As Black Lives Matter protests continue across the U.S., police have deployed various “less lethal” weapons to disperse participants. Tear gas, rubber bullets, flash bang grenades and long-range acoustic devices (LRADs) are designed to control crowds. But they are sometimes used in situations where people have nowhere to run. So some protesters have been gearing up to protect themselves from such weapons and suspected surveillance technology—not to mention the novel coronavirus.
There are a lot of guides circulating online that provide suggestions on preventing harm and treating injuries. They often contain conflicting information, however. Here is what some existing medical research has to say about how to stay safe, one body part at a time.
[More information on the history of less lethal weapons—and what they do to the human body.]
During a protest, eyes are vulnerable to chemical irritants, rubber bullets, flash bang grenades—and even coronavirus infection. The best way to guard against most of these threats is to wear shatterproof goggles. They can block direct contact with tear gas and pepper spray (which are often the first weapons used against crowds), as well as viruses. Contact lenses should be avoided: they may prolong the amount of time a contaminant stays pressed against the eye. Because many people do not have a pair of ski, swimming, or construction goggles at home, however, protesters say they have been relying on home remedies after exposure.
“There are a lot of different things that are considered home remedies for pepper spray,” says Stephanie H. Shih, a ceramic artist who has been attending protests in New York City. She says there is much confusion about this topic on the street: Some people pour water in their eyes. Others use milk, a mixture of baking soda and water or a watered-down preparation of an over-the-counter heartburn treatment with aluminum and magnesium hydroxide as its main active ingredients. Yet none of those three methods are recommended from a medical standpoint. “Copious amounts of water and soap and fresh air are really the only things that make a significant difference,” says emergency physician Rohini J. Haar, a medical expert at Physicians for Human Rights and a research fellow at the Human Rights Center at the University of California, Berkeley, School of Law. She says various geographical regions seem to have their own remedies. But no medical studies have tested most of these solutions.
Eyes are additionally vulnerable to the intense bursts of light emitted by flash bangs, also called stun grenades, during protests. Typical sunglasses do not help much. Wearing shatterproof goggles, however, could protect people’s eyes from the plastic fragments that are sometimes hurled when flash bangs explode. Goggles can also slightly shield the optic organs against rubber bullets—but not entirely. The American Academy of Ophthalmology warns that such eye coverings are not a foolproof measure.
Incredibly loud sounds are sometimes deployed to quell protests. For example, when stun grenades go off, a loud “bang” accompanies the intense light. The volume can be 160 to 180 decibels—exceeding the noise level at rock concerts or near jet engines. And it can cause temporary hearing loss and disorientation.
The acoustic weapons called LRADs focus sound waves in one direction and over long distances. Although they are not as widely used as tear gas or pepper spray, police unleashed one in Portland, Ore., this month and at previous Black Lives Matter protests. The devices can cause permanent damage: according to the American Speech-Language-Hearing Association, an LRAD “is capable of causing not only permanent hearing loss, but also migraine, vestibular, and other auditory symptoms.”
Few medical studies have been conducted on acoustic weapons’ effects on humans or on how to protect against them. A Physicians for Human Rights (PHR) report says the “use of earplugs or firmly blocking the ears with hands can decrease the sound by [20 to 30 decibels], but this may not be enough to avoid significant injury.” Like earplugs, construction-grade earmuffs could reduce noise levels. They are bulky, however, which might not be practical during a protest.
Some activists worry police will turn to facial-recognition technology to track down protesters. Although the possibility has not been confirmed during this round of unrest, “the problem is that the use of facial recognition in many places and by many police departments is incredibly opaque,” says Amos Toh, a senior researcher on artificial intelligence and human rights at Human Rights Watch. “So even if they were using it, there is a quite significant chance that we won’t be apprised of [that fact].”
Either painting one’s face or wearing a mask can reduce the accuracy of facial recognition. And some kinds of masks are also key to protecting against the novel coronavirus.These approaches might not discourage authorities from using the technology, however, which potentially opens up other problems. “There is still a broader concern that the police will still continue to run facial recognition software, despite the higher risk of inaccuracy—leading to investigations of people who simply weren’t at a protest or were not the people they were looking for,” Toh warns. “I think there is a broader climate of abuse and overreach that needs to be addressed.”
Though active ingredients differ between specific types of tear gas and pepper spray, they all cause pain and inflammation in the eyes, respiratory system and skin. “Tear gas gives you the sensation of your skin and your throat and your nose—everything—sort of burning and itchy simultaneously,” says Omar Gowayed, co-chair of March for Science New York City and a Ph.D. candidate at the New York University Tandon School of Engineering. He has experienced the weapon firsthand. “It really does alter one’s perception of what’s going on before and after you’re exposed to it,” Gowayed says.
Anecdotal evidence suggests that wearing lotion or sunscreen can worsen the effects of tear gas and pepper spray, and some scientists back up this claim. No medical studies have tested the idea, though. And physicians generally recommend wearing sunscreen when outside during daylight hours.
For skin protection during protests, Haar recommends wearing body-covering clothing such as long-sleeve shirts and full-length pants. (Doing so can also cover up tattoos, which may be used by tattoo-recognition software to identify protesters.) If skin is exposed, washing afterward is key. “Decontamination is important when you get home,” Haar says. She advises that the best solution for mitigating exposure to chemical irritants—and to the coronavirus—involves wiping shoes and glasses, washing clothes and masks, and showering.
A systematic review of medical literature in PHR’s report shows that injuries to the lungs, heart and chest are the third most prevalent type of harm caused by tear gas and pepper spray, after damage to the eyes and skin. Recommendations floating around on the Internet suggest that soaking masks in either water or vinegar can help one breathe better. Unfortunately, “from a medical perspective, people really shouldn’t,” Haar says. “It’s really hard to breathe through a wet mask. And if you use vinegar, you can get light-headed from the fumes.” She stresses that simply wearing a clean mask can reduce chemical irritants’ effects on the respiratory system. Gas masks do an even better job of blocking tear gas and pepper spray, but they are not widely available and will not prevent wearers from potentially spreading the coronavirus.
Carrying a smartphone in one’s pocket makes it possible to connect with people and record police behavior. It also allows one to be tracked. Toh says there are two scenarios in which a U.S. police force can access location data from a phone. One is when police issue warrants to pull people’s location information from GPS-tracking apps such as Google Maps. Another is when they collect data from a so-called cell-site simulator, known as a stingray, which mimics a cell phone tower to collect such data.
Police use of location information has not been reported in the latest U.S. protests. It could be happening, however. To prevent such data from being monitored, some people have been setting their phones to airplane mode during protests. But “switching on airplane mode doesn’t necessarily mean that your Bluetooth and your Wi-Fi connections are disabled,” Toh notes. To fully protect data on one’s position, he recommends turning off both connections, as well as location services for individual apps.
Beyond location, biometric phone-unlocking tools—such as fingerprint recognition or Face ID—could be used to force people to provide access to their phones. “The U.S. government has historically tried to compel people to open their cell phones or to turn on their cell phones for government access, particularly at the border,” Toh says. Although the practice has also not been reported in the current round of protests, he says, “that troubling history does indicate the possibility that this might happen again.”
Although these recommendations could help protesters faced with less lethal weapons and advanced police surveillance tactics, many experts note that the onus should not be on individuals—especially when it comes to things such as rubber bullets. “There’s not a way to protect yourself from [them] except by not showing up at the protest. And that is exactly why they’re used,” Haar says. “What it really does is repress your basic rights to speech and assembly.”
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