Aviva does "tidying up" exercise with critical illness cover, according to an adviser.
The insurer has moved to "Activities of Daily Work" from "Activities of Daily Living" for applicants in higher risk occupations.
Aviva has also altered its definition of benign brain tumour claims. Formerly a claim was agreed on diagnosis, now it will pay if it causes permanent neurological deficit or invasive surgery.
The insurer has also removed the need for notification of a claim within a 26 week period.
Alan Lakey, founder of CIExpert and financial adviser, said: "The removal of the 26-week limitation is a sensible move reflecting the reality that many policyholders remain unaware that they have a valid claim until somebody points it out.
"The alterations are more of a tidying up exercise and the plan remains positioned towards the top of the CIExpert league tables in terms of potential future claims."
The age of children covered under the insurer's new critical illness policies will also be raised from 18 to 21 if the dependent child is in full-time education.
It follows changes made in July where the maximum child CI benefit was increased from £20,000 to £25,000.
Robert Morrison, chief underwriter at Aviva, said: "We're really pleased to extend our cover to help older children while they're still likely to be dependent on their families.
"If a parent needs to take time off work to care for a child who is seriously ill, the additional child CI benefit can offer some financial support, without affecting the sum assured. This can be a comfort to the family at a very stressful time."
Lakey added that previously Aviva had marketed an above average and competitively priced plan and the upgrade signalled an ambition to compete at the quality end of the market.
The changes will come into force on 26 November.
