Which of the following is a common ignition source that should be controlled in hazardous locations?

Electrical sparks are a well-known and significant ignition source that must be controlled in hazardous locations. In environments where flammable gases, vapors, or dust are present, even a small spark can ignite these substances, potentially leading to explosions or fires. This makes it essential to implement strict measures, such as using equipment designed for hazardous locations, ensuring proper grounding, and adhering to safety regulations to prevent electrical sparks from occurring.

Bright sunlight, while it can contribute to heating materials, is less likely to directly ignite flammable substances compared to the risk posed by electrical sparks. Safe practices encompass a range of strategies for mitigating hazards but do not themselves serve as ignition sources. Wet surfaces can pose slip hazards but are not typically considered ignition sources in the context of hazardous locations. Thus, the focus on controlling electrical sparks is crucial for ensuring safety in environments where combustibles may be present.