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Random Search Selectors - Frequently Asked Questions


There are many situations in which people, baggage, vehicles and other items need to be randomly selected to carry out thorough searches. But we are all susceptible to unconscious bias which makes it impossible to make truly random selections. In this post we answer many of the questions often asked about our Random Search Selectors and what they can do.

What is Random Search?

The Wikipedia definition of Random Search relates to numerical applications. But in this article we are covering the daily challenges faced by those who need to randomly select people, baggage, vehicles or other items, such as goods-in-transit, for search purposes.

People often ask: Can the police randomly search you?

In the UK the police have the power to stop and question you at any time. And, depending on the situation, they can search you. If they have reasonable grounds to suspect a person is carrying illegal drugs, a weapon, stolen property or something that can be used to commit a crime they can search them.

Another question that’s often asked is: Can an employer randomly search employees?

Employers are able to monitor their staff in several ways such as CCTV, drug testing, monitoring emails and online activity as well as bag or locker searches. Employers are required to have a written policy on searching their staff which should ensure privacy is always respected, searches are witnessed and conducted by a member of staff of the same sex. A Workplace Searches Policy should notify staff of the possibility of workplace searches and outline the specific areas subject to search.

The prospect of being randomly selected for a thorough search is a powerful deterrent. It can deter staff from pilfering and it can deter would-be smugglers. It can also deter people from concealing weapons or drugs so its a powerful crime-fighting tactic.

What is a Random Search Selector (RSS)?

It is simply impossible for humans to make truly random selections. We’ve previously covered the topic of selection bias and the need to make truly random selections for search purposes in a variety of situations.

Our Random Search Selector is a super-simple electronic device with an internal computer processor. The device uses a clever algorithm to calculate a truly random and unbiased “Search” or “Pass” indication each time the on board activation button is pressed, removing any potential for unconscious bias in the selection process.

Why Do You Need a Random Search Selector?

We live in an increasingly litigious society in which people are likely to initiate legal action and submit claims for compensation if they consider their treatment to have been unfair or biased. If someone thinks they have been selected due to their age, race, gender, religion, or other factors, they can possibly raise a valid complaint.

Random Search Selectors remove the potential for such complaints. These simple selection devices remove the responsibility for subject selection from those challenged with these tasks, ensuring every selection is truly random and avoiding the possibility of facing expensive legal action.

How Does a Random Search Selector Work?

The Random Search Selector is exceptionally simple to both setup and operate. The device features a large red button and prominent, LED illuminated ‘Pass’ or ‘Search’ indicator. In a practical application every person passing through a check point would press the big red button and the device randomly determines whether they should pass through or be selected for searching or further processing.

The percentage of people selected for searching is based on how the unit is configured. Internal dip switches are simply set to the percentage required from 0.5% up to 100%. This enables units to be setup to ensure throughput is maintained while ensuring those carrying out the searches are not overloaded.

dip switches
Random Search Selector Dip Switches - Set the Percentage

Since none of those passing through a check point knows whether the unit will randomly select them for searching or special processing this possibility acts as a powerful deterrent. Ensuring those who need to pass through check points are aware of the potential to be randomly chosen is an important aspect of the deterrence. This can be achieved using appropriate signage or, in workplace situations, via staff training, the staff handbook and internal communications.

What Random Search Selector Models and Options are Available?

Random Search Selectors are available as either mains powered or battery powered portable devices.

Mains powered Random Search Selectors are ideal for fixed, static installations where they are often used alongside metal detecting technology. Optional extras include both remote activation buttons and remote indicators.

Random Search Selector mains powered
Mains Powered Random Search Selector

Remote activation buttons can be conveniently located exactly where they are needed by those passing through a check point while the Random Search Selector unit is situated where the operator needs it to be.

And the optional remote indicator extension enables an additional read out display of each activation to be located where its needed. When the button is pressed both the main unit and the remote indicator display the same result.

