Four companies served with prohibition notices over engineered-stone safety concerns have been named by the Health and Safety Executive (HSE). The regulator said in June that inspectors had served the firms with prohibition notices after finding they were not keeping workers safe. The companies, which were not initially named because they could have appealed, also received improvement notices and could face follow-up inspections. It received two prohibition notices relating to dangerous machinery and one for the silica risks, on 30 April. Loading…In May, the HSE warned against dry-cutting engineered stone, also known as artificial stone or engineered quartz.