A "perfect storm" of factors relating to ventilation and unsealed ducting allowed poisonous gases to rise into a Co Cork hotel room where a woman died, the defence lawyer for a plumber on trial for manslaughter claimed yesterday.

A plumber on trial for manslaughter arising out of a gas leak at the Trident hotel in Kinsale, Co Cork, had told gardaí he had tested the boiler for possible leaks with a computerised testing device. But the accused later stated he had not done so.

Deadly carbon monoxide gases can mimic bugs such as the common cold or flu, a pathologist said yesterday.

A plumber incorrectly converted a gas boiler leaving it spewing out lethal quantities of carbon monoxide causing the death of a woman staying at the Trident hotel in Kinsale in January 2011, it was claimed by the prosecution at the opening of a trial yesterday.