Which pollutant can be continuously monitored?

The ability to continuously monitor a pollutant depends on the nature of the pollutant and the technologies available for detection. In this context, flammability can be continuously monitored using various sensors that detect the presence of flammable gases or vapors in the air. These sensors can provide real-time data to indicate changes in flammable conditions, making them essential for safety in environments where such risks are present.

In contrast, while chlorine, ammonia, and lead can also be measured, the technology or methods for continuous monitoring may not be as straightforward or feasible compared to flammability. For instance, chlorine and ammonia are typically monitored using specific monitors that may not provide continuous readings under all circumstances, and lead often requires different sampling techniques that may not lend themselves to continuous monitoring due to its particulate nature.

Thus, flammability stands out as the pollutant that can be effectively and continuously monitored, allowing for better safety and compliance in environments where it may pose a risk.