The function and demands on Unisto Security Seals

The risk of theft and criminal energy grows with the value of goods being transported and the demands on Security Seals increase in turn. The following points influence our policy of designing high quality Security Seals: 

  • Security seals should indicate whether a locking device has already been opened
  • Tamper resistance by making manipulation nearly impossible, more difficult or at least time-consuming 
  • Adding tamper-evident features to visualise unauthorized manipulation on the security seal 
  • Resistance to substitution of component parts 
  • Avoid accidental breaking of the seal in situ 

These demands lead, as a rule, to the use of seals made from a variety of components and materials. In conjunction with the customer logo, consecutive numbering, barcode, data matrix codes etc. ensures that each seal is unique and cannot be substituted. 

Why should you avoid buying security seals from online portals?

Why do you seal containers such as shipping containers, duty free trolleys, drums etc.?

To protect your valuable content in those containers of course. You should therefore endeavour to use the best possible security seals. We believe that this is only achievable with expert advice.

It’s possible nowadays to buy security seals from various online portals, such as Ebay. But do you know who you are buying from? The integrity of the source is not guaranteed, and you cannot be sure that the seal you are buying is unique. You are buying completely anonymously. Because they can be easily manipulated, these kinds of seals are often bought for criminal purposes.

Good partnerships require trust and confidence.

Because of this, very little speaks in favour of buying security seals from online portals. Here are just a few arguments against it: 

  • The uniqueness of the seal is not guaranteed (number/barcode, colour, logo)
  • The traceability of the seal is not guaranteed
  • What would happen if you had an urgent problem with the seal? If there are any problems, you have no contact person or aftercare following your purchase
  • The relevant certificates are not available (ISO 17712, environmental, REACH etc.)
  • Long-term supply capability is not assured
  • Without advice, how you can make sure that you have chosen the best solution for your needs?
  • As you do not know the origin of the seal, the risk of fraud is very high.  Unfortunately, criminal origins cannot be ruled out

Our experience becomes your security

With Unisto, you are in good hands: you benefit from over 90 years' experience in the production of security seals and receive professional on-site advice from our security experts. You can enjoy the world's highest standards of quality, reliability and advice after delivery.

No online portal can guarantee so many advantages and reliability.

Get in touch and put us to the test. We’re looking forward to hearing from you!  

Seal Classification Overview

Indicative Security Seal 
Seal that is designed and manufactured of material that can easily be broken by hand or by using a simple snipping tool or shears. 

Security Seal 
Seal that is designed and manufactured of material that provides limited resistance to unauthorized access and requires lightweight tool for removal.

High Security Seals  
Seal that is designed and manufactured of material such as metal or metal cable with the purpose to delay intrusion. High security seals generally must be removed with heavy bolt cutters or cable cutters. 

The physical strength of the seals is determined by a Tensile, Shear, Bending, and Impact Test. 

Mechanical tests – for the classification of security seals, the following must be tested: 

  • a) Impact test: 
    To determine impact resilience at 18 °C and -27 °C, an impact test must be carried out.  The impact test takes place in three phases. In each phase, a defined force must be exerted on the seal five times (15 times in total). 
  • b) Pull test: 
    To test the strength of the closure mechanism of a seal, a pull test must be carried out. 
  • c) Bend test 
    To determine the resilience of a seal under a bending load, the bending test must be carried out (to determine the strength required to bend the seal by 90° within 3 seconds). 
  • d) Shear test: 
    To test the resilience of a seal to slicing with a cutting blade, such as bolt cutters, a shear test must be carried out. 

Important: All Security seals must be checked to indicate all sorts of manipulation. 

Types of Security Seal

Plastic security seals   

Plastic seals are manufactured using different types of plastic material and are mainly used as an indicator of tampering or unauthorised entry. The design of the plastic seals allows a visual detection, whether a manipulation attempt or a theft has taken place. As a broken plastic security seal indicates tampering, they are frequently referred to as indicative seals.

There are different categories of plastic security seals but they are mainly designed as adjustable length seals (also called variable length seals or pull-tight seals), fix-length seals, padlock seals or tote box seals. Depending on the application, type of container that should be sealed and requirements on the security level, a type of plastic seal is better for the purpose as the others. Typical applications are, for example, bags, trolleys for the airline and catering sector, boxes, drums, roll cages, etc.

Usually the plastic security seals can be customized with a customer logo and their uniqueness is guaranteed thanks to the unique numbering and barcode. 

The different colours available for the plastic security seals allow not only a personalization of the seal but also may ease the customer’s logistic processes. 

Security Seal made of metal 

  • Metal band /Metal Clip seals  
    manufactured from a metal material are generally used to provide barrier protection. 
  • Bolt seals   
    offer the highest level of barrier protection and are manufactured in two metal parts that are designed to fit together via a locking mechanism. 
  • Cable seals 
    consist of a steel cable which is fixed at one end into the locking mechanism of the seal body.  

Re-usable Security Seals 
Re-usable seals consist of a main re-usable body which can be sealed with a single use seal.  

Electronic seals  
Electronic seals are typically reusable. Generate a unique time, date and number each time the seal is closed and opened. Register and record all sealing and opening events. 

Tamper Evident Labels  
Tamper Evident labels can be physically stuck to a surface and give the user the option of leaving a residue, disintegrating, and/or displaying an indication of attempted removal or tampering. 

Choosing the right Security Seal for the job

Since many factors play a decisive role in determining the right security seal for the job, we believe that only expert advice from our security seal specialists can lead to the ideal security seal being chosen for a specific application. 

The following factors determine the choice of the appropriate seal for a particular role: 

  • What type of unit needs to be sealed? For example: trucks, containers, cash boxes, utility meters, kegs, sacks, trolleys, doors, boxes, cases, caskets, pouches, etc. 
  • Under what ambient temperature conditions will the seals be used? 
  • How long will the security seal be fixed on the sealed unit? 
  • Are you looking for an easy removable seal or a barrier seal? 
  • For how long will the sealed unit be left unsupervised? 
  • How valuable are contents? 
  • Which type of number system is required for the application (sequential or random)? 
  • Must the serial number be electronically readable? Which type of barcode?
  • What are the logistical requirements? (are various colours required?) 

Our experienced Security team provide expert advice to suit your individual applications and requirements. 

Elements of an Effective Seal Program and Areas of Responsibility

Seal Manufacturers Responsibility 

  • Producing and shipping high quality Security Seals 
  • To guarantee physical strength and integrity of the Security seal 
  • To ensure unique marking and numbering 
  • Provide Tamper resistance and tamper evidence solutions 
  • Good Security practices before application - ISO 17712:2013 – annex A - Seal Manufacturers' Security-Related Practices 
  • Advice customers finding proper selection of the Security seal solution to fit to specific customer needs 

Customer and security seal user Responsibility 

  • Inspect your seals on receipt (type, colour, marking, numbers – did you get what you ordered?) 
  • Store the seals at a proper place 
  • Make sure that only authorized people have access to your warehouse resp. the security seals 
  • Document the seals given to the users 
  • Train the users about the features and the use of the seal 
  • Train the user how to proper seal 
  • Educate people to watch for evidence of tampering 
  • Document that the seal was properly locked and intact after applying 
  • Check integrity and number of the security seal before cutting or breaking it 
  • Any irregularity or damage on the security seal has to recorded (take pictures) 
  • If needed return such seals and application pictures to the seal manufacturer for inspection 

For further support or questions please contact one of our security seal experts.

Unisto is ISO 17712:2013 certified including Annex A - Seal Manufacturers’ security-related practices.