Despite an independent report that found David Savage AM requires 24/7 personal care as a result of his injuries, Comcare, the federal workplace insurer, has agreed to pay for only 21.5 hours each week, the lawyers say.

They have appealed the decision in the Administrative Appeals Tribunal.

Mr Savage, a former federal police officer of 20 years experience, suffered devastating injuries in the bombing attack on March 26, 2012.

It was a young boy who was wearing the explosive vest.

To this day Mr Savage lives with traumatic brain injury, near complete loss of movement in his lower right limb, and post-traumatic stress disorder.

There was shrapnel lodged in his spine. Three soldiers were also wounded in the blast.

Mr Savage was flown to Germany for treatment and spent months in hospital in Australia.

It was the first time an Australian civilian was seriously injured since the war had started in 2001.

Mr Savage was an employee of DFAT and working for AusAID at the time of the attack. In 2014, he was made a Member of the Order of Australia for significant service to international relations through roles in development aid, peacekeeping and human rights abuse and war crime investigations.

In the years since, he has publicly detailed his recovery and rehabilitation efforts.

In a speech for the organisation Soldier On, which supports people affected by their service to the nation and their families, he described life changing and permanent damage. He had to learn to write and walk again.

"After a year and numerous nerve surgeries, I finally learnt how to walk again. However, two years ago, I had a set-back when some shrapnel in my spine moved, paralysing my right leg," he said in the 2017 speech.

Mr Savage claimed compensation from Comcare, the federal government's workplace insurer and Comcare has accepted liability for Mr Savages's injuries.

After an internal review requested by Mr Savage, it agreed to pay for 5.5 hours a week of household services and 21.5 hours a week of attendant care - personal care for help with matters such as bathing and dressing.

Comcare said 24/7 attendant care was not reasonable, because the assessment found Mr Savage had some ability to attend to those needs.

With regard to meals, for example, Mr Savage reported difficulty eating certain types of meals, in that he requires prompting to remember how.

But the review said that because Mr Savage only had difficulty eating some meals, it was reasonable that those meals would not be consumed without others to who he could look for guidance, and so five minutes, three times a day was reasonable to assist him with cutting and carrying food and prompting him to eat.

"Mr Savage has come to us to have this matter appealed on the basis he needs 24-hour, 7-days-a-week care, and noting that Comcare has limited that," his solicitor David Healey said.

"This matter has struck a chord with our firm, given the catastrophic nature of his injuries from Afghanistan and his declining health.

"Hence the need to have the tribunal independently assess his matter."

Of injury claims that ended up at the AAT in 2016-17, 45 per cent of decisions by Comcare were overturned.