Dr Evans Lagudah fled with a colleague at the Commonwealth Scientific and Industrial Research Organisation on Monday as hailstones obliterated the glass roof panels above them.

"It was scary," Dr Lagudah said.

"It was a situation where we were working in the glasshouse and everything was normal and within seconds there were hailstones dropping from everywhere.

"Once we moved into the (front) room one of the panels of glass just went, it was almost like an explosion, and then they just started all falling around us.

"At that point I would have beaten Usain Bolt because the adrenaline just got into me to get out."

The storm badly damaged more than 90 per cent of the 65 glasshouses at the campus and wiped out years of research.

The majority of the research was aimed at improving crop sustainability and scientists had been growing wheat, barley, legumes and cotton in the glasshouses.

Some of the projects had been under way for three years.

The damage bill is still being assessed but is expected to costs tens of millions of dollars, while restarting the research could be delayed more than 12 months.

A record number of calls for help were made to the ACT Emergency Services Agency after 2044 residents rang the hotline, more than triple the annual average of calls.

As of 5pm on Tuesday 580 assistance jobs had been completed with 1464 outstanding.

NSW State Emergency Services crews have been brought in to help.

Hundreds of buildings and cars were badly damaged as golf-ball sized hail stones pelted the capital in a 30-minute frenzy.

Wild weather has thrashed the east coast this week and insurers have received more than 29,000 claims - 56 per cent from the ACT, 34 per cent from Victoria and 10 per cent from NSW.

Losses are estimated at $320 million. About two-thirds of claims are for damage to motor vehicles.

The Insurance Council of Australia has declared the storm a catastrophe, meaning thousands of claims will be processed quickly.

ICA spokesperson Campbell Fuller said nearly 11,000 claims had so far been lodged in Canberra and nearby Queanbeyan.

Emergency services worked through the night to respond to roof and window damage, fallen trees and electrical hazards.

Car windscreens were smashed at the Australian National University and Old Parliament House, while a wind gust of 117km/h was recorded at Canberra Airport.

The National Museum of Australia shut after the storm tore external roofing, damaged shade cloths and caused leaks inside the building. It reopened on Tuesday.

The Australian National Botanic Gardens, next door to the CSIRO, has been closed until further notice.

Local health authorities said fewer than 10 people presented to Canberra hospitals with injuries caused by the storm.

Many birds were injured during the storm, with a koel, raven, galah, cockatoo and magpie all treated at the Canberra Referral Hospital.

Australian Associated Press