Minimize your risk and liability with Halogen's Emergency Gas Shut-Off Valves. If you use hazardous or Chlorine Gases you know the risks associated with them. Halogen's Emergency Gas Shut-off Valves provide an extra measure of safety for these environments. Don't let a gas leak become a reportable Hazmat incident. Protect your personnel and environment. All of our shutoff systems are Fire code approved replacements for gas scrubber systems.