CONTROL OF SILICA DUST IN CONSTRUCTION 

Handheld Power Saws Used to Cut 

Fiber‐Cement Board 

Using a handheld circular saw to cut fiber-cement board can generate respirable 

crystalline silica dust. When inhaled over time, the small particles of silica can 

irreversibly damage the lungs. This fact sheet describes dust controls to minimize 

the amount of airborne dust when using handheld circular saws with a blade 

diameter of 8 inches or less to cut fiber-cement board as listed in Table 1 of the 

Respirable Crystalline Silica Standard for Construction, 29 CFR 1926.1153.

Engineering Control Method: Vacuum Dust Collection System

Fiber-cement board is a composite material made 

from cement, sand, and cellulose fibers. Cutting 

fiber-cement boards with high speed circular saws 

generates airborne dust that contains respirable 

crystalline silica. Specialty saw blades having 

4–8 teeth reduce the amount of respirable dust 

compared to standard masonry blades. Blades with 

polycrystalline diamond tips are recommended for 

longer cutting life.

Vacuum Dust Collection System (VDCS)

A commercially-available VDCS can be used to 

control dust when cutting fiber-cement board 

outdoors with a handheld power saw equipped 

with a blade of 8 inches or less.

The VDCS includes:

• A handheld circular saw with a partially enclosed 

saw blade equipped with either an integrated 

dust collection port, or a commercially available 

adapter installed per manufacturer’s directions. 

• A fiber-cement saw blade less than 8 inches 

in diameter. 

• A vacuum that is recommended by the tool 

manufacturer with enough air flow to capture 

dust at the cutting point. Use a vacuum rated 

at 80 cubic feet per minute or higher for 

effective capture.

• Filter with a 99 percent or greater efficiency in 

the vacuum exhaust. HEPA filters may be used 

but are not required. For longer filter life, use 

of a disposable filter bag or cyclone pre-filter is 

recommended. 

• A vacuum exhaust hose capable of providing 

the airflow recommended by the tool 

manufacturer. A 1.25” to 2” diameter vacuum 

hose is typically adequate.

Photo courtesy of NIOSH

Worker cutting fiber-cement board outdoors using a handheld 

power saw with a vacuum dust collection system. The dust 

collection system consists of a saw with a partially enclosed 

blade, vacuum hose, and dust collector positioned between the 

saw horses. Note that while this system is effective at controlling 

dust, some dust is still visible. 

A VDCS is most effective when workers are 

properly trained and use good work practices. 

Focus on the following areas:

• Keep the vacuum hose clear and free of debris, 

kinks, and tight bends.

FactSheet
• Turn the vacuum off and on regularly to reduce 

dust buildup on the filter, if it is not self-cleaning. 

For best results, use a vacuum with an actuator 

switch that allows the vacuum to be powered on 

and off using the saw.

• Change vacuum-collection bags at least as often 

as the manufacturer recommends.

• Set up a regular schedule for maintenance.

• Avoid exposure to dust when changing vacuum 

bags and cleaning or replacing air filters.

Compressed Air. Unless there is a ventilation 

system that effectively captures the dust 

cloud, do not use compressed air or blowers 

to clean surfaces, clothing, or filters because it 

can increase exposure to silica. Instead, clean 

only with a HEPA filter-equipped vacuum or by 

wet methods.

Respiratory Protection

When properly used, a VDCS can effectively control 

silica dust. Therefore, Table 1 does not require use 

of respiratory protection when cutting fiber-cement 

board outdoors using a handheld power saw with 

a blade 8 inches or smaller in diameter. For indoor

use, or with blades larger than 8 inches, Table 1 

does not apply and the employers must conduct 

an exposure assessment and may need to take 

additional action, including the implementation of a 

respiratory protection program.

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-3927 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.