Employer pressure to overwork their voices has caused performers to taste blood, faint, lose their voices for months at a time and suffer permanent damage, says the union.

Voiceover work might seem to be the most relaxed sort of acting at first glance, but if it’s videogame v.o., it might not even be safe, contends SAG-AFTRA, which has been having negotiations on and off with a group of game companies since the AFTRA Interactive Agreement expired at the end of 2014. Now, frustrated by the industry’s alleged refusal to respond to a vocal safety proposal, the union has asked California occupational safety regulators to investigate.

“Increasing numbers of voiceover actors are reporting that they are experiencing both short-term and/or long-term damage to their vocal cords, due to the intensity of the vocal demands put on to them by the employers,” says union national executive director David White in a letter to Cal/OSHA’s regional manager. “For up to four hours, actors are asked to perform not just voices, but noises, death screams, creature voices, combat yelling and other sounds, with so much force and explosive vibration, that they are causing internal damage to their vocal cords.”

Asserting that two medical specialists “have documented that the vocal stress from video games is causing medical problems that include vocal nodules, cysts, polyps and, in some cases, cord hemorrhaging,” the May 25 letter requests “a thorough investigation of industry practices.”

The missive appeared on the union’s website without public announcement, in connection with a May 26 note that says union members have reported “losing their voices for up to six months, tasting blood during their session, fainting or nearly fainting, and damage resulting in a permanent change to vocal range.”

An earlier post, dated Feb. 5, complained that “the employers have not given us a substantive response to our vocal safety proposal” and said that the union would therefore “be exploring other options to protect performers,” including contact with Cal/OSHA.

The industry’s chief negotiator, attorney Scott Witlin, did not respond to a request for comment. A Cal/OSHA spokesman told The Hollywood Reporter that the agency “is still researching and reviewing the issues,” and added that state law “requires employers to provide a safe and healthful place of employment, and … correct unsafe or unhealthy conditions, work practices and work procedures in a timely manner.”

The SAG-AFTRA letter says that the union recommends shortening vocally stressful v.o. sessions “without a loss in compensation,” a condition that may be outside Cal/OSHA’s powers. A union spokeswoman declined to comment, citing a press blackout during negotiations.