People in NSW are living under Australia's toughest coronavirus lockdown and face fines of up to $11,000 if they break the rules.

The State Government has warned the new laws, which came into effect at midnight on Monday, could be in place for weeks.

It has issued guidelines clarifying when it's OK to leave the house.

Here's what you can leave your home for:

Work, if a person can't work from home

Work, if a person can't work from home School or an educational institution

School or an educational institution Shops for food and other essential items

Shops for food and other essential items Get medical care

Get medical care Exercise, but only if the exercise is done alone or with one other person

NSW Police Commissioner Mick Fuller said 13 tickets had been issued so far for infringements of the new laws.

"The reality is the messaging that the Premier and Chief Health Officer have been giving over the last weeks and months has not been getting through to some people," he said.

Beyond those essential reasons for leaving the home, the Government has provided a list which would "excuse" somebody being outside.

It includes:

Fleeing an unsafe home, so to avoid injury or illness

Fleeing an unsafe home, so to avoid injury or illness Dealing with an emergency or on compassionate grounds

Dealing with an emergency or on compassionate grounds Providing care or helping a vulnerable relative/person

Providing care or helping a vulnerable relative/person Taking your child to childcare

Taking your child to childcare Attending a wedding (adhering to the five-person limit) or a funeral (adhering to a 10-person limit)

Attending a wedding (adhering to the five-person limit) or a funeral (adhering to a 10-person limit) Moving house or moving between two places of residence

Moving house or moving between two places of residence Donating blood

Donating blood Fulfilling legal obligations

Fulfilling legal obligations Accessing support services such as employment services, mental services etc

Accessing support services such as employment services, mental services etc Fulfilling parental sharing arrangements of children (the Government says those conditions shouldn't change and children can move between homes)

Fulfilling parental sharing arrangements of children (the Government says those conditions shouldn't change and children can move between homes) Going to a place of worship or to provide pastoral care, if you are a priest, minister or member of a religious order.

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The police have the power to deliver on-the-spot fines of $1,000 to individuals who breach those rules.

The maximum penalty that can be given by a court is $11,000 and six months in jail.

For anybody who is outside their house, they can only be with one other person unless they're part of your immediate family or are housemates.

The same rule applies for having another person over to your house.

If you are inside, there can only be two people gathered in that room, and social distancing must be adhered to.