From the outset, Twidle says he had health and safety issues.
Working at a large Christchurch construction site, Twidle felt the basic mask he was given to wear was unsuitable to combat the dust being produced by concrete being drilled and cut.
He says he repeatedly asked his NPL supervisor for a full-face respirator "to keep me safe" from silica dust.
But he claims his boss felt that the mask he was issued with was sufficient and met regulatory requirements.
Twidle says he became ill with a flu and chest cough, and believes that his sickness was linked to the dust exposure.
Twidle took three days off work - which spanned a weekend - and on his return, again asked for "a proper respirator".
"I was not happy with all the dust."
After messages back and forth with his supervisor, he says he was sacked via a text message.
"I have been contacted by site manager for [withheld] and he has advised you are not required on site and your final day will be Friday", the text message from his supervisor read.
"As I told you last Friday, I don't have any work available so I'm giving you notice your employment with NPL will terminate end of Friday 25th November 2016. I wish you all the best."
Twidle has since engaged lawyers who this week wrote a legal letter to NPL.
Twidle says he felt so embarrassed that he could not bring himself to tell his family and girlfriend that he had been sacked.
"For the next week, I set my alarm for 6am, got up, made my lunch as usual, got my work boots and work gear on, and pretended to go to work," he said.
"When Mum went off to work, I'd go home and try and fill in my day. I spent most of my day walking around Bunnings or walking the dog.
"I actually haven't done anything wrong but it still hurts your pride."
Twidle says he has felt "bullied" for wanting to be safe at work.
"Being a young guy, health and safety is a priority to me. It's been a horrible experience."
NPL was this week contacted to respond to Twidle's allegations.
A spokeswoman said they were unable to comment, however, saying they are "duty bound to respect the confidentiality of this personal grievance" and follow proper procedure, in line with the Employment Relation Act 2000.
"We would like to emphasis that the Health and Safety of all our workers, is of the highest priority," the NPL spokeswoman said.