{"id":6697,"date":"2023-10-29T13:27:49","date_gmt":"2023-10-29T13:27:49","guid":{"rendered":"https:\/\/pts-vietnam.com\/?p=6697"},"modified":"2026-10-10T03:42:04","modified_gmt":"2026-10-10T03:42:04","slug":"carton-box-symbols-meaning","status":"publish","type":"post","link":"https:\/\/pts-vietnam.com\/en\/carton-box-symbols-meaning\/","title":{"rendered":"Carton Box Symbols: Meanings and How to Print Them Correctly"},"content":{"rendered":"\n

Carton box symbols fall into three groups. The first is handling and storage symbols according to ISO 780. The second is environmental and recycling symbols. The third is technical information about the box, such as the box maker’s certificate and strength ratings.<\/p>\n\n\n\n

This article explains the meaning of the symbols on corrugated boxes for buyers, box designers and box printing plants. The final section describes how to print the symbols directly on the production line.<\/p>\n\n\n

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\"Handling
Handling symbols printed on a corrugated carton<\/figcaption><\/figure>\n<\/div>\n\n\n

Handling and Storage Symbols (ISO 780)<\/h2>\n\n\n\n

ISO 780 specifies a set of graphical symbols for transport packaging. The symbols let handlers understand the requirements without reading any text. The standard does not cover specific instructions for dangerous goods.<\/p>\n\n\n\n

Fragile<\/h3>\n\n\n
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\"Fragile
Fragile symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a stemmed wine glass. It indicates that the contents are easily damaged by impact. Handlers should lift and set the box down gently, never throw it and never let it drop.<\/p>\n\n\n\n

This way up<\/h3>\n\n\n
\n
\"This
This way up symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows two parallel arrows pointing upwards with a horizontal bar at the base. It indicates the correct upright position of the box. The box must not be turned upside down or laid on its side.<\/p>\n\n\n\n

Keep dry<\/h3>\n\n\n
\n
\"Keep
Keep dry symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows an umbrella with raindrops falling on it. Both the goods and the corrugated box can be damaged by moisture. The box must be protected when handled outdoors.<\/p>\n\n\n\n

Keep away from sunlight<\/h3>\n\n\n
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\"Keep
Keep away from sunlight symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a sun with rays and a shelter above it. It requires that the box is not exposed to direct sunlight.<\/p>\n\n\n\n

Temperature limits<\/h3>\n\n\n
\n
\"Temperature
Temperature limits symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a thermometer with the minimum and maximum temperature values. The goods may only be stored and transported within the temperature range stated on the symbol.<\/p>\n\n\n\n

Carriers should check the temperature range before loading. Such goods usually require a refrigerated truck or a temperature-controlled warehouse.<\/p>\n\n\n\n

Centre of gravity<\/h3>\n\n\n
\n
\"Centre
Centre of gravity symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a circle divided into four quarters, with two opposite quarters filled in. It marks the position of the centre of gravity when it is offset from the geometric centre of the box.<\/p>\n\n\n\n

When lifting with a forklift or crane, the forks and slings must be positioned evenly around this point. If it is ignored, the package may tilt, tip over or slide off the forks.<\/p>\n\n\n\n

Stacking limit by mass<\/h3>\n\n\n
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\"Stacking
Stacking limit by mass symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a weight placed on a box, with the maximum mass in kg. This is the maximum total mass that may be placed on top of the bottom box.<\/p>\n\n\n\n

Stacking limit by number<\/h3>\n\n\n
\n
\"Stacking
Stacking limit by number symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows stacked boxes with the number “n”. The number indicates the maximum number of identical boxes that may be stacked on top of the bottom box. The bottom box is not included in this number.<\/p>\n\n\n\n

Do not stack<\/h3>\n\n\n
\n
\"Do
Do not stack symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a box with a load on top, crossed out. No box or object of any kind may be placed on top.<\/p>\n\n\n\n

Clamp as indicated<\/h3>\n\n\n
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\"Clamp
Clamp as indicated symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows two clamp arms pressing against two opposite sides of the box. It is printed on the two sides where forklift clamps may make contact.<\/p>\n\n\n\n

Do not clamp as indicated<\/h3>\n\n\n
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\"Do
Do not clamp as indicated symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol is the same as the clamp symbol but crossed out. The two sides bearing this symbol must not be used as clamping surfaces.<\/p>\n\n\n\n

Use no hooks<\/h3>\n\n\n
\n
\"Use
Use no hooks symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a crossed-out hook. Hand hooks must not be used to pull or lift the box.<\/p>\n\n\n\n

Do not roll<\/h3>\n\n\n
\n
\"Do
Do not roll symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a box tumbling over its edges, crossed out. The box must not be rolled or tipped over to move it.<\/p>\n\n\n\n

