Under what conditions will the Quatro's alarm activate?

The Quatro is a multi-gas detector designed to monitor specific hazardous gases, including hydrogen sulfide (H2S). It plays a vital role in maintaining safety in environments where exposure to toxic gases can occur. The alarm activates specifically when the concentration of hydrogen sulfide exceeds predetermined safe limits, because H2S is a highly toxic gas that can be lethal at relatively low concentrations.

Monitoring for hydrogen sulfide is crucial for personnel safety, especially in certain industrial settings and confined spaces where the gas is commonly found. The activation of the alarm alerts users to take immediate action, such as evacuating the area or implementing appropriate safety measures to mitigate exposure risks.

In contrast, the other conditions mentioned relate to different environmental factors that can present hazards, but they are not the primary focus or purpose of the Quatro's alarm system. Thus, option C is the most relevant answer regarding the specific activation conditions of the Quatro alarm.