Saturday's earthquake could prove to be the tipping point for some businesses already squeezed by the recession, a Christchurch business leader says.

Canterbury Chamber of Commerce chief executive Peter Townsend said Christchurch's central city was like a ghost town today as the CBD remained in lockdown forcing hundreds of workers to stay at home.

"The only noises I can hear are helicopters flying around and army trucks going up and down the street."

The financial impact on some businesses would be devastating, he said.

"Some of the smaller retailers still have wages to pay and rent to pay and we are anticipating some of those smaller guys simply won't have the financial muscle to see their way through it."

Townsend said a government rescue package could be the difference between "life and death" for those businesses.

Cabinet is meeting today to get an early overview of the damage caused by the earthquake and Townsend said he too would be talking to the Christchurch City Council and various officials to initiate the first stage of recovery.

"I will know much more after that. It may be an area where the government can provide some support through some sort of monetary assistance to small businesses, he said.

Insurance Council head Chris Ryan estimates about 10 per cent of people aren't insured in Christchurch and about one or two per cent of those have been hit hard by Saturday's quake.

Businesses tended to be a bit better insured because they were required to by their auditors or by their company structures, he said.

The biggest risk to the commercial sector was to those businesses who didn't have the extent of cover against business interruption that they thought the did, he said.

People with private insurance can claim up to $100,000 on buildings and $20,000 for contents from Earthquake Commission, after which their private insurance kicks in.

Businesses are only covered by their private insurer, Ryan said.

Ryan said the insurance industry was well-placed to cope with the impact of the disaster.

"I think the key thing will be being able to absorb the calls and the claims that are coming in," Ryan said.

"The insurance industry is rushing a lot of people into the region now. They're diverting call centres from outside the region to take the calls, they're putting assessors into the Canterbury region to start working on the ground there - a lot of insurance staff are going into the area."

Ryan said people whose homes were damaged by the quake should contact The Earthquake Commission, while those with damage to their businesses should contact their insurance company or broker.

Those who are insured should not worry if they did not have a copy of their policy, as their insurer would be able to assist.

While not necessary, providing photos or documentation could speed up the claims process.

However, Ryan asked people to be patient.

"Make your house secure but certainly don't start rebuilding it on a long-term basis until you've got the green light from your insurance company, because the key thing is that you rebuild your home to the building standard, not in a makeshift way that could potentially cause problems down the tracks."

Ryan said the insurance industry would be able to absorb the costs from the quake.

Insurance companies themselves took out cover against catastrophes through re-insurance so had almost unlimited amounts of capital available to them to pay out for earthquakes.

"Our companies are fully structured to be able to cope with the cost because we have the access to the international capital markets," Ryan said.

Tower Insurance expects that insurance claims arising from the Christchurch earthquake will cost the company $5 million before tax.

While the total of possible claims is not yet known, re-insurance arrangements will cap the losses at $3.5 million after tax.

The key issue would be getting in enough materials and tradespeople to repair the damage, Ryan said.

"The availability of bricks and timber and roofing materials and materials for roads - that will be a big challenge, and it is around the world when you get these large events," he said.

"I think over the longer term there will be real benefits for the Canterbury region, because with hundreds of millions of dollars being put into the region by the insurance sector, hopefully in the longer term people will see some benefits from a very dark period now."