IKEA Strala Manual De Instrucciones página 9

Replace any faulty lamps with ones of the same voltage
rating and manufacture, check the box for details. Spare
lamps are usually provided with the set.
Lamps should not be removed or installed with the
supply on.
Only replace 'fused' lamps (sometimes identified by a
white mark on the glass) with identical 'fused' lamps.
Installation on Christmas Tree
Christmas trees because of the pine oils, and particularly
after being in a heated room for a week or two, are very
flammable. Tree decorations may also be flammable and
should be kept clear of the lamps as far as possible.
Christmas trees should be mounted securely so that they
are unlikely to fall over, or be knocked over by children
or pets. They must be kept clear of heat sources,
including spot lamps and particularly CANDLES.
Take care when decorating the tree, use a stepladder if
the tree is tall and wear shoes. Many more accidents are
caused by treading on plugs and lamps in bare feet than
faulty electrical equipment.