# FactSheet

# OSHA’s Crystalline Silica Rule: Construction

**OSHA is issuing two standards to protect workers from exposure to respirable**  
**crystalline silica—one for construction, and the other for general industry and**  
**maritime—in order to allow employers to tailor solutions to the specific conditions**  
**in their workplaces.**

## Who is affected by the construction standard?

About two million construction workers are  
exposed to respirable crystalline silica in over  
600,000 workplaces. OSHA estimates that more  
than 840,000 of these workers are exposed to  
silica levels that exceed the new permissible  
exposure limit (PEL).

Exposure to respirable crystalline silica can  
cause silicosis, lung cancer, other respiratory  
diseases, and kidney disease. Exposure can occur  
during common construction tasks such as using  
masonry saws, grinders, drills, jackhammers  
and handheld powered chipping tools; operating  
vehicle-mounted drilling rigs; milling; operating  
crushing machines; and using heavy equipment  
for demolition or certain other tasks.

!
*Without dust controls, using a handheld power saw to cut concrete*  
*can expose workers to high levels of respirable crystalline silica.*

The construction standard does not apply where  
exposures will remain low under any foreseeable  
conditions; for example, when only performing  
tasks such as mixing mortar; pouring concrete  
footers, slab foundation and foundation walls;  
and removing concrete formwork.

## What does the standard require?

The standard requires employers to limit worker  
exposures to respirable crystalline silica and to  
take other steps to protect workers.

The standard provides flexible alternatives,  
especially useful for small employers. Employers  
can either use a control method laid out in **Table 1**  
of the construction standard, or they can measure  
workers’ exposure to silica and independently  
decide which dust controls work best to limit  
exposures to the PEL in their workplaces.

Regardless of which exposure control method is  
used, all construction employers covered by the  
standard are required to:

• Establish and implement a **written exposure**  
**control plan** that identifies tasks that involve  
exposure and methods used to protect workers,  
including procedures to restrict access to work  
areas where high exposures may occur.

• Designate a **competent** person to implement  
the written exposure control plan.

• Restrict **housekeeping** practices that expose  
workers to silica where feasible alternatives  
are available.

• Offer **medical exams**—including chest X-rays  
and lung function tests—every three years for  
workers who are required by the standard to  
wear a respirator for 30 or more days per year.

---

• **Train workers** on work operations that result  
in silica exposure and ways to limit exposure.

• **Keep records** of workers’ silica exposure and  
medical exams.

## What is Table 1?

**Table 1** matches common construction tasks with  
dust control methods, so employers know exactly  
what they need to do to limit worker exposures  
to silica. The dust control measures listed in the  
table include methods known to be effective, like  
using water to keep dust from getting into the  
air or using ventilation to capture dust. In some  
operations, respirators may also be needed.

Employers who follow Table 1 correctly are not  
required to measure workers’ exposure to silica  
and are not subject to the PEL.

## Table 1 Example: Handheld Power Saws

If workers are sawing silica-containing materials,  
they can use a saw with a built-in system that  
applies water to the saw blade. The water limits  
the amount of respirable crystalline silica that  
gets into the air.

**Table 1:  Specified Exposure Control Methods**  
**When Working with Materials Containing**  
**Crystalline Silica**

| Equipment/Task                         | Engineering and Work Practice Control Methods                                                                                                           | Required Respiratory Protection and Minimum Assigned Protection Factor(APF)  |  |
|----------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------|--|
| Equipment/Task                         | Engineering and Work Practice Control Methods                                                                                                           | ≤4hrs/shift                                                      | >4hrs/shift   |
| (ii)Handheld power saws(any blade diameter) | Use saw equipped with integrated water delivery system that continuously feeds water to the blade.Operate and maintain tool in accordance with manufacturer&#x27;s instructions to minimize dust emissions. •When used outdoors. •When used indoors or in an enclosed area. | NoneAPF10                                                       | APF10APF10     |

*Excerpt from Table 1.*

*See regulatory text for construction standard, with complete Table 1  
at www.osha.gov/silica/SilicaConstructionRegText.pdf.

In this example, if a worker uses the saw  
outdoors for four hours or less per day, no  
respirator would be needed. If a worker uses the  
saw for more than four hours per day or any time  
indoors, he or she would need to use a respirator  
with an assigned protection factor (APF) of at  
least 10. In this case, a NIOSH-certified filtering  
facepiece respirator that covers the nose and  
mouth (sometimes referred to as a dust mask)  
could be used. If a worker needs to use a  
respirator on 30 or more days a year, he or she  
would need to be offered a medical exam.

## Alternative exposure control methods

Employers who do not use control methods in  
Table 1 must:

• Measure the amount of silica that workers are  
exposed to if it may be at or above an **action**  
**level of 25 μg/m** (micrograms of silica per  
cubic meter of air), averaged over an eighthour day.

• Protect workers from respirable crystalline  
silica exposures above the **permissible**  
**exposure limit of 50 μg/m³**, averaged over an  
eight-hour day.

• Use **dust controls** to protect workers from  
silica exposures above the PEL.

• Provide **respirators** to workers when dust  
controls cannot limit exposures to the PEL.

## When are employers required to comply with the standard?

Construction employers must comply with all  
requirements of the standard by June 23, 2017,  
except requirements for laboratory evaluation of  
exposure samples, which begin on June 23, 2018.

Additional information on OSHA’s silica rule can  
be found at www.osha.gov/silica.

OSHA can provide extensive help through a variety  
of programs, including technical assistance about  
effective safety and health programs, workplace  
consultations, and training and education.

OSHA’s On-site Consultation Program offers free  
and confidential occupational safety and health  
services to small and medium-sized businesses in  
all states and several territories across the country,  
with priority given to high-hazard worksites.  
On-site consultation services are separate from  
enforcement and do not result in penalties or  
citations. Consultants from state agencies or  
universities work with employers to identify workplace hazards, provide advice on compliance  
with OSHA standards, and assist in establishing  
and improving safety and health management  
systems. To locate the OSHA On-site Consultation  
Program nearest you, call 1-800-321-OSHA (6742)  
or visit www.osha.gov/dcsp/smallbusiness.

For more information on this and other healthrelated issues impacting workers, to report an  
emergency, fatality, inpatient hospitalization, or to  
file a confidential complaint, contact your nearest  
OSHA office, visit www.osha.gov, or call OSHA at  
1-800-321-OSHA (6742), TTY 1-877-889-5627.

**This is one in a series of informational fact sheets highlighting OSHA programs, policies or**  
**standards. It does not impose any new compliance requirements. For a comprehensive list of**  
**compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal**  
**Regulations. This information will be made available to sensory-impaired individuals upon request.**  
**The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.**

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