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<<Stakeholder Meetings

Disclaimer: This summary consists of informal notes compiled by OSHA notetakers at the designated stakeholder meeting. They are not verbatim records and are intended merely to summarize the major points raised at the meeting. All issues related to a proposed rule for silica are still being discussed within the Agency and with interested stakeholders; no final decision on any issue has been reached.

SESSION 2 - September 15, 1999
1:30 p.m.-5:00 p.m.


The format of the stakeholder sessions followed the questions in a stakeholder document that is also available on the Web page. There were four general areas of discussion: scope, controlling exposures to crystalline silica, monitoring and sampling, and health screening and surveillance.


The OSHA panel began the conversation about silica regulation by stating that although the Agency is open to discussion on any issue related to the rulemaking, there are at least 300 deaths reported every year from silicosis, and that about 2,000 inspections have been done under the Agency's Special Emphasis Program (SEP). The panel asked stakeholders to address the two main issues: Which industries are affected and should therefore be covered by the rule? Which forms of crystalline silica should be covered?

A cast metal foundry stakeholder questioned the need for a standard by stating that there has been a decrease in the number of cases of silicosis. He further said:
  • Deaths were high 20 years ago, but how far do we go to reduce 10 to 20 deaths a year, especially when deaths occur at 70, 80, 90 years of age?
  • Is there a need for a lower PEL that would economically endanger an industry?
  • National Institute for Occupational Safety & Health (NIOSH)'s SENSOR Project shows 105 deaths from silicosis in 10 years in Ohio, and in two-thirds of the cases the individuals were over 70 years old.

The OSHA panel explained that before the Agency can regulate:
  • It must demonstrate a significant risk, which the courts have defined for serious health effects, such as cancer, as a risk that would cause death in no more than one per 1,000 employees over a working lifetime.
  • OSHA must also demonstrate that the regulation is technologically and economically feasible.
  • Office of Management and Budget (OMB) reviews risk and feasibility determinations to ensure that OSHA regulations are cost effective and minimize impacts on affected industries.

An aluminum foundry stakeholder asked why OSHA cannot address current overexposure cases through increased enforcement efforts. Reducing the PEL will penalize complying companies, while companies who have made no effort to comply will still not comply. It's not fair.

The OSHA panel responded that the current PEL will continue to be enforced in the interim, but it appears that we still need to reduce the PEL to reduce the risk.

A railroad union stakeholder said that ballast workers--who maintain track with gravel and rock--are dying. They are developing silicosis and dying, or being disabled, as young as age 40. He welcomed OSHA's efforts to reduce the PEL. Also, the International Agency for Research on Cancer (IARC) has labeled crystalline silica as a carcinogen.

A transportation and construction stakeholder said:
  • He is unaware of significant risk data, and would be interested in seeing that data.
  • His industry wants a separate standard for construction.
  • It is hard for many small contractors to understand a large, complex standard.
  • Employment is usually short term, and this makes training, medical tests, and record keeping burdensome.

A concrete industry stakeholder requested risk assessment data for that industry.
  • He asked if the risk of silicosis were greater than one person in every 1,000.
  • He said his company kept material under sprinklers as required by DOT regulations.
  • It costs between $2,000 and $3,000 for exposure monitoring in a precast plant.
  • He would like to see an incentive program for those who comply at the current PEL.
  • Most of the industry now have automated plants, and firms already have to keep a cleaner environment than they did 30 years ago.

A gypsum stakeholder asked:
  • Can we get a time frame for making the risk assessment data available?
  • Is there is any possibility that the data do not support a rule?
  • If an industry can show it has no silica problem, can it be exempted?

The OSHA panel responded:
  • In many cases, individual employers may have exposures that are too high and therefore have employees at high risk; however, they may not see any actual cases if they have few employees.
  • In addition, there may be a long latency period for silicosis to develop; in many cases it may not be seen until after retirement.
  • Nevertheless, the Agency is interested in receiving all information on exposures, risk, and health outcomes.
  • For silica-related diseases, with their long latencies, it would not be surprising for many employers, especially those with few employees, not to have seen a case.
  • If an industry determines that exposures are low (less than the applicable PEL), they would already have complied, and would be relieved of many obligations.
  • Regarding a request for separate standards for the construction and maritime industries, the OSHA panel said that providing specific provisions in an all-inclusive standard (called "tiering") is preferable to ensure that construction and maritime do not get left behind.
  • Health risks for this standard are based on observed serious health effects on human, not animal, data.

