One of the earliest pieces of advice I ever got from my mother is to never share hats with someone. My coworker Erica Lourd received similar motherly advice, forbidden from using a friend’s hairbrush. Why? Because this is how things like lice and bedbugs can spread. And now with startup ’s common-use electric mopeds (and common-use helmets) deployed across Brooklyn and Queens, there are some hygiene concerns.

Recently, the company deployed 1,000 electric mopeds onto the streets of Brooklyn and Manhattan. They are meant for public use: People can sign up with the Revel app and ride the scooters for fun or as an alternative to the subway or a car while paying by the minute. It’s a great idea! Then you stop and consider the provided helmets are also for public use.

It is both unsafe and dangerous to ride really anything without a helmet, so I applaud Revel for providing them. Because I know trendy New Yorkers wouldn’t wear bulky helmets if they weren’t provided, regardless of the law. Each moped comes with two United States Department of Transportation safety-certified helmets, a big one and a small one, that are stored in the cargo compartment when the moped isn’t in use.

These helmets are then cleaned “every two to three days,” Paul Suhey, Revel’s co-founder and COO, told recently.

I found this concerning. True, it’s not as bad as never cleaning the helmets, but every two to three days doesn’t seem quite often enough, either, especially since warmer weather is upon the city. People sweat when it’s warm out and they sweat right into that helmet. It definitely gets gross! It’s also unclear how many people would use the moped and helmet in between cleanings.

Now, Revel also provides something of a head sock for you, the rider, just like you’d find at, say, the go kart place where your friend spun you out on the last lap and then laughed in your face about it and I WILL NEVER FORGIVE YOU. But!

I witnessed a lot of users jumping on and off of Revel’s mopeds—and not a single one of them were spotted using the hair cap. They simply popped the cargo compartment open, removed the helmet and planted it on top of their heads without really checking the inside of it first. It made my soul scream.

With this all in mind, I contacted Revel and a company spokesperson responded that “several times a week,” a Revel employee changes out the two batteries in each moped and performs a maintenance and safety check. Once that’s done, they clean the helmets and replenish the disposable hair caps that Revel provides to riders within the helmet case, ensuring that there are at least seven. All of this takes around two minutes per moped.

I asked what exactly the process of cleaning the helmets entailed. “Revel field technicians spray the inside and outside of the helmet with a disinfectant specifically designed for this type of equipment,” responded the rep. “This process is [meant] to create a safe environment for riders and guard against the spread of germs and bugs.”

The Centers for Disease Control that clothing, hats and bedding worn and used by an infected person be machine-washed with hot water and dried using hot air. Lice and its eggs can be killed when exposed to temperatures of over 128.3 degrees Fahrenheit for five minutes. Things that can’t be laundered need to be dry-cleaned or sealed in a plastic bag for two weeks.

Of course, there’s no way for Revel to enforce people to use the hair caps, despite the company saying that it encourages users to do so. I took a walk through Brooklyn this past weekend, where countless Revel scooters were parked on curbsides. (Revel, to its credit, doesn’t appear to be as intrusive on the neighborhood as . People actually seem to be alright at parking the things.) Again, no head sock usage.

The New York City Department of Health and Mental Hygiene declined to answer a specific list of emailed questions pertaining to this topic, but did direct us to its . It states that lice may be spread through the sharing of “hats and other contaminated accessories.”

The Environmental Protection Agency discussed a similar situation in a . In it, a school nurse told that she suspected the children were passing head lice to each other by sharing the school’s common bicycle helmets.

A particularly disgusting bit of the blog notes:

To control lice in helmets, the National Pediculosis Association recommends vacuuming and wiping out the helmets between uses. They note that a louse can survive less than 24 hours away from a human host, but the nits (eggs) on a hair left in the helmet could survive up to 10 days. Detachable foam fitting pads and the nylon straps can also be washed.

Prevention, Anderson recommended, included the children not sharing combs, brushes, hats or clothingwith anyone infected and to vacuum frequently.

The states that while it is “uncommon” for head lice to spread by contact with clothing or personal items, “head lice feet are specially adapted for holding onto human hair.” That means that if there are leftover hairs from an infected person left in the helmet, then it’s theoretically possible for the lice to spread.

Also, bedbugs have been .

There are some key takeaways here:

If you’re using a Revel moped, maybe roll up with your own (DOT-approved!) helmet.

If you’re using a Revel moped and you’re not lugging a helmet around, consider at least and keeping it in a bag or a pocket. And clean that thing, too.

But really, if you’re using a Revel helmet, and you don’t use a head sock, you may be in for Some Real Shit, let me tell you.