change efficacy from directly inputted parameter to inferred from changes in ACH #136
Description
At the moment, efficacy is a pre-specified parameter that is assumed to be the same in all locations of a particular setting type, irrespective of features of that setting.
It's likely that efficacy will vary as a function of the baseline ventilation rate (measured in air changes per hour (ACH) of a setting). We have some sense of this, as variation in ACH between settings is used to derive their relative riskiness in the force of infection term. We should more explicitly include ACH considerations when it comes to efficacy.
Practically, what this looks like would be defining something like an "average" efficacy and then having variation in that efficacy be a function of ACH. Or we could get even more granular with our representation, and have each setting have some detailed ventilation-related and UVC-related characteristics that are combined together mathematically to derive efficacy.
See here for sketch of approximately what we could do: eac6624