Some plumbers are defying the lockdown doing non-essential jobs, at the same time that some cannot carry out essential plumbing jobs due to a lack of personal protection equipment.
The Master Plumbers organisation is calling on the government to act.
Plumbers are sharing stories online about call-outs they are refusing to do - but others are picking up.
"We had someone who rung up to get their new dishwasher installed," Master Plumbers chief executive Greg Wallace said.
"Our member said we cannot install that for you, it's non-essential.
"Two hours later they got a text to say, 'I got another plumber to install it for me'."
He believes 10 or 15 percent of plumbers were breaking the lockdown rules.
Hutt Plumbing and Gas general manager Colleen Upton is furious that others are encouraging the rule-breaking, such as a plumber who refused when a builder asked him to finish plumbing in a new, unoccupied home.
"The builder said, more or less, we'll get another plumber in and we won't give you anymore work. I mean, that's disgusting," she said.
Also, plumbing merchants who were selling products to tradespeople and home owners for clearly non-essential work, were creating risks, she said.
She turned down a request earlier this week to supply a part for gas heating to a home owner, only for them to quickly source it from a plumbing merchant nearby; and refused another home owner who wanted his taps tweaked.
Online, another plumber wrote: "Had a tenant tell their landlord their kitchen sink was badly blocked and was overflowing. Turned up and it was their ensuite basin! Wasn't impressed."
And another: "I had someone with a leaking slide shower hose insisting it was urgent. I said, but it's only leaking inside the shower ... I explained what was essential works and they hung up."
Those plumbers who were doing such jobs were not only stealing work from those obeying the lockdown, it was worse than that, Upton said.
"People like that are the ones who could make this lockdown go longer than four weeks," she said.
"Plumbers are there to protect the health of the nation ... Plumbers who aren't adhering to essential work are not honouring that industry tradition and belief. What they're doing is putting everybody else at risk."
The flip side is where plumbers were needed for essential jobs, such as unblocking toilets in people's homes, but lacked the protective gear to work safely.
Hutt Plumbing and Gas acted early to get PPE, but still faced running out, Upton said.
"For the mask side of it I could see that for us, by the end of next week we could well be in that situation," she said.
"I wouldn't ask them to go without it. I couldn't do that. It's not fair of me to sit behind a desk and put my staff in that position."
Master Plumbers chief executive Greg Wallace said some essential jobs had had to be put off already due to lack of PPE.
Master Plumbers last Friday asked the Ministry of Business Innovation and Employment (MBIE) to intervene, by closing down some plumbing merchants it said were supplying products for non-essential work.
"In our view, these stores should only be able to provide emergency callout supplies to those doing essential services, as otherwise this increases the risk to their staff, tradespeople and the general public," it told MBIE.
Master Plumbers also asked the ministry to force all plumbers, gasfitters, and drainlayers to keep a record of all work done during lockdown.
"This could then be spot audited at a later date, including reviewing invoices to ensure that only essential work was done."
It had not heard back from MBIE, Wallace said.
RNZ approached MBIE for comment
The work allowed was very limited, he said.
"Major water leaks, hot water cylinders, unblocking sanitary waste pipes, or gas servicing where there's a potential leak or issue with the gas system. So really defined and quite a tight regime."
The Ministry of Health told him it would try to help plumbers with PPE, but did not hold out much hope, he said.
- If you have symptoms of the coronavirus, call the NZ Covid-19 Healthline on 0800 358 5453 (+64 9 358 5453 for international SIMs) or call your GP - don't show up at a medical centre
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