Avoiding contact with the public was one way to keep staff safe and maintain their ability to offer services, he said.
The pharmacy is only selling standard disposable masks in five-packs. The N95 surgical masks cost several times more than that and are only needed in hospital and industrial situations.
"They've been shown to be not hugely beneficial for the general public. Basic face covering, if everybody is doing it, will do the job," Holmes said.
The pharmacy hasn't needed to enforce mask wearing by customers.
"We expect and hope that everyone does their bit," Holmes said.
It was similar at Central City Pharmacy, where customers shop at a counter in the doorway. Most of them were wearing masks, retail assistant Sophie Barron said.
Quite a few have made their own.
"I saw one lady wearing a Star Wars one, which was quite cool."
The pharmacy has sold out of reusable cloth masks and is selling packs of 50 disposables, and individual disposables.
At Pharmacy 145 on Victoria, owner Evan Lee has not blocked the entrance but limits customers to one or two at a time. He is selling lots of masks of both kinds.
He said it was not his role to enforce mask wearing, and some people might not know it is mandatory.
"I have even given a mask to one of the homeless, who said he can't afford it."
Customers at Aramoho Four Square had been good about mask wearing, owner John Sharp said.
It was similar at BP2go in Taupo Quay, where there is a poster outside warning masks are mandatory. Some customers who were without one have had to leave, a staff member said.
Countdown spokesperson Kiri Hannifin said masks were mandatory inside their stores. Customers were told so by signage, and masks were available to them.
Police had advised the store not to force the issue if people refused to wear them and became aggressive.
Countdown supermarkets are limiting purchases of products like toilet paper, flour, rice and petfood to six items at a time.
Foodstuffs, which owns Pak'n Save, New World and Four Square, is turning away customers who are without masks. Everyone over 12 is expected to have their nose and mouth covered, unless they are exempted due to being under 12 or having a health condition or disability.
Staff at the door were managing numbers in the store and face coverings. Anyone becoming aggressive would be referred to police, corporate affairs head Antoinette Laird said.
Foodstuffs is paying an extra 10 per cent to frontline and distribution staff working during level 4, in appreciation of their efforts.
Covid-19 is an airborne virus, spread by droplets when people speak, cough, laugh or sneeze, the covid19.govt.nz website says. Masks are mandatory in all indoor public spaces and on public transport. Wearing one protects both the wearer and others.
Masks need to fit the face snugly to work.
Disposable masks should be multilayered, have a wire to shape them over the bridge of the nose and not be wet or dirty. They should be thrown away after each use.
Reusable masks should also be multilayered, made of tightly woven and breathable material and have a nose wire.
A good mask, if held up to a light, should block out most light, the United States' Centres for Disease Control says.
The covid19.govt.nz site gives instructions on how to put on and take off a mask - not touching the mouth parts, and washing hands before and after. It warns not to share masks, to wash reusable ones in detergent and hot water and dry them thoroughly before wearing.
It also gives tips for making simple and effective face coverings.
