Magen David Adom paramedics performed prolonged resuscitation efforts at the scene, but the women were pronounced dead.
Authorities said the women were apparently wearing sealed protective suits and collapsed due to a lack of oxygen following a malfunction. The circumstances of the incident are under investigation.
Fire and rescue teams and police arrived at the refinery and ruled out a leak of hazardous materials or any danger to the public or other employees.
Paramedic Hila Bizawi and medic Simcha Hasid said they received a report of two women who had lost consciousness at a factory near Ashdod.
“We arrived quickly and saw two women, around 50 years old, unconscious, without a pulse and not breathing,” they said in a statement. “We carried out prolonged resuscitation efforts including chest compressions, ventilation and medication, but ultimately had to pronounce them dead at the scene.”
The Ashdod refinery spans about 1,000 dunams (250 acres), employs roughly 400 workers and produces about 40% of the fuel and cooking gas consumed in the country.
The last fatal accident at the facility occurred in January 2013, when two workers, ages 35 and 38, died after inhaling hydrogen sulfide while repairing a malfunction without protective masks. An initial investigation at the time found they had failed to close a valve before fixing a pipe carrying hazardous materials, leading to a deadly gas leak.
Attorney Dafna Fischer, who represented the estate of one of the 2013 victims, said it was “tragic that fatal accidents allegedly linked to negligence and failures are recurring at the same workplace.” She expressed hope that the investigation would determine whether there had been a continuing failure to implement lessons learned from the earlier case.
The refinery said in a statement that a safety incident occurred in one of its laboratories for reasons that have not yet been determined. It said an in-house certified first aid team provided initial treatment until Magen David Adom crews arrived.
The company said it reported the incident to police, fire and rescue services, the Environmental Protection Ministry and other relevant authorities, and that it would conduct its own internal review.
On Tuesday, the Environmental Protection Ministry announced its intention to fine the refinery 32 million shekels over alleged air pollution violations. The refinery said it plans to appeal and denied the allegations. The facility has previously faced fines for air pollution offenses.