Edna Calvert has been a weekly volunteer in her local charity shop since it opened 26 years ago.
The retired nurse found friends among her fellow volunteers - most of whom were also pensioners.
But aged 93, Mrs Calvert, from Downpatrick, County Down, will not return to the Cancer Research shop when it reopens, due to the threat of Covid-19.
"I have to take into consideration my age even though I don't feel it," she said.
"This virus leaves people nervous."
Many retailers in Northern Ireland are reopening after being forced to shut at the start of the coronavirus pandemic in March.
But Volunteer Now has warned that the loss of older volunteers, like Mrs Calvert, because of the pandemic, will affect the reopening of some charity shops.
Older people are more likely to become severely ill if they catch coronavirus, according to the NHS.
Twenty-five percent of volunteers in Northern Ireland are over 65, according to the Department for Communities and NISRA.
Mrs Calvert said charity shops like hers "depend so much on pensioners" but her age made her concerned about returning to work.
She said most of the other volunteers in the shop were over 70.
"Human beings need to mix with each other and it was enjoyable meeting our regular customers but there is a deadliness to this virus that is different," she said.
Mrs Calvert was one of 440 volunteers who helped raise £2.4m across 21 Cancer Research UK shops last year.
Julie Byard from the charity said shop volunteers, staff and customers were crucial to helping the charity "get back on its feet" as it faces a 25% loss in income next year due to the pandemic.
Ms Byard said they would follow government advice to determine who can help reopen stores.
There are 11,000 charity shops across the UK that help raise almost £300m for good causes each year.
Denise Hayward, from Volunteer Now, which supports volunteering in Northern Ireland, said older people "make up a substantial chunk" of regular volunteers.
She said there had been a distinct rise in the number of charities looking for volunteers in recent days.
'The new normal'
Ms Hayward said charity shops provided vital income for some charities, while the social aspect and structure offered by volunteering would be "difficult to replace" for those who can no longer go out in the same way.
"A number of shops have made it clear they are quite reliant on older volunteers and are concerned about their viability," she said.
"I think it is waiting to see what the new normal looks like and looking at different methods of volunteering, possibly online or at home."
Lynn Johnston, from Volunteer Now, is currently recruiting volunteers for charity shops in County Fermanagh.
"Charity shop managers are realising a lot of older volunteers will not be comfortable coming back. I am trying to help them fill the gap - it's a bubbling issue," she said.
"There is going to be a huge loss when they open their doors."
Matthew Allen, from Concern, said a number of its shops had been led by volunteers, most of whom are older, for more than 20 years.
"Older people make up the bulk of our volunteers, this issue across the UK is massive," he said.
"We may not be in a position to fully staff shops. There are difficult times ahead."
Mr Allen said it was important to look after volunteers who had contributed greatly to charities before the pandemic and said they had sent hand written letters of thanks to their volunteers during lockdown.
Meanwhile Caroline Storey, 51, from Enniskillen, County Fermanagh, said she has found a way to volunteer during the pandemic despite having to shield like many older people.
Mrs Storey, who has kidney disease, has volunteered for telephone befriending service Connect Fermanagh for the past five weeks.
She said she make the calls while on dialysis.
"I knew there would be a lot of people who would be worried or anxious and lonely at this time and I love chatting," she said.
"Many of those I talk to are shielding and lonely and I am also shielding so we understand each other.
"There are probably a lot of people like me who want to do charity work but can't because of their illness or age. This is handy - I don't even have to leave my house."