Signals after dark

Signals after dark

Urban street lighting plays a vital role in our everyday life, and its practical value is apparent in a variety of situations without us (9) ________ being aware of it. The importance of good lighting for us humans must derive primarily from the need for safety, (10) ________ there is also a similar function in stations and tunnels to act as a warning of blocked exits or rapidly approaching trains. In addition, amber is the glow you see in the centre of a lantern, and on the horizon (11) ________ the evening sun is setting. In modern life, lighting marks hazards and boundaries, and the sight of it automatically (12) ________ us more alert. It is used for platform signs showing restrictions, on doors for emergency exits, on controls that will produce dramatic results if pressed during engineers’ inspections. It is also a feature of public signs and (13) ________ events. Well-lit streets and busy parks have always been closely connected with public reassurance, (14) ________ the extent that streets with repeated accidents were often redesigned by planners during the last decades in the reasonable belief that they had (15) ________ much darkness around them. Here, however, we can perhaps see another reason for light as guidance; if you see a crossing growing dark in the evening, it is often best to beat a hasty retreat, (16) ________ traffic arrives.