CONTROL OF SILICA DUST IN CONSTRUCTION 

Handheld Power Saws

Using a handheld power saw (also called a cut-off saw) to cut masonry, concrete, 

stone, or other silica-containing materials can generate respirable crystalline 

silica dust. When inhaled, the small particles of silica can irreversibly damage the 

lungs. This fact sheet describes dust controls that can be used to minimize the 

amount of dust that gets into the air when using handheld power saws with an 

integrated water delivery system as listed in Table 1 of the Respirable Crystalline 

Silica Standard for Construction, 29 CFR 1926.1153. This fact sheet does not apply 

to handheld saws used to cut fiber-cement board.

Engineering Control Method: Water applied continuously to the saw blade

Wet Cutting

Many handheld power saws come equipped with 

an integrated water delivery system designed 

to cool the blade by directing a continuous 

stream of water onto the blade where it wets 

the material being cut and reduces the amount 

of dust generated when cutting. Water can be 

supplied to the saw by either a pressurized 

container or by a constant water supply such as 

a hose connected to a faucet or construction site 

water supply. Water flow rates must be sufficient 

to minimize release of visible dust.

Photo courtesy of OSHA

A construction worker using a handheld power 

saw with an integrated water delivery system. 

The saw must be operated and maintained in 

accordance with manufacturer’s instructions 

to minimize dust emissions. Focus on the 

following areas:

• Check 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 before use to be sure 

it is in good condition and does not show 

excessive wear.

• Maintain and operating the saw’s dust-control 

equipment based on the manufacturer’s 

instructions.

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.

Wet Cutting Indoors or in Enclosed Areas

Wet cutting indoors or in enclosed areas may 

not reliably keep silica exposures low, so extra 

ventilation or a means of exhaust 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

FactSheet
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 the workers’ breathing zones.

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.

Respiratory Protection

In addition to using wet cutting methods, 

respiratory protection with a minimum 

Assigned Protection Factor (APF) of 10 is 

required on Table 1 when wet cutting with 

handheld masonry saws indoors or in an 

enclosed area, or used outdoors for more than 

four hours per shift.

When respirators are required, employers must 

put in place a written 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-3627 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.