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1 - Quality of audio-visual equipment and visual displays
When designing lecture theatres, it is best to seek advice from specialist audio-visual suppliers, installers or consultants. BS 8205:1985 is no longer worth looking at as it predates the introduction of laptops, internet access and data projectors. Visual displays need to accommodate visually-impaired users. Contrast is the key, so dimmable lighting around the screen area is advisable. Distance from the display is also critical – 12 rows is the limit for writing boards and flipcharts.

2 - Desk space
The more desk space the better, so fixed tablet arms (small desks) are inadequate. Alternatives include pivoting tablets (for example, the Griffin Tablet), hinged writing shelves and fixed tables. David Adler, author of Metric Handbook, suggests a writing surface depth of 250-450 mm. Seat widths (525-750 mm) and back-to-back spacing (850 mm minimum) are also suggested but would be costly to implement. Fixed tables need about 1500 mm back-to-back, but would be regarded as too widely spaced for most university budgets. Left-handed students need to be catered for: where smaller writing tablets are provided, about 13% should be for left-handers and marked accordingly.

3- Internal acoustic quality
Ensure your building complies with Part E of the ºÚ¶´ÉçÇø Regulations, which now covers education buildings. DfEE's ºÚ¶´ÉçÇø Bulletin 93 Acoustic Design of Schools is a useful first port of call. The web version (www.teachernet.gov.uk) links to spreadsheets of absorption co-efficients and sound reduction indices, and to a spreadsheet that calculates facade insulation and reverberation times, run by BRE. (www.projects.bre.co.uk/envdiv/school_acoustics).

4 - Seating comfort
As comfort correlates to productivity, the seat should fit different peoples' shapes. Current recommendations for minimum seat width are based on old ergonomic data. An Australian survey in June 2003 showed that women are taller (by 1–2%) and heavier (by 10–20 kg) than they were in the 1920s. As a result, designers at Melbourne Cricket Ground, for example, are allowing 30% more space per patron, 20 mm extra seat width and more legroom. Seating needs to be strengthened, too. For UK data, see National Sizing Survey website (www.size.org).

5 - Natural and artificial illumination
Students like natural light. Unfortunately, natural light is not a priority for designers as it gives rise to problems such as glare, heat load, distraction and blackout difficulties. These can be overcome with clerestory lighting. For advice on artificial illumination refer to CIBSE Lighting Guide LG 5 Lecture, Teaching and Conference Rooms (1991).

6 - Ventilation
Stuffy lecture theatres clearly don't add to the learning experience – trapped carbon dioxide in theatres is responsible for dozing students (and lecturers). CIBSE recommends a ventilation rate of 8 litres/second/person, three or four air changes per hour for displacement systems and 6-10 for high-level systems (which are noisier and more expensive to run).

7 - Occupancy level
Adler suggests that an average-sized lecture group is 30-60 students, so larger theatres are not justified. Indeed, he reckons theatres are often under-used. However, students do not like the crowding that results from full lecture theatres, so theatres should perhaps seat more people than strictly necessary. Or, if the personal spaces were more generous (with wider clearways along seating rows), then there could be the same number of seats as people. Such a theatre might not feel full even if all seats were occupied.

8 - Distractions and external noise
Students in the theatre should be isolated from external events. Fixed double-glazing would keep out sounds and clerestory glazing would hide external activities from view. Internally, noise associated with building services, such as flickering lights and air conditioning, is a possible cause of distraction. Traffic to and from the room is a common cause of distraction, but is perhaps beyond the designers' control.

9 - Appropriate size and rake
The ability of students at the back of the theatre to read what is projected at the front needs to be considered. The maximum room depth should be around 20 m, or 18 rows. Screen width also dictates room depth – viewing distance should be between two and six times screen width. Room width is governed by viewing angle (40° maximum), speech projection angles (90° maximum) and egress limits on the number of seats in a row (22 maximum with gangways at each end). A stepped rake of 150 mm per row is suggested. This equates to a 1:6 ramp, far too steep for aisle wheelchair access. Room for wheelchairs could be provided at the rear or front of the theatre.

10 - Internal finishes
Though ranked low by students and FMs in terms of their affect on learning, internal finishes are important as they affect other important criteria, such as internal acoustic quality and illumination.

11 - Shape of the room
Some theatre plans and sections are awkward in terms of access, egress, acoustics and sightlines. For example, parallel side walls may produce flutter echoes (unless diffusive or absorbent), but walls splayed at 25° (maximum) will add to sound reinforcement.