With OSHA’s recent silica dust rule significantly reducing the permissible exposure limit (PEL) for silica dust, some groups have been working to quantify the levels at which workers are currently exposed. In Washington State, one worker — an abrasive blaster — had their exposure measured at 130 times the PEL! The results of another recently published study, this time of construction workers in Massachusetts, aren’t quite so drastic, but they still show very high levels of silica exposure are common. The researchers assessed exposure to respirable crystalline silica and respirable dust during demolition, crushing, and chipping. They took 51 personal breathing zone samples from several types of employees:
- Operating engineers working at demolition and crushing sites
- Laborers performing miscellaneous tasks at demolition sites
- Crushing machine tenders at crushing sites
- Chipping workers at substructure bridge repair sites
- For chipping workers, using respirators was not sufficient to bring exposure below the PEL.
- For crushing tenders, the use of a water spraying system was able to bring exposure below the PEL.
