OSH Signage Standards

According to the Department of Labor and Employment (DOLE) Department Order No. 198-18, the NFPA (National Fire Protection Association), and the Bureau of Fire Protection (BFP), safety signs must follow standard color codes, shapes, and sizes to be effective and recognizable across industries.

Let’s explore what each color and symbol means and how to use them correctly in your workplace.

Why Safety Signs and Color Codes Are Important?

Every workplace contains hazards and some visible, others hidden. Safety signs act as visual communication tools that alert workers to these dangers, guide them toward safety equipment, and indicate emergency routes.

When properly implemented, they help:

• Reduce workplace injuries and property damage

• Promote hazard awareness and safety culture

• Ensure compliance with DOLE, BFP, and fire safety regulations

• Improve response time during emergencies

Standard Safety Color Codes (Based on DOLE, NFPA 704, and BFP Guidelines)

Color coding is essential for quick recognition of hazards and safety information. The following are the standard safety colors recognized by DOLE, NFPA, and BFP:

• Red

  • Meaning / Use: Indicates danger, prohibition, or fire equipment.

  • Examples: Fire extinguishers, stop buttons, “No Smoking” signs.

  • Standard Code Reference: NFPA 10 / DOLE OSH Standards Rule 1080 / BFP Fire Code.

• Yellow

  • Meaning / Use: Signals caution or a warning against potential hazards.

  • Examples: “Caution: Wet Floor,” “High Voltage.”

  • Standard Code Reference: DOLE Rule 1080 - Color Coding for Hazards.

• Green

  • Meaning / Use: Denotes safety, first aid, or emergency exits.

  • Examples: First aid kits, emergency showers, exit signs.

  • Standard Code Reference: DOLE Rule 1080 / ISO 3864-1.

• Blue

  • Meaning / Use: Represents mandatory actions or required PPE (Personal Protective Equipment).

  • Examples: “Wear Helmet,” “Hearing Protection Required.”

  • Standard Code Reference: DOLE Rule 1080 / ISO 3864-2.

•  Black / White

  • Meaning / Use: Used for directional or informational markings.

  • Examples: Floor lines, area boundaries, traffic arrows.

  • Standard Code Reference: DOLE Rule 1080 Section 1083.03(b).

Standard Safety Sign Sizes (DOLE / NFPA / ISO Guidelines)

Safety signs must be visible, clear, and readable from a safe distance. According to DOLE Rule 1083.03(b) and ISO 3864-1, the following are the recommended minimum dimensions based on viewing distance:

• For 1 to 5 meters viewing distance:

  • Minimum Sign Size: 200 x 200 mm

  • Minimum Letter Height: 20 mm

• For 5 to 10 meters viewing distance:

  • Minimum Sign Size: 400 x 400 mm

  • Minimum Letter Height: 40 mm

• For 10 to 20 meters viewing distance:

  • Minimum Sign Size: 600 x 600 mm

  • Minimum Letter Height: 60 mm

• For 20 meters and above viewing distance:

  • Minimum Sign Size: 800 x 800 mm

  • Minimum Letter Height: 80 mm

Tip: Signs should be made of durable, reflective, and weather-resistant materials. According to BFP Fire Code of the Philippines, fire exit and evacuation signs must remain visible even during power failures (using photoluminescent or illuminated materials).

Categories of Safety Signs and Their Standard Designs

1. Prohibition Signs

• Shape: Circular

  1. Color: Red border, white background, black symbol

  2. Meaning: Indicates actions that are not allowed.

  3. Examples: No smoking, no entry, no mobile phones

2. Warning Signs

• Shape: Equilateral triangle

• Color: Yellow background, black border, black symbol

• Meaning: Warns about potential hazards.

• Examples: Slippery floor, flammable materials, high voltage

3. Mandatory Signs

• Shape: Circular

• Color: Blue background, white symbol

• Meaning: Specifies required safety actions or PPE.

• Examples: Wear gloves, helmet required, face shield must be worn

4. Emergency Information Signs

• Shape: Rectangle or square

• Color: Green background, white symbol or text

• Meaning: Indicates safe conditions or locations of emergency equipment.

• Examples: Emergency exit, first aid station, safety shower

5. Fire Safety Signs

• Shape: Rectangle or square

• Color: Red background, white symbol

• Meaning: Shows locations of fire-fighting equipment.

• Examples: Fire extinguisher, fire hose, fire alarm, fire exit

NFPA Diamond (Fire Hazard Identification System)

The NFPA 704 “Fire Diamond” is a color-coded labeling system developed by the National Fire Protection Association (NFPA). It helps workers and emergency responders quickly identify the health, flammability, and reactivity hazards of chemicals and materials.

Each color on the diamond represents a specific type of risk:

• Blue – Health Hazard

  • Indicates the potential danger a substance poses to health.

  • Rating Scale (0–4):

    • 0 – No hazard

    • 4 – Severe or deadly hazard

• Red – Flammability

  • Refers to the material’s ability to catch fire or burn.

  • Rating Scale (0–4):

    • 0 – Will not burn

    • 4 – Highly flammable

• Yellow – Reactivity (Instability)

  • Shows the potential for a substance to react violently or explode under certain conditions.

  • Rating Scale (0–4):

    • 0 – Stable

    • 4 – May detonate or explode

• White – Special Information

  • Used for special hazard symbols or warnings such as:

    • OX – Oxidizer

    • ACID – Acidic material

    • ALK – Alkaline material

    • W – Reacts dangerously with water

Example: A label showing 3 in Red, 2 in Blue, 0 in Yellow means the substance is highly flammable, moderately harmful to health, and stable under normal conditions.

Best Practices for Using Safety Signs

1. Follow DOLE and BFP Standards: Always use compliant designs, symbols, and materials.

2. Install at Eye Level: Place signs where workers can easily see and interpret them.

3. Use Reflective or Illuminated Signs: Especially for fire exits and evacuation routes (required by BFP).

4. Inspect and Maintain Regularly: Replace faded or damaged signs immediately.

5. Include in Safety Orientation: Train new employees to recognize and understand all safety signs and color codes.

Quick Safety Tip

Even the most advanced safety system is only effective when workers understand what it means. Regular training and visual reminders can save lives.

Conclusion

Safety signs and color codes are universal tools of protection. They help workers identify risks, find safety equipment, and respond quickly during emergencies.

By following the standards set by DOLE Department Order 198-18, BFP Fire Code, and NFPA 704, every organization can build a safer, more compliant, and more efficient workplace.

Remember: safety awareness begins with visibility. Keep your signs clear, consistent, and compliant.