(Reuters) - A Boeing ( BA ) engineering union said on Thursday it will offer its representatives training on U.S. whistleblower laws for the first time, following concerns that its members lack adequate protection against possible reprisals.

The Society of Professional Engineering Employees in Aerospace (SPEEA) will hold sessions on Friday for shop stewards at Boeing ( BA ) and supplier Spirit AeroSystems ( SPR ) after receiving queries from members on how to become whistleblowers, a union director told Reuters.

Testimony at a U.S. Senate Permanent Subcommittee on Investigations in April raised questions over Boeing's ( BA ) treatment of whistleblowers. A Boeing ( BA ) engineer said at the hearing he was told to "shut up" and removed from a plane program when he flagged safety concerns.

Reuters could not independently verify the claims.

Boeing ( BA ), while not immediately available for comment on the union training, has previously said it has "zero tolerance for retaliation and encourage our employees to speak up when they see an issue."

The Federal Aviation Administration (FAA) said earlier this month it has opened an investigation into the Boeing 787 Dreamliner after an employee saw what appeared to be an irregularity in a required conformance test.

The company is going through a full-blown crisis after a door panel blew off a plane in January.

Union representatives will be trained to help members who want to raise safety concerns, said Rich Plunkett, director of strategic development at SPEEA's Seattle-area local.

Plunkett said SPEEA is trying to negotiate more robust protections through agreements with Boeing ( BA ) or through their contract.

Boeing ( BA ) has said it has held meetings in multiple countries to get worker feedback.

"When we find issues, we go as far as standing down a team to make sure that everybody on the team or everybody in the area is aware of the issue," Mike Fleming, a senior vice president at Boeing Commercial Airplanes, said in a statement.

"It's not meant to be punitive [and] we share the information across the programs."