662 HAZWOPER for General Site Workers III

Protection Strategies

In construction, workers may be exposed to both ionizing and non-ionizing radiation from various sources, such as X-ray machines used in inspections, radioactive materials in certain industrial processes, and ultraviolet (UV) radiation from welding operations. To minimize excessive exposure, three key strategies—time, distance, and shielding—are essential for protecting worker health and safety.

Time

The longer a worker spends near a radiation source, the greater their exposure. To reduce risks, construction crews should limit the time they spend in high-radiation areas whenever possible.

• Example: During concrete inspection using X-ray imaging, workers should leave the area while the radiation is active and only return once the process is complete.
• Example: Welders should take breaks and rotate tasks to minimize prolonged exposure to intense UV radiation from welding arcs.

Distance

Radiation exposure decreases as the distance from the source increases. This principle is crucial for construction sites where radiation-emitting equipment is used.

• Example: When working near industrial radiography equipment, workers should maintain as much distance as possible from the radiation source.
• Example: Site supervisors should establish restricted zones with barriers to keep unnecessary personnel at a safe distance from active radiation sources.

Shielding

Shielding involves placing protective materials between workers and the radiation source to reduce exposure. Different types of shielding are required depending on the type of radiation present.

• Example: In construction projects involving radiographic testing of welds, lead barriers or concrete walls can be used to shield workers from ionizing radiation.
• Example: Welders should wear specialized PPE, such as welding helmets with proper lens shading, gloves, and flame-resistant clothing, to protect against non-ionizing UV radiation.

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