Plastic Securty Seals
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What are plastic seals and why do they work?

Plastic seals are a versatile security seal that provide a tamper-evident solution for theft and interference. They are used across almost every major industry and for a variety of applications such as transport and logistics, emergency exits, fire extinguishers, medicine cabinets and utility meters. The effectiveness of their application may seem imprecise to the inexperienced eye but in this blog, we will highlight when it is optimal to use this seal type and where they may benefit your supply chain.

So what are plastic security seals?

Unlike heavy duty barrier seals, such as metal bolt seals or cable seals, plastic seals do not meet the ISO 17712 standard and therefore have no international security value. They are classified as ‘indicative; seals, as they provide a visual indicator that a item or area has been accessed without approval. These seals are intended for single use and they do not provide any tamper-proof features (unlike metal barrier seals).

On the surface, plastic security seals may be considered a luxury to ensuring adherance to company security procedures, however the statistics show the exact opposite. Whilst this simple security solution does not protect goods by its tensile strength or resistance, it provides a visual identifier written on the tag or head, usually consisting of numbering which is sequentially printed by each batch. If the applied seal no longer has the associated sequential number that was recorded at the time of sealing then it is clear that the contents are compromised and tampering has occurred.

Generally after use, plastic seals are disposable and fully recyclable due to the material used during their manufacturing (polypropelene). Plastic pull seal are often required for the transport of a bag or sack as well as for the inspection and testing measures for fire extinguishers (NF EN 3 standard), utility meters, safety valves and circuit breakers.

How do I apply and remove plastic seals?

Plastic seals are also referred to as ‘pull-tight seals’ due to their variable strap that can be threaded through the locking mechanism and pulled as tightly as required to fit the application. Once the seal has been pulled through the locking head, there is no turning back! The tail of the seal securely grips the lock and it will not be possible to to loosen or remove the seal without forcefully breaking it. We also provide plastic seals with double locking mechanisms such as the Heavy Duty Duaseal – 250mm, which allows the seal strap to be inserted into two separate locking heads for double the security.

However, there are several ways that plastic seals can be easily removed after their application (although not without making removal obvious!).

Our Anti-Tamper and Fire Extinguisher Seals has the lowest tensile strength of 6kg of tensile pressure. This allows these seals to be easily broken by hand when their removal is required. These seals are fully compliant with EN3 standard for extinguishers.

The Multipurpose Security Seal has a a moderate strength of 11kgs of pull in order to break the seal. It is not too easy to break by hand but these seals have a tear-off strip on the locking head which allows you to tear the strap from the head easily.

Our strongest plastic seal is the Heavy-Duty Multipurpose Security Seal. This plastic seal can withstand up to 25kg of force and the use of household cutting tools such as scissors will be necessary to remove the seal after application.

So when are plastic seals effective?

There are a number of benefits to using plastic security seals and produce consistent results across different sectors and usage. They are significantly used in airline cargo, roll-cages, bank and postal services, courier services, cash-in-transit, warehouses, bank bags, and cash boxes. There are many other uses too such as fire extinguishers, medical care, waste tracing, dining cars, logistical services, tote-boxes, and any application requiring complete security and theft prevention.

Transport & Logistics

Plastic tamper seals are commonly used within transport and logistics as a method of reducing access to sealed freighters, trucks and trailers. If you are an transport company and have inconsistencies with cargo, seals can provide a method to determine if tampering or theft has occurred. The plastic seal for the freight trailers act as a tamper-evident indicator that goods are being accessed before they have reached their destination. We offer Plastic Truck Seals (or Ring Seals) for a tamper-evident solution for transport and logistics, however high-security tamper-proof solutions are also available in our Barrier Seal range.

Anti-Tamper Fire Extinguisher Seals

Any company operating within a public or private premises must provide fire safety devices such as fire extinguishers which must be regularly checked to ensure conformity to the requirements of the EN-3 and safety regulations. Within EN-3 regulation, the safety requirements mentioned is the presence of seal that holds the pin of the extinguisher to prevent tampering and certify that the extinguisher cartridge is intact. The seal must therefore not be missing or broken during an inspection, otherwise it would be evidence of a breach.

Our Fire Inspection Tags are ideal for identifying and protecting fire extinguishers. They resist the traction exerted by the fire extinguisher but are easy to break in case of emergency thanks to their stems with balls or notches. In addition, they allow the extinguisher to be identified by its unique identification number and are available in a range of colours which can be alternated after each inspection.

Meter and Utility Seals

Plastic meter seals are also commonly used to secure electricity or water meters in companies and private homes to prevent Padlock Meter Sealsfraudulent activity on electricity or gas supply. Therefore, it is recommended to add a small indicative seal to provide tampering evidence and serve as a certificate of compliance for that meter.

Our Padlock Meter Seals have a serial numbered issued on the plastic locking head and once installed, they can only be removed in the presence of an inspector who will confirm the seal is intact and the numbering is correct. If removal of the seal is at any point required, the inspector can then apply a replacement seal and make a record of the new serial number for that meter.

Tamper-evident plastic security seals are one of the most effective security investments that any company can make to provide protection to assets. If you want to find out more about our product range or get a particular quote on our seals then please e-mail us at or call 01252 624305.

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