The Film Production insurance policy contains an exclusion under the Cast Insurance coverage for a person injured when taking part in a hazardous stunt or any special effect in the declared production, without the prior consent of the insurance company.
Although these types of activities are usually reserved for stunt performers, the producer and the director should be aware of this exclusion. If actors are involved in hazardous stunts or special effects, please advise your broker well in advance so that they can make the appropriate arrangements with the insurance company.
Additional information may be requested. The underwriters may cover the scene based on the strength of the information — the Stunt Coordinator resume is particularly important; otherwise, the underwriter may charge an additional premium, or apply a higher deductible or impose a sub-limit on the limit of coverage, or, they may use a combination of all three to address the risk.
If you are comfortable with a high deductible and sub-limit, you can often save the cost of an additional premium being charged.
Be sure to talk to your broker before you film any stunts or SPFX scenes that were not originally in the script that your broker provided the insurance company.
See also: Producers Should Disclose All Stunt Activity to Their Film Insurance Broker (Vantropolis podcast)