CEMENT CUTTING HAND OR PORTABLE HAZARDS:
Remember: Cutting concrete exposes silica, it’s not just dust. Beyond chronic coughing and shortness of breath, long-term exposure to concrete dust heightens the risk of severe health issues, including Silicosis: It can lead to breathing problems, a severe lung condition called Progressive Massive Fibrosis (PMF), or lung cancer. It is estimated that 230 people develop lung cancer each year as a result of past exposure to silica dust at work. Cancer Counsel (Jan 10, 2024).
ISSUES:
- Advantages of large concrete cutting equipment vs. handheld equipment:
- Capable of making deep and long cuts
- Less operator fatigue
- Good for extensive cutting
- Disadvantages:
- Accident exposure greater and with greater consequences
- Usually requires greater coordination
- Control areas are often of significant size
- Greater exposure to other employees and the general public
- Greater exposure for contacting utilities
OSHA STANDARDS:
OSHA Standard Subpart Z 1926.1153 Scope and application. This section applies to all occupational exposures to respirable crystalline silica in construction work, except where employee exposure will remain below 25 micrograms per cubic meter of air (25 ug/m3) as an 8-hour time-weighted average (TWA) under any foreseeable conditions.
Other OSHA Standard Subpart 1926.856 Demolition:
- 1926.856(a) Mechanical equipment shall not be used on floors or working surfaces unless such floors or surfaces are of sufficient strength to support the imposed load.
- 1926.856(b) Floor openings shall have curbs or stop-logs to prevent equipment from running over the edge.
- 1926.859(g) During demolition, continuing inspections by a competent person shall be made as the work progresses to detect hazards resulting from weakened or deteriorated floors, or walls, or loosened material. No employee shall be permitted to work where such hazards exist until they are corrected by shoring, bracing, or other effective means.
- Employee exposure means the exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.
- A high-efficiency particulate air [HEPA] filter is a filter that is at least 99.97 percent efficient in removing mono-dispersed particles of 0.3 micrometers in diameter.
- Objective data means information, such as air monitoring data from industry-wide surveys.
- Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers specified in the International Organization for Standardization (ISO) 7708:1995: Air Quality—Particle Size Fraction Definitions for Health-Related Sampling.
OSHA Standard Subpart Z 1926.1153(c)(1) For each employee engaged in a task identified on Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task on Table 1, unless the employer assesses and limits the exposure of the employee to respirable crystalline silica in accordance with paragraph (d) of this section.
MACHINE HAZARDS:
- Walk-behind saws.
- Walk-behind milling machines and floor grinders.
- Drivable saws
- Rig-mounted core saws or drills
- Small drivable milling machines
- Large drivable milling machines
- Crushing machines.
- Dowel drilling rigs for concrete
- Vehicle-mounted drilling rigs for rock and concrete
- Heavy equipment and utility vehicles used to abrade or fracture silica-containing materials
- Heavy equipment and utility vehicles for tasks such as grading and excavating
FOCUS POINTS YOU NEED TO KNOW:
- Table 1 – Subpart Z 1926.1153(c)(1) provides requirements for 18 pretested tasks performed in construction. If the task being performed is not on Table 1 – Objective data or annual task-specific testing is required.
- Cutting through hidden utilities (electric, gas, water lines).
- GFCI protection is required with all equipment.
- Machine guarding is required and all this equipment.
- Struck by or caught between issues are significant with larger equipment.
- Other chemical exposures created by operations i.e. (asbestos or lead, etc.).
- If the task being performed is not on Table 1 – Objective data or annual task-specific testing is required.
- Testing must be completed for every type of produce, i.e. (precast, CMU, poured concrete. etc.).
- When using respirators all the requirements for a written respirator plan is additionally required.
- Training is essential so that all employees understand the task and why proper utilization of equipment and PPE is 100% compliant. Special Hazards Cutting Concrete With Gas or Heavy Equipment:
- Cutting concrete exposes silica. Silica is not just dust. A piece of rebar or some other material, can kick back and flip the saw up.
- Know the torque settings needed for the material and type of drilling.
- The obvious potential for injuries is having part of a worker’s body come into contact with a moving saw blade or core drill.
- Structural considerations (reverse engineering required).
- Working in safety zones or in public areas. Traffic and pedestrian control.
- Push-Back, Kick-back, or Pull-in – These are potentially fatal forces, experienced suddenly, and often difficult to manage.
- Toxic Fumes – In the lack of proper ventilation, gas motor emissions packaged with carbon monoxide and other harmful gases can generate fumes to hazardous levels.
- Noise – A high decibel of noise that emerges from concrete cutting or drilling is a potential workplace hazard.
- Vibration – Whole body or arm vibration, if borne for a long time by using a drilling and cutting device, may result in nerve, joint, and circulatory damage.
- Adequate water supplies are especially important during larger cuts and operations.
- Uneven Surfaces – Such a situation can enhance the risk of tripping and stumbling of the operator, leading to an unusual movement of the saw resulting in kick-back.
