The recent devastating earthquake and tsunami in Japan highlighted the complexity of business interruption claims and supply chain risks, and risk managers should review their insurance programs to ensure that they are not left holding large losses when disaster strikes, a panel of experts advised.

The repercussions from the quake’s disruption are so widespread that they touch operations throughout the world, said the panelists, who spoke during a “hot topic” session Tuesday at the Risk & Insurance Management Society Inc.’s annual conference in Vancouver.

Estimated insured losses from the quake and tsunami range from $21 billion to $34 billion, said Holly Daley, director, global risk management at Hitachi Data Systems Corp. in Santa Clara, Calif. “Of the exposure in Japan, about 14% was insured for earthquake,” she said.

Business interruption and contingent business interruption coverage, though, was not widely written in Japan to cover losses from the catastrophe, Ms. Daley said. “A very small single-digit percentage” of such losses were likely covered, she said.

Companies in other parts of the world that experienced interruptions in their operations because supplies were curtailed from Japan also are mostly uninsured for those losses, according to the panelists.

Business interruption insurance generally is triggered only when there is damage to the policyholder’s property, which leaves a lot of companies uninsured for those losses as a result of the Japan earthquake, according to Duncan C. Ellis, managing director and U.S. property practice leader at Marsh USA Inc. in New York.

“You can buy standalone contingent time-element coverage specific to certain suppliers” that covers losses whether there is property damage or not, Mr. Ellis noted. “Butvery few people purchase it,” he said.

Only such risk-savvy firms as semiconductor and automobile companies that rely on critical supplies from Japan are likely to have such coverage in place to respond to the quake-related losses, Mr. Ellis said.

Nancy Sher Cohen, a partner at Los Angeles law firm Proskauer Rose L.L.P., urged risk managers to consider buying “all-risk” coverage for interruptions that would cover losses stemming from named suppliers.

Otherwise, coverage likely will only be triggered if the peril that caused the supplier’s loss is named in the policy, Ms. Cohen explained.

“All-risk policies,” on the other hand, generally cover damage that results from a peril as long as it is not excluded, said Ms. Cohen.

Risk managers that have claims related to the quake—whether their companies are in Japan or elsewhere—should file those claims as soon as possible, Ms. Daley urged.

“These claims are going to be very complex; they’re just starting to come in, which is typical. Two or three months after the event is when you are going to start seeing them,” she said. “I think good advice in this case is to be one of the first…start getting your documentation in now because it is going to be much more difficult in six months.”

RIMS President Scott B. Clark, who was in Japan during the earthquake, said he expects fallout from the catastrophe will show up in the form of higher premiums and restricted coverage.

“This is certainly going to be a game-changer,” said Mr. Clark, who is risk and benefits officer for Miami-Dade County Public Schools.