity is typically unaffected by this condition. Cardiopulmonary exercise testing and pulmonary function tests, often with metabolic stress echocardiography (ECHO) testing, may help to confirm adequate oxygenation.

Tolerance: Tolerance is usually not a concern with this diagnosis. If the affected individual is obese and/or physically deconditioned, tolerance may be enhanced by ensuring compliance with any prescribed medication, verifying the absence of concurrent conditions such as anemia, and initiating a home exercise program to improve fitness levels.

Source: Medical Disability Advisor



Maximum Medical Improvement

1 day.

Source: Medical Disability Advisor



Failure to Recover

If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case.

Regarding diagnosis:

  • Has the diagnosis of siderosis been confirmed?
  • Have other lung diseases, such as stannosis (tin), baritosis (barium), and antimony pneumoconiosis been ruled out?
  • Has individual been exposed to other occupational air contaminants?
  • Does individual have an underlying condition that may impact recovery?
  • Is individual a tobacco smoker?

Regarding treatment:

  • Has individual been provided with protective clothing, mask, and welding helmet to reduce further exposure?
  • Has individual been advised to stop smoking?
  • Would enrollment in a community smoking cessation program be beneficial?

Regarding prognosis:

  • Has individual been provided with protective clothing, mask, and welding helmet to reduce further exposure when lung damage has occurred?
  • If lung damage has occurred, has individual received appropriate treatment and been advised to stop smoking?

Source: Medical Disability Advisor



References

Cited

"Welders, Cutters, Solderers, and Brazers." Bureau of Labor Statistics. 8 Jan. 2014. U.S. Department of Labor. 6 Nov. 2014 <http://www.bls.gov/ooh/production/welders-cutters-solderers-and-brazers.htm>.

Antonini, J. M. "Health Effects of Welding." Critical Reviews in Toxicology 33 (2003): 61-103.

Newman, Lee S. "Environmental Lung Diseases." Merck Manuals Online. Apr. 2008. Merck & Co., Inc. 6 Nov. 2014 <http://www.merckmanuals.com/home/lung_and_airway_disorders/environmental_lung_diseases/overview_of_environmental_lung_diseases.html?qt=environmental%20lung%20diseases&alt=sh>.

Talmage, J. B. , J. M. Melhorn, and M. H. Hyman, eds. Work Ability and Return to Work, AMA Guides to the Evaluation of. Second ed. Chicago: AMA Press, 2011.

Source: Medical Disability Advisor






Feedback
Send us comments, suggestions, corrections, or anything you would like us to hear. If you are not logged in, you must include your email address, in order for us to respond. We cannot, unfortunately, respond to every comment. If you are seeking medical advice, please contact your physician. Thank you!
Send this comment to:
Sales Customer Support Content Development
 
This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is published with the understanding that the author, editors, and publisher are not engaged in rendering medical, legal, accounting or other professional service. If medical, legal, or other expert assistance is required, the service of a competent professional should be sought. We are unable to respond to requests for advice. Any Sales inquiries should include an email address or other means of communication.