1988 Letter Series

Lower case letters are provided for series B, C, D, E, and EM.

Series EM lower case letters were created from the following document:

Standard Alphabets For Highway Signs and Pavement Markings

U.S. Department of Transportation

Federal Highway Administration, 1982

No universally accepted standard exists for lower case letters for series B, C, D, and E. However, in response to user requests, these lower case series were created by Transoft Solutions and are now included for use with GuideSIGN.

Note: The lower case letters for series B, C, D, and E are not standard and should be used with this in mind.

Method For Creating Lower Case Series

Lower case letters for series E were created by reducing the stroke width of the series EM lower case letters. Letter widths and spacings are identical with series EM.

In creating lower case letters for series B, C, and D, the assumption was made that the widths of lower case letters should reduce in the same ratio as the upper case letters.

Widths for lower case series B, C, and D were derived by reducing the width of series EM lower case letters by the average of all the widths of the upper case letters for each series divided by the average of all the widths of the upper case series EM letters. The letters ’r;i’ and ’r;l’ were ignored in calculating the average width.

Spacings for lower case series B, C, and D letters were derived by reducing the spacing for the series EM lower case letters by the average of the spacing factors for the upper case letters for each series divided by the average of the spacing factors for the upper case series EM letters.

Stroke widths for lower case series B, C, and D letters were derived by reducing the stroke width of the series EM lower case letters by the stroke width of the upper case letters of each series divided by the stroke width of the upper case series EM letters.

Lower Case Series Width and Spacing Factors

	F	EM	E	D	C	B
Width Factor	1.1	1.0	1.0	0.84	0.68	0.54
Spacing Factor	1.1	1.0	1.0	0.91	0.82	0.72

2003 Letter Series

The 2003 letter series drawings were based on the following publication:

Standard Alphabets For Traffic Control Devices

Is a part of the Standard Highway Signs book - 2004 Edition

Prepared by the Federal Highway Administration

GuideSIGN’s letters were drawn at a nominal height of 200 mm. The FHWA Series 2000 Edition Font Spacing Table values were multiplied by a factor of 2 to derive letter widths (the FHWA letter widths are based on 100 mm upper case letter heights).The lower case letter height is 146 mm above the baseline. The height of the round (or loop) lower case letter height is 150 mm above the baseline. Every effort was made to maintain the spirit of the letter examples provided by the FHWA shapes while providing consistently drawn letters. The following tables list the amounts 'over' and 'under' the nominal 200 mm upper case letter heights used to draw the letters.

Uppercase Letter Dimension Criteria

	F	EM	E	D	C	B
Over	3.3	2.8	3.5	3.5	3.5	2.8
Nominal	200	200	200	200	200	200
Under	3.4	3.5	3.5	3.5	3.5	3.5
Total Height	206.7	206.3	207	207	207	207

Lowercase Letter Dimension Criteria

	F	EM	E	D	C	B
Over	3.3	3.5	3.5	3.5	3.5	3.5
Nominal	200	200	200	200	200	200
Under	3.4	4	4	4	4	4
Total Height	206.7	207.5	207.5	207.5	207.5	207.5

Numeral Dimension Criteria

	F	EM	E	D	C	B
Over	3.3	3.5	3.5	3.5	3.5	3.5
Nominal	200	200	200	200	200	200
Under	3.4	3.5	3.5	3.5	3.5	3.5
Total Height	206.7	207	207	207	207	207

The following letters are noted exceptions to the widths specified in the FHWA spacing tables:

• Series B ampersand (&) was drawn to a width of 140 mm (at 200 mm nominal height) because this was the approximate width of the FHWA drawn letter and seemed more consistent with the letter series.
• Series B lower case ’g’ was drawn to a width of 74 mm (at 200 mm nominal height) to conform to the similar loop letters ’b’, ’d’, ’p’, and ’q’ in the B series. The lower case ’g’ conforms to its similar loop letters in all other letter series.
• Series C ampersand (&) was drawn to a width of 174 mm (at 200 mm nominal height) because this was the approximate width of the FHWA drawn letter and seemed more consistent with the letter series.
• Series D equal (=) was drawn to a width of 130 mm (at 200 mm nominal height) to be consistent with the C, E, and Em series characters. The left and right spacing was changed to 6 mm (at 200 mm nominal height).
• Series D plus (+) was drawn to a width of 130mm (at 200 mm nominal height) to be consistent with the C, E, and Em series.
• Series D quotes (“) was drawn to a width of 96 mm (at 200 mm nominal height) because this was the approximate width of the FHWA drawn letter - the value in the FHWA table was 36 mm (at 200 mm nominal height) which appeared to be incorrect. The left and right spacing was changed to 24 mm (at 200 mm nominal height).