Sign selection
|
# Pictograms Sign types Sign size & viewing distances #Pictograms The standard BS ISO 3864-1:2011 (that has superseded BS 5499-1:2002) specifies a system of geometric shapes and safety colours for use with the appropriate graphical symbols to produce safety signs. It is applicable to signs that provide information on the actions to be taken to prevent or reduce the risk of accidents, warn of the presence of a potential hazard and for dealing with certain emergencies including the identification of escape routes and the location of fire equipment. The general meanings assigned to geometric shapes, safety colours and contrast colours can be found in the table below :
#Sign types For signs to be seen clearly they must be mounted according to the appropriate viewing angle. Type 1 (single-sided)  Type 2 (double-sided) A Type 2 sign is mounted perpendicularly to the wall by means of either a rigid aluminium or flexible plastic bracket. The flexible bracket consists of a plastic strip which enables the perpendicular installation of a double-sided Type 2 sign and was developed with the aim of allowing a sign to swing through a 180 radius without breaking if struck.  Type 3 (double-sided) A Type 3 suspended double-sided sign is intended to be suspended from a ceiling. The sign is supplied with fixing holes drilled in the top corners to allow the appropriate suspension fixing to be attached. (fixings not supplied)  Type P (panoramic signs) A panoramic sign offers the greatest visibility and is printed on the two outfacing surfaces to offer a 180 view radius.  #Sign size and viewing distances The size of the sign is defined by the maximum viewing distance from which the sign is understandable. The table below shows the maximum viewing distance of each sign according to BS 5499-4:2013 for safe condition signs and BS ISO 3864-1:2011 (superceding BS 5499-1:2002) for other signs categories. The viewing distance at which a sign of a particular size is conspicuous and comprehensible depends on the illumination of the sign and the amount of detail it contains.  D - maximum viewing distance (mm) h - overall height (printed area) of the signboard (mm). Z - distance factor taking into account the sign category, illlumination factors and level of detail. According to BS 5499-4:2013 – escape route signs have a distance factor value (Z) of 170 whereas other sign types have an assumed distance factor value of 60 as defined by BS ISO 3864-1:2011.
The size of the sign is chosen according to the maximum viewing distance and the layout of the premises. However, the viewing distance at which a sign of a particular size is conspicuous and comprehensible depends on the sign category, illumination factors and level of detail. Viewing distances (according to BS ISO 3864-1: 2011) – Fire equipment and sign categories Viewing distances (according to BS 5499-4: 2013) – Escape route signs  |