Do not use hand truck here<\/h3>\n\n\n
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\"Do
Do not use hand truck here symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a crossed-out hand truck. The blade of a hand truck must not be inserted on the side bearing the symbol.<\/p>\n\n\n\n

Use no forklift<\/h3>\n\n\n\n

The symbol shows a crossed-out forklift. The side bearing the symbol must not be used for inserting forklift forks.<\/p>\n\n\n\n

Sling here<\/h3>\n\n\n
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\"Sling
Sling here symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows a length of chain. It indicates where slings should be placed when lifting the package with a crane.<\/p>\n\n\n\n

Magnetic sensitive<\/h3>\n\n\n
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\"Magnetic
Magnetic sensitive warning symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

This symbol is not part of the ISO 780 set. Some shippers print it themselves to warn that the goods are sensitive to magnetic fields, such as electronic equipment or measuring instruments. The goods should be kept away from magnets and large electric motors.<\/p>\n\n\n\n

Environmental and Recycling Symbols<\/h2>\n\n\n\n

Mobius loop<\/h3>\n\n\n
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\"Mobius
Mobius loop recyclable symbol<\/figcaption><\/figure>\n<\/div>\n\n\n

The symbol shows three twisted arrows forming a triangular loop. It indicates that the packaging is made from recyclable material. It does not mean that the box already contains recycled material. Nor does it mean that the box is intended for reuse.<\/p>\n\n\n\n

Mobius loop with percentage<\/h3>\n\n\n\n

When a percentage figure appears in the middle or next to it, the symbol indicates the proportion of recycled material in the packaging. Only the version with a percentage confirms that the packaging contains recycled material.<\/p>\n\n\n\n

FSC<\/h3>\n\n\n\n

The FSC logo, a tree combined with a check mark, indicates that the paper used for the box comes from responsibly managed wood or paper sources. Only FSC-certified companies may print this logo, together with their certificate code.<\/p>\n\n\n\n

PAP 20, PAP 21, PAP 22<\/h3>\n\n\n\n

The code consists of the letters PAP and a number, usually printed inside a loop of arrows. The coding system is set out in European Commission Decision 97\/129\/EC. PAP 20 is corrugated board, PAP 21 is non-corrugated board and PAP 22 is paper.<\/p>\n\n\n\n

Technical Information on the Box<\/h2>\n\n\n\n

Box Maker’s Certificate<\/h3>\n\n\n\n

This is a round stamp, usually printed on the bottom of the box. It is common on goods exported to the United States, under NMFC Item 222 and UFC Rule 41. The stamp states the name and location of the box manufacturer and the strength ratings.<\/p>\n\n\n\n

There are two common versions. The Bursting Test version states the bursting strength and the minimum combined basis weight of the facings. The Edge Crush Test (ECT) version states the ECT value. Both versions state the size limit and the gross weight limit of the box.<\/p>\n\n\n\n

If a box exceeds the limits on the stamp, the carrier may refuse damage claims.<\/p>\n\n\n\n

Box Compression Test (BCT)<\/h3>\n\n\n\n

BCT is the maximum compressive load the complete box can withstand before it collapses. This value is directly related to the number of layers that can be stacked safely in a warehouse. BCT depends on the ECT of the corrugated board, the box perimeter and the box height.<\/p>\n\n\n\n

Humidity, storage time and pallet overhang all reduce BCT. The stacking limit printed on the box should therefore be calculated from BCT with a safety factor.<\/p>\n\n\n\n

The quality of the board produced by the corrugated line<\/a> has a direct effect on ECT and BCT.<\/p>\n\n\n\n

Other printed information<\/h3>\n\n\n\n

In addition to the packaging symbols, boxes usually carry the place of manufacture, product name, quantity, weight and dimensions. Export cargo also carries the package number, port of destination and order number.<\/p>\n\n\n\n

Dangerous Goods Labels and the Radiation Symbol<\/h2>\n\n\n\n

The three-bladed radiation symbol is not an ordinary packaging symbol. It is the Class 7 dangerous goods label, applied in accordance with the dangerous goods transport regulations for each mode of transport. Labels for flammable, corrosive or toxic substances also belong to this system.<\/p>\n\n\n\n

Printing Symbols on Corrugated Boxes in the Factory<\/h2>\n\n\n\n

Printing with a flexo printer<\/h3>\n\n\n\n

Fixed symbols such as Fragile, This way up and Keep dry are printed with a flexo printer<\/a> at the same time as the box. The symbols are placed on a separate printing plate or combined on the same plate with other content in the same colour.<\/p>\n\n\n\n

When designing the printing plate, note the following points:<\/p>\n\n\n\n