"Where a zone contains both general lighting and display lighting, and for the selected activity SBEM assumes the presence of display lamps, then the display lighting and the general lighting must be entered as ‘display’ and ‘general’ lighting respectively. Where a zone contains both general lighting and display lighting, and for the selected activity SBEM does not assume the presence of display lamps, then the zone must be subdivided to create additional ‘display’ zones to represent the display lighting. A suitable ‘display’ activity should be used for the ‘display’ zones and appropriate lighting entries entered. The remains of the original zone must have the original activity and only the general lighting is entered into the zone(s). Where a zone contains a mixture of lamp types providing general lighting (no display lighting) across the entire zone, such that simply splitting the zone to reflect the lamp’s locations is not practicable, then the following method should be followed. 1. The proportion of the zone’s area lit by each lamp type should be established. 2. The zone should then be split into a number of zones to match the number of lamp types and for each lamp type the relevant proportion of the zone area and all of the zone’s envelopes, including glazing, should be entered into each relevant zone along with the appropriate respective lamp type."