They are used along with peak expiratory flow to help define the green, yellow, and red zones of your asthma action plan.

To the uninitiated, the Strip is divided into three loosely defined zones.

The classic division of labour between a head and class teachers, each with clearly defined roles and 'zones of influence'.

The electrocorticogram is still considered to be the "gold standard" for defining epileptogenic zones; however, this procedure is risky and highly invasive.

For swimming pools, Section 603 of BS 7671 defines similar zones.

The player must define zones, each having limits on the kind of development that can occur there.

They define the boundaries between the belt and the adjacent cratons and separate internal zones within the belt.

There are still other complicated issues, like how to define geographic zones in Europe in which additional weapon ceilings would be imposed.

I now turn to the most pressing concern today, which is over the procedures in place for defining no-flight zones in the EU.

The continued disruption to European airspace has once again put the procedures applied for defining no-flight zones under the spotlight.