Safe Social Distancing for Cyclists
04/30/2020

By now, everyone is aware that the primary ways that individuals can protect against and fight the spread of the COVID-19 pandemic is to social  distance at least six feet apart, wash hands regularly, and wipe down surfaces frequently with an anti-bacterial/anti-virus spray or cloth.

Furthermore, most states have standing stay at home orders with exceptions for food shopping and picking up pharmaceutical supplies.  One other exception is going outdoors for exercise, although the six-foot distancing is still mandated.  Cycling has, in most areas, grown as an easy and effective means to effective exercise.  Ride safely, however.  Most if not all cycling clubs, White Clay Bicycle Club included, have suspended group rides; but what about riding with a friend?

Researchers from the Belgian university KU Leuven and Dutch colleagues at TU Eindhoven have concluded that six feet is far from an adequate distance for true safety when cycling with another.  Professor Blocken was the lead researcher and he specializes in  urban physics, wind engineering, and sports aerodynamics.

The white paper they published concluded that the slipstream from merely breathing requires a 10 meter (33 foot) distance when riding casually and a 20 meter (66 foot) separation when riding strenuously.  The microscopic particles linger in the air and can make someone behind the cyclist ride through the cloud, inhaling the dangerous vapor.  Have you ever ridden behind someone who sweats profusely and felt their heavy droplets of perspiration hitting you?  Now imagine how long invisible micro-particles might linger in the air as you follow someone.

A small bit of good news is that when two cyclist ride side-by-side, the risk is lessened because the vapor from their breath trails behind them but beware if there is a cross wind.

Separate studies have addressed cycling with masks.  They have concluded that masks are not a guarantee of safety but are certainly helpful, particularly if both parties are wearing them.  Remember that most experts agree that masks do more to protect others rather than to protect the wearer.  They caution that the cyclist needs to be extremely careful as masks hinder full airflow and can put additional stress on the rider due to less oxygen being inhaled than normal.  The suggestion is that  periodic rest periods will lessen any negative effects.  Don’t just soldier through it, ride smart.

The detailed white paper discussed above can be found at:
http://www.urbanphysics.net/Social%20Distancing%20v20_White_Paper.pdf

Michael A. Katz
White Clay Bicycle Club
Safety and Education Committee Chairperson