[5] CFC-11 is a Class 1 ozone-depleting substance which damages Earth's protective stratospheric ozone layer.

The replacement, dichloromethane, boiling point 39.6 °C (103.3 °F), requires a higher ambient temperature to work.

Prior to the knowledge of the ozone depletion potential of chlorine in refrigerants and other possible harmful effects on the environment, trichlorofluoromethane was sometimes used as a cleaning/rinsing agent for low-pressure systems.

[6] In 2018, the atmospheric concentration of CFC-11 was noted by researchers to be declining more slowly than expected,[10][11] and it subsequently emerged that it remains in widespread use as a blowing agent for polyurethane foam insulation in the construction industry of China.

[13] In 2022, the European Commission announced an updated regulation that mandates the recovery and prevention of emissions of CFC-11 blowing agents from foam insulation in demolition waste, which is still emitted at significant scale.