Activities Have Significant Impact on Indoor COVID Risk

Activities Have Significant Impact on Indoor COVID Risk

Key Points:

Key Points:

Recommendations for Industry

Activities Have Significant Impact on Indoor COVID Risk

  1. Our university will be holding an indoor graduation ceremony for which we expect about 3,500 graduates and guests. We are requiring masks, but would like to have everyone sing a short song at the end of the ceremony. Would that have any effect on COVID risk?
  2. TAG has been receiving a number of questions about COVID risks associated with the return to indoor activities, including return to work. While the response to the risks will differ based on the calculation of variables (see below), the impact of the activities that will be happening in the space was clearly illustrated when TAG assisted in the calculations.

       That is, can singing be allowed at the graduation ceremony? In assisting with the calculation of risk for the case in question, TAG found:

  • 16 minutes of singing = 11 hours of breathing for the 3500 people in attendance.

The significance of this for businesses is that indoor air spaces need to be considered as you develop return-to-work protocols. As discussed in a previous TAG newsletter, the number of people, length of time in a confined space, and activity being performed have more impact on potential transmission than simply sitting six feet apart.

No matter how far apart people may be in the area, the air will mix and droplets spread over time, and the more active the people in the room, the greater this will be. Thus, businesses need to consider the ventilation rate of a room or area, along with number of people, volume of the space, the activities that take place, whether masks are worn, and various other factors based on the specifics of the area. It can be quite complex, but TAG has been assisting business with such determinations throughout the pandemic. Give us a call if you need assistance with this – or other aspects to be considered in returning your people to work.


Risk Matrix

Overall things are looking better in the US – including Michigan which is still higher than other states, but no longer so significantly. No state is above the 10% positive rate, and only four states over a 1.0 transmission rate. However other parts of the world are not doing so well,  including Canada where high COVID numbers are persisting in several provinces and vaccine supplies dwindling in others, and Asia which is seeing increasing case numbers. This does not bode well the opening of international travel, and businesses should continue investigating COVID conditions before traveling outside the US.

Positive trends –

  • The Government Stringency Index is 36 this week. This is the same as last week, indicating a stabilizing in government stringencies. Five (5) states’ (Arizona, California, Colorado, New Mexico, and Oregon) businesses continue to be in mixed opening stages.
  • In Figure 1, this week, we compare the case rate/100K (Table 1) in the population to the percentage of a state’s population that has been fully vaccinated (Table 2). Table 3 compares the previous week’s percentage of states’ populations that have become fully vaccinated full dose (and the rate of change between the last week and this week).

Table 1.

Figure 1.

Table 2.

Table 3.

  • No states have a TPR ≥ 10% and a case rate ≥ 25/100K people indicating that testing may not be adequate to fully characterize the true severity of the outbreak in the state (Table 4).
  • Only Michigan has a TPR < 10% and a case rate≥ 25/100K people, indicating that adequate testing is likely finding most symptomatic cases of illnesses (Table 4).

Table 4.

In Case You Missed It

  • In Monday’s Recommendations for Industry, we discussed continuing your public health worker protections for the control of Hepatitis in the wake of the lingering outbreak. Read More Here.