Dear all
Let’s delve into the crucial aspects of maintaining accurate tactile signs, including thickness, character size, style, color contrast, and the geometry of Braille elements:
1. Thickness:
• Why It Matters: The thickness of tactile signs impacts their durability and readability. Signs that are too thin may warp or break easily, ( if Acrylic is used), while overly thick signs can appear bulky and obstructive and may slide down or fall due to weight if not fixed or mounted properly.
• Well proven thickness would be 3mm for Acrylic base.
• Hence it is better to use High impact modified acrylic, specially formulated laminates, excellently engineered products like Rowmark, Gemini, IPI or P-mark of GGK. If this HIMA sheets are used, even 1.6 mm is enough. These materials are opaque and surface finish is non glare and has advantage of self dual color engraving.
• Ideal Thickness: Tactile signs should have a thickness of approximately 1/32 inch (0.8 mm). This ensures they are sturdy enough to withstand wear and tear without being overly prominent.
2. Character Size:
• Importance: Proper character size ensures readability for both sighted and visually impaired individuals.
• Braille Characters: Braille dots should have a diameter of 0.059 inches (1.5 mm). Convex in nature. This standard size allows users to distinguish individual dots by touch.
• Raised Characters: Raised characters (such as letters and numbers) should be at least 5/8 inch (16 mm) in height. Larger characters enhance visibility and readability.
3. Style and Font:
• Sans Serif Fonts: Use sans serif fonts (e.g., Arial, Helvetica) for raised characters. These fonts lack decorative flourishes, making them easier to recognize.
• Clear and Simple: Opt for clear, simple letterforms. Avoid overly ornate or intricate styles that may confuse users.
4. Color Contrast:
• High Contrast: Ensure a strong contrast between the background and raised characters. High contrast improves readability.
• Color Combinations: Dark characters on a light background or vice versa work well. For example:
• Black characters on a white background.
• White characters on a dark blue background.
• Avoid Low Contrast: Low contrast strains the eyes and hinders readability.
5. Geometry of Braille Elements:
• Braille Cells: Each Braille character consists of a 2x3 grid of dots (referred to as a Braille cell).
• Dot Placement:
• The dots are arranged in two columns, with three dots in each column.
• Left first column dots are 1,2and3.
• Right column is 4,5 and 6
• Otherwise arranged in three rows
• The top row contains dots 1, 4
• The middle row is 2 and 5,
• The bottom row is 3 and 6.
• Spacing: The distance between adjacent Braille cells should be at least 3/8 inch (9.5 mm) to prevent accidental overlap.
Very Important:
It is very important to have Tactile Raised Letters in accordance with the guidelines in all “CAPITALS “ to be followed by Braille Script in Grade1 in India,Australia, and more whereas GRADE2 should. be for USA. Remember, accurate tactile signs are essential for creating an inclusive environment. By adhering to these guidelines, we ensure that everyone can access critical information independently.
Written and published by
GGK
REF:
1. Harmonized Guidelines
2. ADA GUIDELINES.
3. Check with CONSULTANTS