If a large leak of refrigerant occurs such as from a filled cylinder in an enclosed area what action should be taken when no self-contained breathing apparatus is available?

If a large leak of refrigerant occurs such as from a filled cylinder in an enclosed area, the correct action that should be taken when no self-contained breathing apparatus is available would be to vacate the spill area and ventilate it. Leaving the area of the spill should be done as fast as possible to avoid suffocation of the refrigerant or other health effects like burns and irritations. Also, diluting it with air or ventilating it would make it less harmful to the people affected by the spill as it would be less harmful than being in its concentrated form.