[BostonCard]

Here's the article about the Amoy Gardens spread of SARS.

https://www.nejm.org/doi/full/10.1056/NEJMoa032867

Residents of the floors at the middle and upper levels in building E were at a significantly higher risk than residents on lower floors; this finding is consistent with a rising plume of contaminated warm air in the air shaft generated from a middle-level apartment unit. The risks for the different units matched the virus concentrations predicted with the use of multizone modeling. The distribution of risk in buildings B, C, and D corresponded well with the three-dimensional spread of virus-laden aerosols predicted with the use of computational fluid-dynamics modeling.

The prevailing wind (red arrows) during the period of possible exposure was northeasterly, or roughly perpendicular to the exterior walls of apartment units Dc and Da in building E. The distance between buildings E and B is 60 m. The direction from which the wind blew shifted from nearly north to east and even southeast. The red dot in building E indicates the unit that the index patient visited. The directional indicator for the units at the lower right-hand corner indicates the direction each unit faced. In the directional code (Ab, Ad, Ba, Bc, Cb, Cd, Da, Dc) used to designate an apartment unit, uppercase letters denote front-facing windows and lowercase letters side-facing windows.

According to our computational fluid-dynamics modeling, the buoyant plume (blue) rose from the air shaft between two housing units in building E (yellow) and was carried by a northeasterly wind toward the middle-level floors in buildings C and D. The L-shape structure (Panels A and B) was a nearby construction site that blocked the wind flowing toward lower-level floors in buildings E, C, and D. The wake flow of the construction site created a region of negative air pressure in the space between buildings E, C, and D (Panel B) that caused the plume to bend downward, toward buildings C and D.

BC

[BostonCard]

Here's the article about the Amoy Gardens spread of SARS.

https://www.nejm.org/doi/full/10.1056/NEJMoa032867

Residents of the floors at the middle and upper levels in building E were at a significantly higher risk than residents on lower floors; this finding is consistent with a rising plume of contaminated warm air in the air shaft generated from a middle-level apartment unit. The risks for the different units matched the virus concentrations predicted with the use of multizone modeling. The distribution of risk in buildings B, C, and D corresponded well with the three-dimensional spread of virus-laden aerosols predicted with the use of computational fluid-dynamics modeling.

The prevailing wind (red arrows) during the period of possible exposure was northeasterly, or roughly perpendicular to the exterior walls of apartment units Dc and Da in building E. The distance between buildings E and B is 60 m. The direction from which the wind blew shifted from nearly north to east and even southeast. The red dot in building E indicates the unit that the index patient visited. The directional indicator for the units at the lower right-hand corner indicates the direction each unit faced. In the directional code (Ab, Ad, Ba, Bc, Cb, Cd, Da, Dc) used to designate an apartment unit, uppercase letters denote front-facing windows and lowercase letters side-facing windows.

According to our computational fluid-dynamics modeling, the buoyant plume (blue) rose from the air shaft between two housing units in building E (yellow) and was carried by a northeasterly wind toward the middle-level floors in buildings C and D. The L-shape structure (Panels A and B) was a nearby construction site that blocked the wind flowing toward lower-level floors in buildings E, C, and D. The wake flow of the construction site created a region of negative air pressure in the space between buildings E, C, and D (Panel B) that caused the plume to bend downward, toward buildings C and D.

BC