A stakeholder from the Industrial Safety Equipment Association asked about outreach and workshops, and whether OSHA had looked at all industries. The OSHA panel replied that the data on silicosis show clusters in specific industries--for example, abrasive blasting and foundries. However, cases are found in many industries.

Regarding abrasive blasting, a NIOSH representative said:
  • Personal protective equipment practices are not consistent.
  • People have died from acute silicosis in their 20s, 30s, and 40s.
  • There was a case of acute silicosis in a 21 year-old worker, but the case was never reported in the state of Indiana, and as a result, there was no opportunity for intervention.

A construction industry stakeholder wanted assurance that the Agency would provide a cost-benefit analysis geared to the construction industry, and noted that the construction industry cannot afford to lose workers as a result of a standard they are not yet certain will be effective. This stakeholder was concerned that the rulemaking was premature because effectiveness of the Special Emphasis Program (SEP) has not been addressed.

A brick manufacturing stakeholder said that exposures are very high in that industry, with 25 to 50 percent of workers exposed above the current PEL, and yet the rate of silicosis is very low in the industry. Clay encapsulation may be the explanation for this low silicosis rate. He then asked:

What information can our industry provide that will help assess the risk of encapsulated silica?

The OSHA panel responded that the Agency must look at risks from 45 years of exposure with predicted frequencies of health outcomes (silicosis) of one per 1,000 or greater. Also, the Agency must look at feasibility research focused on industries or operations. One might not see that risk in a particular study or have data on a given industry segment. The OSHA panel added that as well as any direct data on exposures and health outcomes, both animal and in vitro studies describing biological activity would be helpful.

The brick manufacturing stakeholder responded that the dusty trades would have neither the time nor the resources to conduct such studies.

A stakeholder of clay encapsulated products stated that a big issue is correctly identifying the polymorph of silica and offered the following:
  • IARC took a small step in acknowledging the differences.
  • OSHA has a laboratory method to identify the form and NIOSH has 7500 and 7601 lab analytical methods.
  • Many clays actually have amorphous rather than crystalline silica. Amorphous silica may also encapsulate crystalline silica. Opal is an amorphous form of silica, but it is often mistakenly identified as a crystalline form.
  • It is necessary to distinguish between aged silica and freshly fractured silica.
  • Water and organic compounds can change one form of silica to another.
  • The human body does not react to aged quartz in the same way as it does to newly fractured quartz.
  • Grinding and purification processes may create a reactive surface.
  • The silica used in animal experiments has been broken to reduce its size before it is injected into the test animals. This yields results different from those one would obtain from real environmental exposures. Thus, many animal studies cannot be accurately interpreted because they have not correctly identified the materials.
  • If crystalline silica is carcinogenic, why is there no rampant outbreak of cancers from environmental exposures?

A NIOSH representative discussed recent publications by Wallace, Castranova, and Lawrence that address health risk issues of crystalline silica. He further stated:
  • That epidemiological studies, not animal studies, are needed for regulatory purposes. He posed 2 questions:
  • How much time must pass before silica is no longer "freshly" fractured?
  • Although clay coated silica may act in vitro, how much time would pass before the clay surface or coating was removed?

A foundry representative described their typical operations as consisting of mixing, mold making, shaking out, chipping, and grinding, he said:
  • New foundries could meet regulatory requirements of a new PEL, but the older ones could not comply without spending millions of dollars.
  • He asked whether NIOSH had any additional information about the 21 year-old with acute silicosis. NIOSH responded that they did not.
  • The foundry stakeholder stated that he would like to see foundries treated separately from other industries.

A cast metals stakeholder stated:
  • There was no evidence of silicosis in his foundry after many years of operation.
  • His company does the largest metal castings and could not meet the new standard with engineering controls in some operations.
  • They can't comply with the current PEL in some operations now.
  • The cast metals industry in Ohio does not perceive a risk from silica in its workplaces.

A railroad union stakeholder said:
  • Feasibility may be key to addressing differences across industries. In the railroad industry there are some feasible methods to control exposures to silica. One example of such a method is the design of a watering tower.
  • With respect to encapsulation, clay encapsulated products are ground. The grinding action could remove the coating and result in exposure to freshly fractured silica.

