Space underneath stairs

[Guest jean yeomans]

We recently bought a townhouse which has a garden on the upper level and not on the ground level.  To access the garden there is a metal open tread staircase rising from ground level to the second level.  Our neighbour has a right of way up the stairway to access his garden.  The land beneath the stairs belongs to us, forming part of our plot. Can we store items such as bins, garden equipment underneath the stairs ?

[AnthonyB]

If it isn't a fire escape route I don't see any reason from a fire point of view