Swedish Candelabras – Finis

It is considered good practice to finish up the old projects before embarking on new ones, but that doesn’t seem to be my way.  The new one gets started and the old one languishes in its nearly complete state, sometimes for years, until I grant amnesty, allowing it to fade into memory.

I had reached the point in the Swedish candelabra project where the challenges of woodworking had been solved, a working prototype had been made, a dozen pieces had been crafted, and all that was left were the trivial details of wiring the electric LED candles.

It turned out that, while not technically challenging, it was incredibly tedious, threading wires, stripping insulation, soldering the bulb contacts, splicing connections and gluing the simulated plastic candlesticks in place.  The first one I assembled took hours.

With eleven more to go, I found lots of excuses to not do them.  Eventually however, when the summer heat advisories provided reason to retreat to the cool workroom in my home, I would complete one, or maybe two, each day.  Eventually I reached the last one, by which time I was proficient– only an hour of assembly!

I can now declare this project complete, and I look forward to displaying the candelabras in our windows when the season shifts once again to long cold nights.  I hope they are seen by the passing neighbors as signs of hope, warmth, welcome, and good cheer, just like the ones we enjoyed in Sweden.

The ancestral home of my great-great-grandfather Sven Johan Lundberg in Mulseryd, Sweden, during a light snowfall last December. If you look closely you will find that each window hosts a welcoming candelabra.

The 15-minute rule, and other covid recommendations

Keeping an eye on my watch while conversing.

Since writing the previous blog entry (“What is my risk?”) I have encountered additional information to refine the risk calculation I outlined.  I found a reference that provides a better value for the relative intensity of aerosol generation between the activities of talking and passive breathing: approximately 10X (compared to my placeholder value of 2).  When this weighting is applied to the social interaction duration histogram, the critical exposure is reduced from four person-intensity-hours to three.  

This does not seem like a large impact on critical exposure but the intensity level associated with talking now requires that all of those short interactions become shorter.  If the critical exposure is 3 hours at level 1 (silent breathing in the same room), and talking is 10 times more intense, then an exposure of 0.3 hours (18 minutes) in conversation with an infectious person will deliver the critical dose of virus-laden aerosols.  This suggests a limit of 15 minutes in any interaction with a stranger: the 15-minute rule.

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What is my risk?

Taking a calculated risk at a favorite restaurant’s outdoor patio

Ever since the covid19 stay-at-home orders were relaxed for my state, I have been struggling to find some rules to guide me as we try to safely host small gatherings with qualified friends (today’s rules: outdoors, safe-distancing, maximum of two guests–who have also been in semi-quarantine).

I’d like to know “what is my risk?” after encountering N people in a day and spending a certain amount of time with each.  In particular, if I interact with store clerks for a few minutes each, walk or bicycle past maybe a hundred people, or sit in a (sparse) movie theater with a few dozen others for two hours, what risks am I taking?  I want to put it in relative terms with the risk I willingly accept when I drive a few miles for an everyday errand.

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