A foundry stakeholder said one has to re-evaluate and rethink a process to find a way to control exposures. His foundry, for instance, has eliminated abrasive blasting operations. Because such a high energy process tends to fracture silica excessively, which leads to higher concentrations of free radicals on the newly fractured silica surface, one needs to look at the energy of the process and the free-radical concentrations.

A gypsum stakeholder asked if other diseases, such as bronchitis and other pulmonary diseases, are going to be covered, and whether the studies are weighted by scientific value.

The OSHA panel responded that the Agency is looking at the data on other diseases, such as kidney and pulmonary diseases, but is not necessarily doing risk assessments on them. The Agency will write or review risk assessments on silicosis and lung cancer. In response to the question concerning how OSHA selects or weighs the epidemiological studies, the OSHA panel explained that it decides on the best available evidence for risk assessment and relies on that. The Agency evaluates each study for the quality of the exposure information, the size of the cohort, and the relevance of the study. The Agency does not generally conduct meta-analyses.

A gypsum stakeholder then asked how OSHA regulates when studies suggest health effects at different exposure levels.

Does the Agency take an average, or use the study with the lowest exposure level?

The OSHA panel responded that it hopes to get studies with similar exposure levels. OSHA has averaged studies at times in the past, but there is no general methodology because of variation in the type of health effects, reliable studies, and data available.

A stakeholder noted that there is a legislative requirement to use consensus standards (OMB Circular A119). The OSHA panel responded that the Agency is interested in using consensus standards, but can only use them when they are consistent with the OSH Act and its interpretations by the courts.


The OSHA panel asked stakeholders about the use of engineering controls, exposure monitoring and health screening.

A brick manufacturer said that industry has trouble controlling dust to 50 micrograms per cubic meter (50 ug/m3).
  • Wet methods are not good because moisture content is critical in the production process.
  • She was concerned about the use of respirators because it gets to be 140-150 degrees Fahrenheit around the kilns. They use dust masks now, and are uncomfortable; a half face or full face mask respirator would be too hot.
  • This is one of the oldest U.S. industries, with many plants more than a 100 years old. There are about 100 facilities that manufacture brick, but 95 percent of the firms are small employers. The largest 3 or 4 companies supply 50-60 percent of the market. A new standard could threaten to put the small companies out of business.

A foundry stakeholder stated:
  • Engineering controls do not work well for controlling employee exposures while working on large castings.
  • Foundry operations obviously involve the very high temperatures of molten metals, which make wet methods infeasible for sand used in molds.
  • When chipping or grinding inside castings, engineering controls don't work.
  • Small companies cannot afford expensive employee exposure monitoring and medical screening tests.
  • A lower PEL will increase the use of respirators, which workers will resist.
  • Alternatives to sand, such as Green Diamond, cost five times more than silica and do not give the same casting finish. This means the metal requires additional grinding.
  • This industry, currently in a tight labor market, already has huge problems keeping employees without discouraging them from accepting employment by requiring them to use respirators.

Another foundry stakeholder, who has about 400 employees split between three foundries, said:
  • Workers go home to their farms after work and may have additional silica exposure from doing farm work.
  • A 3 year-old plant with the best equipment and machinery is already wearing out due to the abrasiveness of silica.
  • A lower OSHA PEL will impact small foundries like recent EPA regulations have done.
  • Two thousand dollars is a lot of money for a small business to pay for one local exhaust ventilation (LEV) system or a round of exposure monitoring.
  • A new regulation will cause small foundries to close, bringing hardship to employees as well as to entire small towns.
  • In some states, such as Texas, foundries have been closing due to state environmental regulations.

Another stakeholder continued:
  • We screen every year (X rays and pulmonary function tests (PFT)), and we have seen no silica-related problems in 10 years. (The cost of medical testing is $150 per person, including X ray, PFT, hearing, and basic physical.)
  • This medical testing has not found a case of silicosis, although lung cancers have been found among smokers.
  • Compressed air is not allowed for cleaning--that puts dust back in the air.
  • Many foundries conduct quarterly monitoring, getting different results from day to day, depending on the product being made.
  • They pay large fees to industrial hygienist consultants who sometimes hook up equipment backwards and do not know how to sample. Such testing would obviously result in false reports. Small foundry employers may not know how to find a good industrial hygienist who has experience with silica. Similarly, we have seen OSHA compliance officers make mistakes in sampling.
  • Many foundries do not have resources to perform monitoring in-house.
  • Also, we do not want to waste sand, and so do not want it in the air for this reason as well as the health risk for employees.

