Writing "Read this," Baldwin on Tuesday reposted lengthy remarks from Terese Magpale Davis, who worked in the wardrobe department on Rust.
"I'm so sick of this narrative," Davis wrote.
"The story of us being overworked and surrounded by unsafe, chaotic conditions is bulls**t."
On October 21, cinematographer Halyna Hutchins was killed by a bullet discharged from a gun Baldwin was using to rehearse a scene on the Rust set in New Mexico.
The 30 Rock actor had been told the weapon was "cold," or safe to use, according to court filings by the Santa Fe Sheriff's Department, which is investigating the incident.
Camera operators had walked off the Rust set before the incident to protest working conditions, authorities have said. Santa Fe County Sheriff Adan Mendoza last week said he believed there was complacency on the production regarding safety.
Lawyers for the armourer in charge of the weapons used in the filming said the production was unsafe due to various factors, including a lack of safety meetings.
Davis, however, said the crew had several safety meetings, "sometimes multiple per day".
The production team "were some of the most approachable and warm producers I have ever worked with", she added.
"Concerns were heard and addressed."
Davis did not immediately respond to a request for comment.
Baldwin, who also served as one of the movie's producers, has said he is heartbroken and will support limits on the use of real guns on film and TV sets.
Production company Rust Media Productions said it had not been made aware of any official complaints and has hired a law firm to investigate the incident.