Tarenni Colliery 1858, when the Primrose Colliery was owned by Morgan and Lewis, fumes of an engine boiler suffocated 14 men and boys, and 7 horses. According to HM Inspectorate of Mines and Quarries data, outside the Gwendraeth valley, Tarenni Colliery had the highest set of recorded incidents for coal damp and methane gas explosions. In total during its production lifetime, there were six outbursts in which three men lost their lives: one on 12 December 1914; two on 17 February 1941. On 1 November 1909, water from the abandoned Ynysgeinon pit caused the death of five miners at Tarenni No.2. On
Mines in the Battle of Messines (1917) on 7 June 1917, the mines at Messines were fired within the space of 20 seconds. The joint explosion ranks among the largest non-nuclear explosions of all time and surpassed the mines on the first day of the Somme fired 11 months before. The sound of the blast was considered the loudest man-made noise in history. Reports suggested that the sound was heard in London and Dublin, and at Lille University's geology department, the shock wave was mistaken for an earthquake. Some eyewitnesses described the scene as "pillars of fire", although many also conceded that the scene was indescribable. The