A railroad union stakeholder reported that respirators get clogged or employees take them off, and added:
  • Is there a way to add incentives for engineering controls? Engineering controls have many benefits; for example, you get better visibility by reducing the dust.
  • In training, the union focus is on engineering controls whereas the company emphasizes personal protective equipment (PPE).
  • Employee exposure monitoring is infrequently performed in the railroad industry.
  • With respect to regulated areas, the employees working in equipment cabs are protected, but their assistants working near the equipment are not, thus, a regulated area is needed.

In response to the OSHA panel's question about exposures in new construction, a transportation construction stakeholder stated:
  • Exposures are in cutting, jack-hammering, grading, grinding, sub-surface work, and especially, in repair work. The stakeholder was not sure that employee monitoring is frequently conducted in these operations.
  • Wet methods are sometimes good, but they can't always be used--on elevated platforms or in freezing weather, for example.
  • Respirators are too hot in the heat of the day. Also, workers' vision can be obstructed by respirators, so working near traffic could be a danger/problem.
  • When the sludge dries, whoever is present--employees or families-is exposed to dry dust.
  • There is a huge demand for qualified employees in our industry; we value them. Most laborers are contracted for a part of the job or a task, and then they are gone.
  • Today, the permanent employees on a construction site are generally supervisors.
  • Employers in this industry haven't seen the health risk.

An automotive foundry stakeholder spoke:
  • If OSHA is specifying monitoring and analytical methods, the Agency should focus on equipment accuracy. Precision does not have anything to do with accuracy. He expressed concern that an action level would be used as a PEL.
  • With respect to health surveillance, he opposed reporting to NIOSH unless accompanied by a complete occupational/vocational history. What does OSHA mean by "Medical Surveillance?"

The OSHA panel explained that exams are provided to evaluate employee health (employee health screening); providing information to NIOSH would be medical surveillance.

A gypsum stakeholder stated that using the Certified Industrial Hygienist (CIH) certification as a criterion for conducting monitoring or assessment is too broad.
  • CIHs may not have sufficient experience with silica. You need a way to qualify people as capable of monitoring for silica--for example, NIOSH training.
  • They once had their product tested by a highly regarded company. The results showed cristobalite of 36 ug/m3. The lab was wrong. The sample was re-analyzed and their report corrected to show no cristobalite. But the company IH had the industrial hygiene expertise and was able to catch the mistakes.

The OSHA panel responded that cristobalite usually raises flags in a laboratory.

An automotive stakeholder said that his company once generated a known amount of dust, and provided a sample to a lab. The lab followed general practices, but still came out with low exposure measurements due to interferences. Overloading and interferences have both been problems with sample analysis. The total cost of exposure monitoring in his plant was $6,500.

The OSHA panel said that it would like to write a standard that would improve the quality of the analytical results. It is a complicated issue.

The gypsum stakeholder responded that after looking at lots of alternatives, one could not come up with anything better than OSHA's current lab method.

An automotive industry stakeholder remarked that the stakeholder meetings and the Special Emphasis Program (SEP) were a good first step. He asked about status and data from the SEP. The OSHA panel responded that it had received requests from the American Foundrymen's Society and from glass manufacturers for data. The Agency is conducting a computer run this month and analyzing case files. Stakeholders can E-mail Paul Bolon [] to enquire about the availability of data.

An automotive stakeholder spoke:
  • Can there be proactive stakeholder meetings to achieve compliance with the current PEL?
  • If the PEL is lowered, especially to 50 ug/m3, the proactive industries want some credit for effort. Process modifications have been done. They have installed many engineering controls, but also must supplement with respirators, and even air-supplied respirators, where necessary. They would have a problem complying if engineering controls were the only control method. The automotive industry would like a regulation where PPE supplements engineering controls. Also, they do not want to monitor several times if it is not useful. He suggested referring to ASTM EO 1132, exposure to crystalline silica 1989, 1993 (revised every three years).