This scrap of paper was the last line of defence for two workers inside the Forrestfield-Airport Link tunnel.

Had someone hit a switch, the two men, working out of sight, would have been cut to shreds.

Failure to properly tag and isolate dangerous machinery and lines in the underground tunnel has been one of the gravest and most repeated safety breaches inside the 8km tunnel.

The pathetic attempt at a warning sign was photographed by a tunnel boring machine supervisor last year.

He eventually quit because he feared someone would die on the trouble-plagued $1.8 billion project. But not before he passed detailed information to the State Government on a litany of pressing safety issues.

But that backfired when he was outed as a whistleblower to his bosses by a bungling government official.

Minister for Industrial Relations Bill Johnston had promised to protect the supervisor’s identity when he received the information via the supervisor’s wife.

Play Video Meet the Perth families at the end of their tethers over the Perth Airport Link tunnel construction. Meet the Perth families at the end of their tethers over the Perth Airport Link tunnel construction.

Mr Johnston’s staff later apologised to the wife when the information was forwarded to the head contractor, with the supervisor mistakenly identified.

The Sunday Times understands an official with the Public Transport Authority was responsible for the confidentiality breach.

The supervisor said it put him in a very awkward position with his superiors, who challenged him, while some of his colleagues wouldn’t speak to him afterwards.

Mr Johnston was also angered. “I was very disappointed that the whistleblower was outed and I’ve made sure that it won’t happen again,” he said on Friday.

Camera Icon Tunnel workers with no fall protection, standing on slippery muddy pipes. The red cable they are near is high voltage. Credit: Supplied

“I personally followed up on the situation at the time, and I’ve also personally been to site to speak to workers as well.”

The supervisor, who has almost 20 years of tunnelling experience from around the world, said he quit the project because “the safety, quality and whole project itself was so poor I did not want to be a part of it any longer”. “It was extremely bad — the worst I have ever seen,” he said

The Sunday Times’ story last weekend on isolation breaches reminded him of the the scribbled warning sign, stuck to a control panel while two workers were inside a 10,000-litre tank fixing blades on agitators.

“There was no other warning, not even a danger tag,” he recalled. “It wasn't even covering the actual switch. If turned on it would kill them — tear their arms and legs off.” He raised the issue with a superior. “This is how we seem to be isolating,” he wrote in an email.

In another email, he wrote: “I feel it needs to be brought to your attention that the process of reporting hazards and incidents is not valued by the workers, whether it be due to actual or perceived issues.

“The general feeling amongst the workers is that if they speak up or place their names on hazard cards, that they will be labelled as trouble makers or their employment on the project will be jeopardised, regardless of their work ethic being at a high standard ...It is mind boggling how many workers are coming to me to vent about the failure of the process and it’s difficult for me to continue to attempt to reassure them.

“Just one example of this was on night shift last week, where some workers were instructed to carry out high risk work (thrust frame dismantling) without a SWMS, SEA card or any other required documents and the instructions they were given were obviously dangerous. A hazard was raised anonymously and within minutes the workers were confronted by supervisors and management, demanding to know who wrote the hazard —which has not been seen or heard of again since.”

The hazards mentioned in the information passed to Mr Johnston included dangerously deficient pipe brackets, substandard valves, faulty rigging equipment, blocked walkways, missing safety equipment, workers scaling wet and slippery pipes to turn off valves, smoking underground and working at heights with no fall protection.

They were investigated by WorkSafe WA.

“A senior inspector visited the site after this contact, and eight improvement notices and one prohibition notice were issued dealing with the matters raised in the complaint,” a WorkSafe spokeswoman said.

The supervisor’s wife, who worked in occupational health and safety and had met Mr Johnston and a safety symposium, wrote to him: “My husband is in an awkward position as he really needs this job, however he is fearful that there will be a fatality at the project.

“He encourages the crew to speak up when something is unsafe, however there are many workers, supervisors and superintendents who don’t seem to understand the risks. There are also numerous workers on 457 visas who don’t speak English and are desperate to maintain their employment and will no doubt do whatever they are told.”

“Hazards, incidents and injuries are often documented by workers (but) seem to disappear,” she wrote.

A separate issue was raised by hyperbaric workers in the tunnel, the supervisor said.

Like divers, these workers operate in a pressurised environment — a compressed air bubble — when performing maintenance on the tunnel- boring machine’s cutting tools. When the machine is below the water table or the soil is not stable, the air bubble is needed to support the ground in front of the cutter head.

“The (air) pressure had been dropped on them while they’re working (which meant they could work for longer and required less time in decompression afterwards) and the face (of the ground) started to collapse,” he said.

Salini Impregilo-NRW JV project director Richard Graham said “without further details it is difficult to comment on such an assertion; however we strongly refute their inference.

“Hyperbaric interventions are a very critical and delicate activity which are undertaken with the utmost care and attention to safety. They are carried out to enable the cutter head of a tunnel-boring machine to be maintained when it is under water.”

Camera Icon Messages relating to the election of safety representatives. Credit: Supplied

He said SI-NRW JV was “committed to the safe and successful delivery of this project”. “We have reviewed and optimised our isolation process and retrained our teams. We have also introduced additional checks and controls to the normal tunnelling procedures.

“For the next four to six weeks we have increased supervision during the implementation of the new isolation process, with supervisors and/or safety coordinators required to oversee the procedure.

“Our primary goal is to reach the end of each day with no safety incidents and we do not hesitate to make improvements that are identified to reduce any risks.”

However, The Sunday Times can reveal that a bid to elect a safety representative on one of the tunnel teams had to be scrapped last month when a manager informed workers on a group phone message that “I don’t want to sacrifice production for any stupid election”.

Mr Graham responded that health and safety representatives were voluntary positions strongly encouraged by SI-NRW. It has 15 across the project who represent the workforce on the Project Safety Committee. “On 5 January 2019 an unscheduled vote was called without notice. The lack of notice, coupled with a reduced workforce on site due to the Christmas break, led the tunnel superintendent to recommend the vote be rescheduled until the full complement of team members had returned to work.”

A spokesman for Transport Minister Rita Saffioti said the State Government “is doing all it can within the limits of the contract to ensure safety is top priority”.