"If you’re really worried and want to get a test because of that exposure I would say that it makes sense to wait a week," he said. "A negative test a few days after being exposed is not very useful."
Experts said that whether protesting is safe depends on the protest.
"If they are and are doing their best to keep a distance from others, it is safe enough that people should make their own choices," said UCSF chair Wachter. "I completely understand the motivation for protesting, and people should just do it as safely as they can."
Have a Plan, and a Backup Plan
There's also a lot you can do before a protest.
Travel With Friends
Choose a meeting place beforehand in the event you get separated. You may also want to designate someone you can check in with who is not at the protest.
Charging your phone is an obvious one. But some activist groups also recommend taking digital security measures, such as disabling the fingerprint unlock feature to prevent a police officer from forcing you to unlock the phone. Others also recommend turning off text preview on messages and using a more secure messaging app, such as Signal.
Also, make sure that you can function without a phone. Consider writing down important phone numbers and keeping them with you.
Pack a Small Bag
Only bring essentials such as water, snacks, hand sanitizer and an extra phone charger.
The active component in tear gas adheres to moisture on your face. So it’s also good idea to pack an extra mask or face covering in case you are exposed to tear gas.
Some people recommend bringing basic medical supplies and a bandana soaked in vinegar or water in a sealed plastic bag in case there is tear gas. Others recommend a small bottle of water — or even better, a squirt bottle — to pour on your face and eyes.
Research the Intended Protest Route
This may be confusing since there's not always a clearly stated route (a protest is, or course, not a parade), but some have pre-planned routes.
By knowing where the protest is headed, you will be able to plan how you might avoid being caught in a kettle or other containment — and leave when you are ready.
Know Who Is Organizing the Protest
It's worth doing some research on the people and groups behind any protest you plan to attend, to make it's in alignment with your values and objectives. During Black Lives Matter protests in San Diego in June, for instance, organizers warned demonstrators to avoid specific events that they said had likely been surreptitiously coordinated by white nationalist groups.
Know Your Rights
You are entitled to free speech and freedom of assembly. However, it can be unclear during curfews and shelter-in-place orders. "Know your rights" guides for protests can be found here. Notably, when police issue an order to disperse it is meant to be the last resort for law enforcement.
“If officers issue a dispersal order, they must provide a reasonable opportunity to comply, including sufficient time and a clear, unobstructed exit path,” according to the American Civil Liberties Union.
If you are photographing others, it is recommended to respect privacy, as some may not want to have videos or photos taken. This may also depend on context, location and time of day. In some cases journalists, or those documenting events, have been the target of tear gas and rubber bullets.