AUTHORITIES are investigating whether a CSG contractor, who died on the outskirts of Roma on Sunday, had suffered heat stroke.
The temperature in Roma topped 41 degrees at 3pm that day.
Earlier reports suggest emergency services were called to treat him at 8pm, but was believed to have had a heart attack on the way to hospital.
He was pronounced dead on arrival.
The contractor company, Fluor Australia, is building the infrastructure that would deliver CSG from south-west Queensland to the Santos GLNG plant off Gladstone.
Fluor has launched an investigation into the death, meeting with workers on Monday and Tuesday to discuss the incident and any concerns.
In a statement, a Fluor spokesman said no cause of death had been confirmed but the company was working closely with authorities.
It would also have more discussions with workers.
"Further meetings with employees have been held (on Tuesday) and we anticipate that more meetings will be held with employees over the coming days."
Meanwhile, the ETU released a statement on Tuesday warning of its concerns that heat stress could prove a health risk to workers on the project, with some facing temperatures of up to 49 degrees.
ETU state assistant secretary Peter Ong said it had agreed with Fluor to meet on Tuesday morning, only to have it cancelled at the last minute.
Mr Ong said he wanted the firm to "sit down with our members and explain the situation, understand that workers had concerns and act in good faith" to deal with those fears.Santos directed all questions related to the man's death to Fluor.