Take a walk around Brisbane city and you'll probably see a few people whizzing about on bright green, electric scooters.

They're part of a new scooter-sharing scheme — similar to bike-sharing — which has been brought to Australia by the Californian tech start-up, Lime.

What is scooter-sharing? Scooter-sharing is like bike-sharing, but instead of hiring bicycles you hire motorised foot scooters

Scooter-sharing is like bike-sharing, but instead of hiring bicycles you hire motorised foot scooters The scooters are designed for the last leg of your journey — from the train or bus to the office

The scooters are designed for the last leg of your journey — from the train or bus to the office They are generally fitted with rechargeable batteries that can be charged between uses

They are generally fitted with rechargeable batteries that can be charged between uses Users are charged a booking fee via an app and then pay for each minute they ride

Users are charged a booking fee via an app and then pay for each minute they ride There are multiple companies offering schemes in the US

There are multiple companies offering schemes in the US Some cities have had trouble with the scooters becoming a public nuisance

Lime wants to expand to other cities, including Sydney, Melbourne and Perth, and other competitors may be on the way.

But nailing down new laws for the "innovative devices" which are considered motor vehicles in some states is proving difficult.

In December, Queensland introduced new rules for "rideables" which clarify where you can ride e-scooters and how fast you can go.

But the National Transport Commission is still investigating how they can be safely used in Australia, and doesn't plan to release its discussion paper until March next year.

"The current regulatory framework does not provide for the use of new and innovative personal-use devices that are readily available for sale today," it says.

So let's take a look at the new rules that have been drawn up in Queensland, and what's happening in some other states.

Who can ride them?

In Queensland, you don't need a driver's licence to ride an e-scooter, but you do need to be at least 16 years old.

Children between the ages of 12 and 16 can also ride them, but only if they're accompanied by an adult.

Only one person is allowed on a rideable at a time. ( ABC News: Dan Nancarrow )

How fast are you allowed to go?

According to the Queensland Department of Transport and Main Roads, you can ride up to 25 kilometres per hour on an e-scooter, but you must be able to stop quickly to avoid a collision.

Lime scooters, as an example, are designed to travel up to 23kph.

Do you have to wear a helmet?

Yep. Just like when riding a bike, you will need to wear an approved helmet.

In Brisbane you can find some scooters with a helmet hanging on their handlebars. But other times you may have to bring your own.

Rideables in Queensland must also be fitted with working lights and reflectors if you're using them at night.

Where can you ride them?

In Queensland, e-scooters can only be ridden on paths.

You cannot ride them on the road, even in on-road bike lanes, unless you're crossing at a set of lights or avoiding an obstruction on the footpath.

On separated paths — where there is a lane for bicycles and a lane for pedestrians —you'll need to stick to the bicycle side.

What about alcohol and mobile phones?

These are big no-noes.

The rules in Queensland state you cannot use a mobile phone while on an e-scooter, or drink and ride.

If you get caught doing either, you'll be slapped with a minimum $130 fine.

You'll also need to find a safe space to park your e-scooter. ( ABC News: Dan Nancarrow )

Where do you park them?

This has been an issue in some cities overseas, with scooters ending up in rivers and oceans.

The Queensland Department of Transport and Main Roads says only that they must be parked in a "safe and responsible" way.

"Hire companies may have additional conditions of use in addition to these rules," it says.

What's the deal in other states?

In New South Wales, powered foot scooters are currently not permitted in public areas and can only be used on private land.

However, a spokesperson for Transport for NSW said a trial of e-scooters was "being explored".

In Victoria, Lime has conducted a few small trials, including one at Monash University.

But the state's road rules state that any motorised scooter that can go faster than 10kph is classed as a motor vehicle.

That means it needs to be registered, or used only on private property.