Welders wear special glass goggles or facemask with glass window to protect their eyes from

Options

A. Gamma rays
B. X-ray
C. Infrared
D. UV-radiations

Answer

To solve the question regarding why welders wear special glass goggles or facemasks, we need to analyze the types of radiation they are exposed to during welding and identify which one poses the greatest risk to their eyes.

### Step-by-Step Solution:

1. **Identify the Types of Radiation**: The question provides four options: gamma rays, x-rays, infrared radiation, and ultraviolet (UV) radiation. We need to understand the nature of each type of radiation.

2. **Understand the Nature of Welding**: Welding involves high temperatures and electric sparks, which can emit various types of electromagnetic radiation. Among these, UV radiation is particularly significant.

3. **Examine the Effects of UV Radiation**: UV radiation is known to be harmful to the eyes. It can cause conditions such as photokeratitis (sunburn of the cornea) and cataracts over prolonged exposure.

4. **Frequency Ranges of Radiation**:
- **Ultraviolet (UV) Radiation**: Frequency range is approximately \(10^{15} \text{ Hz} - 10^{17} \text{ Hz}\).
- **Infrared Radiation**: Frequency range is approximately \(3 \times 10^{11} \text{ Hz} - 4 \times 10^{14} \text{ Hz}\).
- **X-rays**: Frequency range is approximately \(3 \times 10^{16} \text{ Hz} - 3 \times 10^{19} \text{ Hz}\).
- **Gamma Rays**: Frequency range is approximately \(7.5 \times 10^{14} \text{ Hz} - 3 \times 10^{16} \text{ Hz}\).

5. **Determine the Correct Answer**: Based on the frequency ranges and the harmful effects of each type of radiation, we conclude that the UV radiation is the most relevant concern for welders. Therefore, the correct answer is option 4: UV radiation.

### Final Answer:
Welders wear special glass goggles or facemasks to protect their eyes from **UV radiation**.

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