Standard Letters and Numerals of Different Heights for Use on Highway Signs
1968 Edition

The overview of IRC 30 details the prescribed forms of letters and numerals shown in Plates 1 and 2, with their component measurements listed in Tables 1 and 2 (Clause 2.1). Letter dimensions for multiple heights can be found in Table 1, while numeral dimensions are in Table 2. Spacing between adjacent characters is specified in Table 3. Minor adjustments to shapes or spacing are allowable within reasonable limits to accommodate manufacturing constraints (Clause 4.2). This ensures signs remain legible and manufacturable while adhering to standardization.

References: Clause 2.1, Clause 4.2, Tables 1-3, Plates 1 and 2

IRC 30 defines the standard letter and numeral shapes in Plates 1 and 2, with detailed dimensional data for sizes ranging from 5 cm to 30 cm provided in Tables 1 and 2 (Clauses 1.1 and 2.1). The code permits minor shape or spacing modifications within reasonable boundaries if manufacturing difficulties arise (Clause 4.2). Additionally, Table 3 specifies the spacing between characters. These standards promote uniformity for highway signage such as kilometre stones and route markers.

References: Clauses 1.1, 2.1, 4.2

The code provides standardized dimensions for letters with heights varying from 5 cm to 30 cm. Table 1 presents detailed component measurements for each letter size, and Table 3 outlines recommended spacing between letters. Minor shape or spacing adjustments are permissible if manufacturing constraints exist (Clause 4.2). Plate 1 illustrates the letter shapes, covering the height range mentioned (Clauses 1.1 and 2.1). Numerals have corresponding dimensions in Table 2 and spacing in Table 3. These specifications ensure consistent legibility on highway signs.

References: Clauses 1.1, 2.1, 4.2

Standard numeral dimensions for sizes between 5 cm and 30 cm are specified in Table 2, detailing the component measurements for each numeral as per IRC 30. These shapes and sizes maintain consistency on highway signage such as kilometre stones and route markers (Clauses 1.1 and 2.1). Minor alterations to numeral shapes or spacing can be made within reasonable limits if manufacturing challenges occur (Clause 4.2). Spacing details are provided in Table 3. This size range accommodates varied signage requirements.

References: Clauses 1.1, 2.1, 4.2

Spacing guidelines for adjacent letters and numerals are laid out in Table 3 of IRC 30. The code authorizes minor shape or spacing adjustments within reasonable limits to address manufacturing constraints (Clause 4.2). For precise letter and numeral sizes, refer to Tables 1 and 2 respectively. The standard shapes are depicted in Plates 1 and 2 (Clause 2.1). Exact spacing values should be taken from Table 3, allowing slight modifications if required for production.

References: Clause 4.2, Clause 2.1, Tables 1-3

The use of standard letters and numerals follows specific dimension and spacing requirements to guarantee readability and manufacturability as outlined in IRC 30. Plates 1 and 2 illustrate the standard shapes. Table 1 lists the letter sizes, Table 2 the numeral sizes, and Table 3 the spacing between characters. Minor permissible alterations to shape or spacing accommodate manufacturing needs without compromising clarity (Clause 4.2).

References: Clauses 2.1, 4.2, Tables 1-3

According to Clause 4.1 of IRC 30, it is advised that Public Works Departments and sign fabricators create templates out of light metal or other suitable materials for letters and numerals of varying sizes to assist in sign layout. Clause 4.2 allows minor modifications to shapes and spacing if manufacturing difficulties arise. Standard sizes range from 5 cm to 30 cm in height (Clause 1.1). For exact dimensions and spacing, Tables 1, 2, and 3 provide the necessary specifications.

References: Clauses 1.1, 4.1, 4.2

IRC 30 acknowledges manufacturing considerations by permitting minor adjustments to letter and numeral shapes or spacing within reasonable limits if incompatibilities with production methods arise (Clause 4.2). Dimensions for letters and numerals are detailed in Tables 1 and 2, with spacing in Table 3. Plates 1 and 2 show the standard forms. Clause 4.1 recommends that manufacturers develop templates of suitable materials for different sizes to streamline the sign layout process. These guidelines balance standardization with manufacturing practicality.

References: Clauses 2.1, 4.1, 4.2

IRC 30 provides the standardized forms and measurements for letters and numerals on highway signs including:

• Plates 1 and 2 presenting the letter and numeral shapes respectively (Clause 2.1).
• Table 1 detailing letter component dimensions for sizes between 5 cm and 30 cm.
• Table 2 outlining numeral dimensions for the same size range.
• Table 3 specifying spacing between adjacent characters.
• Allowance for minor shape or spacing modifications within reasonable limits if production constraints arise (Clause 4.2).

These references ensure consistent and legible highway signage throughout India (Clause 1.1).

Exact tables and plates are integral to sign design and manufacturing but are not included in this summary.

References: Clauses 1.1, 2.1, 4.2