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Answering Your Questions on the New Silica Standard

LHSFNA Management Co-Chairman Noel C. Borck
LHSFNA Management
Noel C. Borck

Before OSHA’s new silica rule even went into effect this June, the LHSFNA’s Occupational Safety & Health Division was already working with LIUNA signatory contractors who wanted to ensure they were protecting LIUNA members on their sites and complying with the new standard.

“Even though enforcement isn’t scheduled to begin until June of 2017, the Fund encourages all LIUNA signatory contractors to be proactive about educating themselves on the new standard,” says LHSFNA Management Co-Chairman Noel C. Borck. “For employers who already go above and beyond to protect workers from dangerous levels of silica, the work practices in the new standard will seem very familiar.”

Below are answers to some common questions we’ve received about the new standard. For a summary of what’s included in the new rule, check out our May article, “Getting to Know OSHA’s New Silica Standard” by going to and clicking on Lifelines Archives.

1. What is the permissible exposure limit in the new standard?

The permissible exposure limit (PEL) has been reduced from 250 micrograms per cubic meter (µg/m3) in construction to 50 µg/m3. The action level (AL), the exposure level at which employers have to begin mandatory actions, is 25 µg/m3. Like the old standard, both of these exposure levels are averaged over eight hours.

2. When are employees required to wear respirators?

Respirator use in the new standard depends on which compliance option employers choose to follow.

  • Table 1: Respirator requirements are listed by task, with different requirements for exposures more than or less than four hours.
  • Performance Option or Scheduled Sampling: Respirators are required when objective data or sampling shows that exposures will exceed the 50 µg/m3 PEL.

In all cases, the new standard mandates engineering controls as the primary method to control exposures.

3. In Table 1, when engineering controls and respirators are listed, are both required?

Yes, engineering controls must always be followed, and if a respirator is listed, it must be used. However, most tasks on Table 1 don’t require respirators because the listed engineering controls are enough to keep exposures below the PEL.

4. In the performance option, what is “objective data”?

“Objective data” is information (e.g., air monitoring data from industry-wide surveys, calculations based on the composition of a substance) that lists employee exposures from a specific material, process or task. The data must closely resemble conditions on your site for it to be used. This means it shouldn’t be from a day that’s not representative of normal site conditions or used just because the data shows particularly low exposures.

The Fund recommends that signatory contractors ask the OSH Division to review their objective data to help ensure it adequately reflects industry averages for the given task or process.

5. When does medical surveillance trigger in the new standard?

The new standard requires employers to offer medical exams at no cost to employees if they will be expected to wear a respirator for 30 or more days per year due to silica exposure. Once taken, the exam is good for three years.

Have more questions about the standard? Then sign up for the Fund’s next webinar, “Complying with OSHA’s New Silica Standard: What You Need to Know.” Available to all LIUNA signatory contractors and affiliates, the webinar will be held on August 10th and August 11th from 2-3 p.m. (EDT).

Still have questions? Visit our Silica web page or call the Fund’s OSH Division at 202-628-5465. The Fund also offers several publications on this topic, including the Silica Health Alert and Controlling Silica Exposure in Construction pamphlet. Order these publications and others at

[Nick Fox]

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