How many different types of gas masks would the government have to provide?

The number of different types of gas masks a government would need to provide depends on various factors, including the specific threats faced (e.g., chemical, biological, radiological agents), the population Demographics, and the intended use (military, emergency responders, civilians). Typically, a range of masks for adults and children, along with specialized models for first responders and high-risk professions, would be necessary. Additionally, masks should accommodate various features such as filter types, fit, and comfort for extended wear. Overall, a comprehensive approach would likely involve several distinct models tailored to different needs.