This industrial route to vinyl chloride was common before ethylene became widely distributed. When vinyl chloride producers shifted to using the thermal cracking of EDC described above, some used byproduct HCl in conjunction with a colocated acetylene-based unit. The hazards of storing and shipping acetylene meant that the vinyl chloride facility needed to be located very close to the acetylene generating facility. China still uses this method to produce vinyl chloride due to the large reserves of coal from which acetylene is produced.