Scaled Composites could still face a criminal or civil prosecution over the explosion that occurred on 26 July 2007 killing three of its employees.

The California Occupational Safety and Health Administration's (Cal-OSHA) bureau of investigation is now preparing and evaluating its evidence before submitting it to the Kern county district attorney's office for review. That office will then decide whether a prosecution takes place.

On 18 January the Cal-OSHA published its investigation's citations of failures by Scaled in relation to the 26 July incident and notified the company of a set of fines totalling $25,870.

Scaled had 15 working days from 18 January, which is until 8 February, to pay the fines or appeal them. The appeal process can take up to a year to reach a hearing and would not stop any resulting civil or criminal prosecution.

The citations specify alleged failures by Scaled to adequately train its personnel in the use of substances such as nitrous oxide. It was a cold flow test of nitrous oxide that led to the explosion.

"Our investigation just covers this case from a safety in the workplace perspective. When cases close, we then refer them to the district attorney's office to assess whether there are any criminal or civil issues involved. That usually takes months, at least six months. It depends on [CAL-OSHA's] workload, the complexity of the case, a lot of variables," says Cal-OSHA.

On 23 January Scaled president Burt Rutan said in New York that the exact cause of the explosion was still unknown. He added that the company was working with local authorities and aerospace consultants to find out exactly what had happened.