Silica Dust Exposure Control

Document Number: [SWP-NUMBER]

Revision Date: [DATE]

Next Review Date: [NEXT REVIEW DATE]

Department: [DEPARTMENT NAME]

1. Scope

This safe work procedure (SWP) outlines the measures to control exposure to respirable crystalline silica dust during construction activities. It applies to all tasks where materials containing silica are disturbed, such as cutting, grinding, drilling, and abrasive blasting. The goal is to minimize worker exposure and maintain compliance with occupational health and safety regulations.

2. Definitions

Silica Dust Dust of respirable particle size and composed substantially of uncombined silica (Silicon Dioxide Si O₂ ). [3]

Silica Process A process that could release uncombined silica in a crystalline form in concentrations likely to exceed the contamination limits. [5]

Sandblasting The process of projecting sand by means of compressed air or steam or by a wheel. [3]

3. Responsibilities

3.1 Supervisors

Ensure workers are trained and competent in the safe work procedures.
Provide and maintain all necessary control measures and PPE.
Monitor air quality and worker exposure levels.

3.2 Workers

Use all control measures as instructed, including engineering controls, work practices, and PPE.
Participate in training and medical surveillance programs as required.
Report any concerns about silica dust exposure to the supervisor.

4. Potential Hazards and Risks

Hazard	Risk	Control Measures
Cutting concrete or masonry	Inhalation of silica dust leading to silicosis or other respiratory illnesses.	Use wet cutting methods to suppress dust. Provide local exhaust ventilation. Use respiratory protection (minimum APF 10).
Grinding or polishing concrete or masonry	Inhalation of silica dust leading to silicosis or other respiratory illnesses.	Use tools equipped with dust collection systems. Ensure dust collectors have HEPA filters and are properly maintained. Provide respiratory protection (minimum APF 10).
Drilling concrete or masonry	Inhalation of silica dust leading to silicosis or other respiratory illnesses.	Use drills with integrated water delivery systems or dust collection shrouds. Use HEPA-filtered vacuum for cleaning holes. Provide respiratory protection (minimum APF 10).
Abrasive blasting	High levels of silica dust exposure leading to acute silicosis and other respiratory illnesses.	Isolate the blasting operation in a blasting enclosure. Use respiratory protection (blasters' helmets supplied with clean air). Ensure proper ventilation and dust extraction systems are in place.
Dry sweeping or using compressed air for cleaning	Re-suspension of silica dust into the air, increasing inhalation risk.	Use vacuum methods with HEPA filters for cleaning. Wet methods should be used where vacuuming is not practicable. Prohibit dry sweeping or compressed air for cleaning.
Failure of ventilation equipment or enclosures	Increased silica dust exposure due to malfunctioning or ineffective control measures.	Ensure proper maintenance and regular inspections of ventilation equipment and enclosures. Address any defects immediately.

5. Personal Protective Equipment (PPE)

Half-face or Full-face Respirator with P100/HEPA filters: Provides respiratory protection against silica dust. Ensure proper fit and seal. Minimum APF 10 or higher, depending on exposure levels.
Safety Glasses or Goggles: Protects eyes from dust and debris. Required when there is a risk of eye irritation or injury.
Protective Coveralls: Protects skin from contamination. Coveralls should be maintained and cleaned in a safe manner. [1]
Gloves: Protects hands from contamination and abrasion.
Hard Hat: Provides head protection in areas with overhead hazards.

6. Equipment and Tools

The following equipment and tools are required for tasks that may generate silica dust. Ensure all equipment is in good working order and inspected regularly.

Concrete Saw with Integrated Water Delivery System: Equip with appropriate blade for the material being cut and ensure a constant water supply to suppress dust.
Grinder with Dust Collection System: Ensure the dust collector provides adequate airflow and is equipped with a HEPA filter.
HEPA-Filtered Vacuum: Use a vacuum with a HEPA filter to capture dust effectively.
Drill with Dust Collection Shroud or Integrated Water System: Ensure the drill is compatible with the dust collection system or has an integrated water delivery system.

8. Safe Work Procedure Steps

1. Hazard Assessment: Assess the potential for silica exposure by reviewing task requirements and material safety data sheets (SDS).
2. Training and Competency: Ensure all workers involved are trained on the hazards of silica, control measures, and proper use of PPE. Training must be established in writing. [2]
3. Work Area Preparation: Ensure the work area is clearly marked with hazard signs to prevent unauthorized access. Delimit the work area to maintain a safe distance. [2]
4. Implement Engineering Controls: Use engineering controls such as wet cutting methods, local exhaust ventilation, and dust collection systems to minimize dust generation.
5. Use of Personal Protective Equipment (PPE): Ensure all workers wear the required PPE, including respirators, safety glasses, gloves, and coveralls. Workers should be fully instructed in the need for and proper use of equipment and clothing. [1]
6. Perform Task Safely: Perform the task according to established safe work practices, ensuring continuous operation of dust control measures.
7. Monitor Exposure Levels: Regularly monitor the work area for visible dust and assess the effectiveness of control measures. Air monitoring should be performed to comply with the requirements of this section.
8. Clean Up Procedures: Clean the work area using vacuum methods with HEPA filters or wet methods. It is prohibited to use work methods that may cause dust from materials presumed to contain or containing crystalline silica to become suspended in the air, such as dry sweeping or the use of compressed air. [2]
9. Decontamination: Before leaving the work area, remove work clothes and place them in a closed bag or clean them using a wet cloth or HEPA vacuum. [2]
10. Equipment Maintenance: Regularly inspect and maintain all control equipment, including ventilation systems, dust collectors, and PPE.

9. Precautions and Safety Measures

Provide training to workers on the health hazards of silica exposure, proper use of control measures, and PPE requirements. The employer must train and inform workers of the risks, prevention methods and safe working methods. [4]
Ensure that all places where silica dust may accumulate are regularly cleaned using vacuum methods wherever practicable. [1]
Where it is not reasonably practicable to prevent the entry into the air of silica dust nor practicable to isolate the worker from the air containing silica dust, and for all cleaning and maintenance work, the employer shall provide for the use of each worker who may be exposed to silica dust approved respiratory protective equipment and protective clothing. [1]
Implement a respiratory protection program that includes fit testing, medical evaluations, and proper respirator maintenance.
Provide adequate ventilation, especially in confined areas. Ensure all national/local regulations are observed.

10. Emergency Procedures

10.1 General Emergency Response

In the event of a dust exposure incident: 1. Immediately stop work and move to a dust-free area. 2. Report the incident to the supervisor. 3. Seek medical attention if experiencing respiratory distress or other symptoms.

10.2 Specific Emergency Scenarios

Eye irritation or injury from silica dust: 1. Evacuate the area immediately. 2. Seek medical attention. 3. Report the incident to the supervisor and safety department.
Severe respiratory distress: 1. Assist the affected worker to fresh air. 2. Provide oxygen if available and trained to do so. 3. Seek immediate medical attention.

10.3 Emergency Contact Information

In case of emergency, contact the supervisor immediately. For serious injuries, call emergency services.

11. Incident Reporting and Investigation

All incidents, including silica exposure incidents, must be reported to the supervisor immediately. A written report must be submitted within 24 hours.

A thorough investigation will be conducted to determine the root cause of the incident and implement corrective actions to prevent recurrence.

Approved by: [NAME AND POSITION]

Date: [APPROVAL DATE]