Class 4 Flammable Solid Sign

Hazardous Sign – Class 4 Flammable Solid Sign

Class 4 Flammable Solid Sign – The Class 4 Flammable Solid Sign is a valuable tool to help safeguard workers health and safety but is not a replacement for the security precautions needed to remove or mitigate hazards. The Flammable Solid Sign Class 4.1 pictogram has symbols easy to understand to quickly warn of hazards that could cause injury and accident. The Flammable Solid contains other materials that have been hydrated with water or gasoline that are not prone to the blast but can explode that burn; and substances directly delegated by the transport department to Division 4.1

What’s the difference between the striped version and the red border version?

• The striped diamond (Class 4.1 placard) is required for transport and bulk storage of flammable solids under the UN Dangerous Goods system. It must be used on vehicles, depots, and shipping containers (minimum 250 mm size for transport).

• The red border GHS pictogram is used for workplace and container labelling, such as bottles, drums, and lab cabinets, under NZ Hazardous Substances regulations.

👉 In short: Transport = striped placard, Workplace = red border GHS label.

Note on 120 mm size: The 120 mm option is not compliant for transport placards, as NZ regulations require a minimum of 250 mm per side for vehicle use. However, it is very useful for small-scale applications such as cylinder cages, storage cabinets, and indoor warning signage where space is limited.

Note on larger sizes (400 mm – 800 mm): While 250 mm is the minimum required size for transport placards, larger signs (400 mm, 600 mm, 800 mm) are recommended for warehouses, depots, bulk storage areas, and outdoor use. The extra size improves long-distance visibility and makes hazards clear to staff, visitors, and emergency responders.

“Before you spark up that reaction, see how Class 4 materials rate on our Dangerous Goods Class Guide. It’s solid advice.”

Classifications:

Properties of hazardous substances have been classified so to determine the best way the risks can be managed. They have been classified into eight key hazard classes:

•  1: Explosives.
•  2: Flammable gases.
•  3: Flammable liquids.
•  4: Flammable solids.
•  5: Oxidising substances.
•  6: Substances toxic to people.
•  8: Corrosive substances.
•  9: Substances toxic to the environment.

FAQ

1. What does a Class 4 Flammable Solid Sign mean?
   It identifies substances that can ignite easily through friction, heat, or contact with an ignition source. Examples include naphthalene, sulphur, and safety matches.

2. Where should Class 4 Flammable Solid Signs be used?
   They must be displayed on transport vehicles, depots, and storage areas handling flammable solids, in line with NZ and AU dangerous goods regulations.

3. What size Class 4 sign do I need?
   For transport, signs must be at least 250 mm per side. The 120 mm option is ideal for cabinets and indoor storage, while 400–800 mm sizes are recommended for warehouses and outdoor storage.

How to choose the right mounting options.

Corflute: short term less than 2 years outdoors

Thin PVC: Medium term, more than 2 years

ACM: Long term 5 years or more

Supplied as a sticker:

long term digital print laminated for long term use. With a life of 5 years or more. We use a Hi Tac vinyl which allows it to be applied most surfaces.

Magnetic mounting option for the Class 4 Flammable Solid Sign

Flexible, vehicle-grade magnetic placards with the Class 4 Flammable Solid Sign printed on premium vinyl, laminated, and mounted to automotive magnetic sheeting. They stick to ferrous steel panels and remove without residue—ideal for vehicles that only carry DG sometimes.

Who they’re for

• Contractors / couriers who transport Dangerous Goods occasionally

• Hire or multi-use vehicles (no permanent signage)

• Sites that swap classes depending on load (quick changeover)

• Size: 250 × 250 mm (meets common road minimums).

• Magnet: vehicle-grade sheet, 0.8–1.0 mm thick (30–40 mil), high-energy.

• Face film: outdoor self-adhesive vinyl + UV laminate (gloss).

• Operating temp: suitable from winter cold to summer heat (typical automotive range).

• Print: high-contrast black/white and red artwork.

Where they work (and don’t)

• Works on: painted steel panels that are flat, clean, and smooth.

• Doesn’t work on: aluminium, stainless, plastics, composites, heavy body filler; vinyl wraps, ceramic coatings, heavily textured paint.

• If customers have aluminium doors/ute trays, suggest self-adhesive or rigid ACM instead.

Fitment checklist

1. Clean & dry the panel (no wax/polish).

2. Warm, flat magnet—no curl.

3. Apply to flat steel only; press from centre out.

4. Do not bridge panel gaps, ribs or sharp curves.

5. Remove daily to clean/dry both surfaces; store flat.

6. In heavy rain/highway speeds, check edges haven’t lifted.

Care & maintenance

• Remove and wipe after wet weather; store flat (never rolled tight).

• Move position slightly each week to avoid differential fading.

• Avoid use on freshly resprayed paint (allow full cure).

Compliance note

• Magnet is a mounting method. The operator must ensure placards are the correct class, size, and securely affixed for the journey. Some carriers or site rules may require permanent/rigid placards—check your procedure.

For more information check out these links

• WorkSafe NZ – Hazardous Substances Management
  👉 WorkSafe NZ – Hazardous substances

• EPA NZ – HSNO Act guidance
  👉 EPA NZ – Hazardous Substances and New Organisms (HSNO) Act

• United Nations GHS
  👉 UN – Globally Harmonized System (GHS)  

• Why you need the correct Hazard sign

Check out our: Complete Guide to Dangerous Goods Placards (NZ & AU)

Why you need the correct Hazard sign

NZS/AS 1319:1994 advocates simplicity and clarity in safety signage. To be effective, they should be easy to read and interpret at a glance.

The Standard is about the use of legible text and appropriate, simple symbols.

By simplifying the message, it reduces the risk of misinterpretation, which increases the chances of the sign’s warning or instruction being followed.

Enhancing the signs visibility through placement and colour

Placement and visibility will play a crucial role in the efficiency of safety signs.

The standard states that signs must be positioned near the hazard they are warning about, which ensures that the safety message is relevant. Also it advocates the use of contrasting colours for the background and lettering. This attention to the colour scheme will increase visibility and readability from a reasonable distance, which ensures the message is accessible.

The mission of Hazard Signs NZ is to provide quality-made safety signs to all of New Zealand. Our great prices and convenient online ordering platform make us a preferred supplier to many NZ businesses. All our signs are designed and manufactured in Invercargill to meet the workplace health and safety needs of all businesses and industries in New Zealand.

Please note. We make some of our safety signs to order and it may take 5 to 10 business days to receive. If you require your order urgently, please don’t hesitate to contact us to confirm an estimated delivery date prior to placing your order.

If you are not sure about what sign you need for your business, just contact us at +6432183350 or email us and we will make it ready for you.