CONTROL OF SILICA DUST IN CONSTRUCTION 

Rig-Mounted Core Saws or Drills

The use of rig-mounted core saws or drills to cut holes in concrete, masonry, or 

other silica-containing materials can generate respirable crystalline silica dust. 

When inhaled over time, the small particles of silica can irreversibly damage the 

lungs. This fact sheet describes methods to minimize the amount of airborne dust 

when using core saws or drills as listed in Table 1 of the Respirable Crystalline 

Silica Standard for Construction, 29 CFR 1926.1153.

Engineering Control Method: Water applied to cutting surface

Wet Methods

Wet cutting is an effective way to reduce the 

amount of silica dust when using a rig-mounted 

core saw or drill. Many types of core saws and 

drills come equipped with an integrated water 

delivery system that directs a continuous stream 

onto the blade/drill bit where it wets the material 

being drilled and reduces the amount of dust 

generated. Water flow rates must be sufficient to 

minimize the release of visible dust.

The rig-mounted core saw or drill must be 

operated and maintained in accordance with 

manufacturer’s instructions to minimize dust 

emissions. Focus on the following areas:

• Check and make sure that hoses are securely

connected and are not cracked or broken.

• Adjust nozzles so that water goes to the blade 

and wets the cutting area.

• Inspect the saw blade/drill bit to be sure 

it is in good condition and does not show 

excessive wear.

Clean up any slurry produced to prevent the 

slurry from drying and releasing silica dust into 

the air. Wet slurry can be cleaned up using, for 

example, shovels or a wet vacuum equipped with 

a HEPA filter.

Indoors or in Enclosed Areas

Using wet methods indoors or in an enclosed 

area may not reliably keep exposure low, so 

extra ventilation may be needed to reduce visible 

airborne dust. Extra ventilation can be supplied 

by using:

• Exhaust trunks

• Portable exhaust fans

• Air ducts

• Other means of mechanical ventilation

Ensure air flow is not impeded by the 

movements of employees during work, or by 

the opening or closing of doors and windows. 

Position the ventilation to move contaminated air 

away from workers’ breathing zones.

Respiratory Protection

When properly used, wet methods can effectively 

control exposure to silica dust. Therefore, Table 1 

does not require use of respiratory protection 

when operating rig-mounted core saws and drills 

using wet methods.

Photo courtesy of Hilti

Example of a core saw with integrated 

water delivery system.

FactSheet
Electrical Safety. Where water is used 

to control dust, electrical safety is a 

particular concern. Use ground-fault 

circuit interrupters (GFCIs) and watertight, 

sealable electrical connectors for electric 

tools and equipment on construction sites.

Vacuum Dust Collection System (VDCS)

For situations in which wet methods are not 

feasible, some rig-mounted core saws or drills 

come equipped with a VDCS to capture the dust 

generated when sawing. When operated with a 

VDCS instead of wet methods, Table 1 does not 

apply and therefore the employer must conduct 

an exposure assessment and may need to take 

additional actions such as implementing a 

respiratory protection program.

When respirators are required, employers must 

put in place a respiratory protection program in 

accordance with OSHA’s Respiratory Protection 

Standard, 29 CFR 1910.134.

Additional Information

For more information, visit www.osha.gov/silica

and see the OSHA Fact Sheet on the Crystalline 

Silica Rule for Construction, and the Small Entity 

Compliance Guide for the Respirable Crystalline 

Silica Standard for Construction.

OSHA can provide compliance assistance 

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, 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. To locate the OSHA 

On-Site Consultation Program nearest you, 

visit www.osha.gov/consultation.

Workers’ Rights

Workers have the right to:

• Working conditions that do not pose a risk of 

serious harm.

• Receive information and training (in a 

language and vocabulary the worker 

understands) about workplace hazards, 

methods to prevent them, and the OSHA 

standards that apply to their workplace.

• Review records of work-related injuries and 

illnesses.

• File a complaint asking OSHA to inspect their 

workplace if they believe there is a serious 

hazard or that their employer is not following 

OSHA’s rules. OSHA will keep all identities 

confidential.

• Exercise their rights under the law without 

retaliation, including reporting an injury or 

raising health and safety concerns with their 

employer or OSHA. If a worker has been 

retaliated against for using their rights, they 

must file a complaint with OSHA as soon as 

possible, but no later than 30 days.

For additional information, see OSHA’s Workers 

page.

How to Contact OSHA

Under the Occupational Safety and Health Act 

of 1970, employers are responsible for providing 

safe and healthful workplaces for their employees. 

OSHA’s role is to ensure these conditions for 

America’s working men and women by setting 

and enforcing standards, and providing training, 

education and assistance. For more information, 

visit www.osha.gov or call OSHA at 1-800-321-

OSHA (6742), TTY 1-877-889-5627.

DSG FS-3929 12/2017

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.