RESPIRABLE SILICA DUST MONITOR

How to manage a health risk

Faulty wiring cited in early investigation of 6-year-old’s electrocution at MGM National Harbor

I captured this quote (source unknown) from a great analysis of the tragic accident noted above by the Washington Post, "The builders nondelegable responsibility for actual compliance not merely regulatory approval has to be emphasized".  Another quote I have carried with me, "Transfer of risk is a fundamental source of imperfection in markets".


Over the years I have seen several safety professionals in highly visible roles lament the lack of progress on the Health side of occupational Safety & Health.  A key contributor to that sense of discouragement is the lack of data or connective tissue identifying work-related disease and then placing that "case" where it belongs.


There is so much to say on this but let me pull on one string.  How well are exposures to hazardous chemicals characterized in the construction industry?  Pick any random commercial construction company and ask them for their employee exposure records for respirable silica, lead(Pb), welding fume, etc..  Take any random 55 yr old construction employee and get a work history of their past employers and jobs.  How many persons fall to a disease that is work-related?  How many lung cancer, COPD or heart disease cases can even Sherlock Holmes track back to the cause and culprit.  Is there a cacophony of undetected work-related disease or has work-related disease been snuffed out?  What do we as a society do if someone is diagnosed with a pneumoconiosis but there is no exposure data to the hazardous chemicals the employee had been exposed to over a working lifetime?**  I have a pretty good idea that the mining industry and MSHA have a decent handle on this question.  I know the State of Michigan has a pretty good idea of the silicosis landscape in the State. I think DOE sites do a good job with this.


What good are regulations if the employers aren't abiding and the regulators are not enforcing?  There is nothing more important to me in OSHA regulations than the responsibility of employers to characterize the respiratory hazards their employees face.  I want to highlight two shortcomings to the implementation and enforcement of these provisions:


1.  By regulatory verbiage and enforcement policy employers are not required to conduct Industrial Hygiene sampling or exposure assessments if OSHA can not find an overexposure.  In essence, if OSHA investigated a worksite or employer and the employer did not have exposure data, unless an OSHA compliance office sampled an employee or work task and found an exposure over the AL or PEL, OSHA would not compel the employer to conduct exposure assessments.**


2.  OSHA enforcement of health standards is weak and not a priority.


**there is not enough time to dissect this conundrum but in general if an employee was exposed to hazardous levels of chemicals, like silica, in the workplace an employee exposure record should be generated and accessible to that employee or former employee.  If an employer has no exposure records it should mean that the employee had no hazardous exposures but it could also mean the employer neglected to document them or even be aware of them.  This puts an ill person and the employer in a tough position if someone is trying to determine if a disease case is work-related.



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27 silica inspections over 4.5 years

VOSH response to an industry group

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"The compliance challenges are made even more difficult by the lack of guidance from

OSHA on how it intends to enforce and interpret the rule. To date, OSHA has not issued a

compliance directive educating compliance officers and employers on how it will enforce the

standard and, in particular Table 1." --Industry Group

Trace levels of enforcement + lack of employer exposure assessments = ?

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What I would consider an embarrassing statistic, a total of 20 construction inspections under the Silica NEP in Virginia over a 4.5 year period.

Subject matter resources

Construction workers exposure , IRSST (pdf)

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Rappaport AJIM 1984 (pdf)

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We know construction employees have hazardous exposures

But what about your sites?

Did you know the ACGIH TLV for respirable silica is the same as the OSHA action level?


Did you know that hidden in the OSHA 1926.1153 Preamble, OSHA declares that exposures above the action level but below the PEL likely indicate that employees are sometimes exposed above the PEL?


Did you know that OSHA intended the action level to motivate employers to reduce exposures to below the action level?


The intent was:

"OSHA’s preliminary risk assessment indicates that significant risk remains at the proposed PEL of 50 μg/m3. Where there is continuing significant risk, the decision in the Asbestos case (Bldg. and Constr.Trades Dep’t, AFL-CIO v. Brock, 838 F.2d 1258, 1274 (D.C. Cir. 1988)) indicated that OSHA should use its legal authority to impose additional requirements on employers to further reduce risk when those requirements will result in a greater than de minimis incremental benefit to workers’ health. OSHA’s preliminary conclusion is that the requirements triggered by the action level will result in a very real and necessary, but non-quantifiable, further reduction in risk beyond that provided by the PEL alone. OSHA’s choice of proposing an action level for exposure monitoring of one-half of the PEL is based on the Agency’s successful experience with other standards, including those for inorganic arsenic (29 CFR 1910.1018), ethylene oxide (29 CFR 1910.1047), benzene (29 CFR 1910.1028), and methylene chloride (29 CFR 1910.1052)."




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Big Silica

This brings us to the value of Big Silica Data

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TBD

Additional Information

Coming soon

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Prophetic Words

See the full article above in the SUBJECT MATTER RESOURCES section

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"The Rules of the Game: An Analysis of OSHA's Enforcement Strategy", Stephen M. Rappaport,PhD, American Journal of Industrial Medicine 6:291-303 (1984)

Remember no citations from OSHA does not guarantee the prevention of disease

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The article advocates that OSHA stop following a one sample over the PEL, absolute compliance strategy. 'OSHA interprets a PEL as a level never to be exceeded under any circumstances"

The NIOSH 0600/7500 myth

The 'Gold Standard' is kinda dull

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My own experience with NIOSH 0600/7500 sampling is that the dynamics of the environment, movement of people and equipment, orientation of people and equipment, dimensions of the space, location of the sampler, characteristics of the aerosol source and many other factors mean reported concentration values even in close vicinity to each other can be dramatically different.

Silica percentages are also a key variable

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When employer use the 'gold standard' as required by 1926.1153 we still must consider that the results can be of limited value and represent only one data point.  Not to mention that differences in percentage of quartz can mean significant differences in results.  The above Figure is taken from "Promoting early exposure monitoring for respirable crystalline silica:Taking the laboratory to the mine site", Cauda,Miller & Drake, JOEH 13:3, D39-D45