SAFETY PHONE GUARDS AGAINST EXPLOSIONS (Mar, 1935)
If they had already perfected explosion-proof telephones in 1935, why can’t I use my cell phone at the gas station? Has this miraculous technology been lost?
SAFETY PHONE GUARDS AGAINST EXPLOSIONS
A new type of explosion-proof telephone, exhibited in Chicago, is a recent addition to the roster of curious safety appliances developed especially for use in industries where dust, gunpowder, or inflammable gases present the constant hazard of a blast. Not only does the construction of the instrument guard against the possibility of an electrical spark igniting any combustible material in the surrounding air, but even the mechanical working parts have been designed particularly with a view to reducing friction so that a spark cannot be produced.