Should one leave the house during polyurethane application?

It depends on the place that will be insulated. For example, if you insulate a basement which is separated from the house by a closed door, it’s not absolutely necessary to leave.
However, if there are children, we recommend that they are kept outside the house.

The Standard for Medium Density Spray Applied Rigid Polyurethane Foam Thermal Insulation states that for any inhabited building or structure, the location where urethane foam insulation is installed must be insulated / protected.

In addition, the standard requires that the places where the installation is performed must be ventilated, during the time of installation and after installation, according to the time period declared by the manufacturer.

The contract provides that the minimum ventilation rate is 0.3 air changes per hour.

Some manufacturers require the ventilation to be maintained for a period of 24 hours after installation of their polyurethane foam.