Safety requirements for your creche or pre school set down by the HSE..

Child Care (Pre-School Services) (No 2) Regulations 2006 and Explanatory Guide to Requirements and Procedures for Notification and Inspection

:section 27 (a)

All fixed heating appliances e.g. radiators and storage heaters must be

protected by a guard or be thermostatically controlled. Where individual

heating appliances are provided, they should be of a type which does

not have an exposed flame or heating element which could provide an

ignition source. These must be protected by a guard or thermostatically

controlled. ..

In other words you can fit a thermostat but you will need to keep it so low it will not heat the room...

Radcovers are far safer and will also prevent bad bangs against the steel rad.