|P.O. ENGINEERING DEPT.
Issue 7, 18.4.67
CLOCKS FOR PUBLIC OFFICES
This Instruction details special requirements relating to installations of clocks in public offices.
2. Types of clock provided
The clock system provided should be chosen in accordance with the principles laid down in B 3001. Wherever possible standard clocks should be employed but where this is unreasonable the procedure described in B 3005 should be followed. The standard clocks are:-
- Clocks Nos. 84A, 84B for installation on house style panels
- Clocks Nos. 86A, 86B for installation in public office windows
- Clocks Nos. 74A, 76A, 78A, 80A, 82A, 74B, 76B, 78B, 82B used normally.
The cases of all clocks except Nos. 84A, 84B may be refinished by the architect to meet his colour scheme.
The position of all clocks should be agreed with the architect subject to the requirements of B 3001, and the following requirements for clocks mounted on public office windows:-
An electrical clock should be double-faced for preference, partly because the appearance of a plain back is not attractive. If the window faces in a direction towards the sun and is not completely shadowed by buildings, etc., across the street, it may be difficult to read the clock from within the office. If these
conditions apply, at least one other single-dial clock should be installed on a wall. To enable an assessment of the shielding effect of other buildings to be made, the maximum elevation of the sun at a number of places in the British Isles in various latitudes is given in Table 1 for windows facing different directions. These directions are true and not magnetic.
MAXIMUM ELEVATION OF THE SUN
||Direction - ESE
||Direction - SE
||Direction - SSE
||Direction - S
The distance between the window and the clock face should be as small as possible but not less than 4 in.
Clock wiring in public offices should be concealed.