The Television Act makes specific provision for the insertion of advertisements not only at the beginning or the end of a programme but “in natural breaks therein”. This arrangement allows an even spread of the advertising and does not militate against long programmes which might otherwise be followed by impracticably long periods of advertising. In variety and light entertainment programmes, the succession of items offers a succession of natural breaks between them. In sports programmes there are natural breaks between events. Panel games contain obvious natural breaks between rounds of questions or when one contestant gives way to another. For much of the rest of the television programmes, the theatrical convention is observable—breaks marked in presentation by a change of scene, a significant lapse of time or a new sequence of events which in the theatre may coincide with the dropping of the curtain between two or three acts, or the darkening of the stage between scenes.
Some overseas broadcasting authorities aim to reduce the length of individual intervals of advertising; some also limit the number of advertisements that may appear in an interval. This has the effect of increasing the number of advertising intervals, in some cases to an average of five or six an hour. The Authority, however, has been concerned to keep the number of intervals down by extending their length as far as may be consistent with good presentation of both programmes and advertisements. There may be up to three minutes of advertising in intervals between programmes and up to two minutes in an interval in a 30-minute programme. Other intervals carry up to 2½ minutes. Numerical restrictions agreed between the Authority and the programme companies provide that, as a general rule, advertising intervals are restricted to two in the course of a programme of one or 1½ hours and one in a 30-minute programme. But not all programmes have advertising intervals and some 60-minute programmes have only one; and by agreement with the Postmaster-General, advertising may not appear within two minutes of the beginning or the end of programmes broadcast to schools, religious programmes and any broadcast of a formal Royal occasion.
As a result of these policies, the number of advertising intervals at the beginning and the end of programmes and in natural breaks is on average no more than three an hour over the evening and fractionally less than three an hour over the day. Taking the evening hours of 6-11 p.m. in a typical week in 1962, the figures were:
|Number of programme hours||35|
|Number of programmes||67|
|Number of advertising intervals (including the interval at the end of the final programme in each period of five hours)|
|(a) Between programmes||57|
|(b) Within programmes||47|
These 35 evening programme hours included 30 with three advertising intervals, three with four intervals, one with two intervals and one with no interval.
Taking the whole of an average week in 1962, about 115 programmes were transmitted from a single station. Of these:
40 programmes had one internal break selected for the insertion of advertisements. While most of these were half-hour programmes, the group included one or two longer documentaries and three of the 60-minute plays: Probation Officer, Television Playhouse and Armchair Theatre.
20 programmes had 2 internal advertising intervals. These included 60-minute variety programmes and westerns and the 90-minute Play of the Week.
Since the introduction of Independent Television, the permissible amount of advertising has included not only an average of six minutes of spot advertising an hour, but also a limited number of advertising magazines. This form of advertising has been relatively popular with many viewers. After consultation with the Authority, however, the Postmaster-General decided that the magazines should be discontinued after 31st March 1963.