The portable, battery powered Random Search Selector is ideal for a variety of applications including temporary selection and search requirements, such as special events. The battery powered model is also available as a ‘Spot Checker’ device with the RSS mounted on a special clipboard, enabling the operator to keep a written record of their search and inspection actions.

battery powered random search selector
Battery Powered Random Search Selector


Portable RSS units are also available with dual check functionality. While standard units present randomly determined ‘Pass’ or ‘Search’ instructions the dual check functionality presents either ‘Pass’, ‘Check 1’ or ‘Check 2’ indicators. This capability has a number or practical applications such as randomly selecting people for either personal searches, bag searches or both personal and bag searches.

dual check random search selector
Dual Check Random Search Selector


How Many People Can be Processed in 60 Minutes Using a RSS?

One of the primary benefits gained from using our Random Search Selectors is maintaining a required throughput while ensuring a high level of security.

Importantly, the Random Search Selector doesn’t require any time to reset after the activation button is pressed. Each subsequent press of the big red button overrides the preceding result which means the number of people, vehicles or items passing through a check point isn’t constrained by the technology.

The number of subjects that can be processed in any given time period is determined by the percentage selected for more thorough assessment and how long those assessments take. The subsequent search and assessment procedures along with the personnel tasked with these responsibilities are the primary constraints on throughput.

With good organisation and experienced operators each RSS button press should take no more than around 3 or 4 seconds per subject.

How to Calculate Throughput Numbers

In many applications its important to consider both security alongside throughput requirements. For example, an educational establishment that needs to check for knives might install a metal detecting knife arch. But if 500 students were required to pass through the arch, at a rate of around 150 per hour, processing all 500 students would take over 3 hours, which is obviously out of the question.

However, if the establishment used 2 or 3 Random Search Selectors, with dip switches set to select around 5 to 10% of students to pass through the metal detecting arch, the time to process all 500 students drops to around 30 minutes.

Its also important to note how Random Search Selectors are not only useful when processing people, they are also extremely useful in many other situations. For example, selecting vehicles entering or leaving from delivery yards, selecting fleet vehicles for safety checks or selecting products from a production line for quality control assessments.

What Happens Next in the Search and Screening Process?

As noted in the previous example, one of the primary applications for Random Search Selectors is in selecting people for further examination. In the example, students selected by the RSS would be prompted to walk through the metal detecting knife arch.

In a workplace application, if employees have given their permission to be searched, they, along with their bags or their lockers, might be searched if randomly selected. These searches should be conducted by trained personnel of the same sex as the subject. Searches should be conducted in front of an appropriate witness and not in public or in front of workmates. The subject should initially be asked to empty things out from their pockets or bags and they should never be asked to remove any clothing that would expose their underwear.

A confidential log should be kept of all conducted searches and this should be monitored by senior management to ensure randomness, fairness and consistency. The employer’s search policy and procedure should be clearly described in the employee’s handbook or in the organisation’s policy documentation.

The specific actions taken in response to prompts from Random Search Selector devices vary. But it should always be ensured that operators are fully aware of their responsibilities and what`s required.

Where are Random Search Selectors Used?

Our Random Search Selectors are now used in a wide variety of applications. Here are some representative examples.

Sales Promotions at Exhibitions

This is an interesting application as it doesn’t relate to crime or safety. Random Search Selectors have been used for promotions at exhibitions wherein visitors to a stand would press the big red button to find out whether they had won a prize.

Schools and Educational Establishments

School and college security measures can involve checking students for weapons, drugs or banned substances. Some establishments work with local police forces to setup temporary security measures to combat knife crime and drug use. Remote Search Selectors play a vital role in ensuring subjects are always randomly selected while making certain everyone gets to their classes on time.

Retailers and Supplier Warehouses

Retailers and warehouse suppliers need to establish policies and procedures to discourage and prevent employee theft. Prevention strategies should include staff training and clearly defined policies that warn of the potential consequences of stealing. Random Search Selectors are being used to deter staff from pilfering while ensuring employees are not delayed when leaving for home at the end of their shifts.

Border Control and Transport Hubs

Those responsible for security and control at our borders and transport hubs need to ensure people, vehicles and goods are able to transit as required but at the same time they need to check for contraband, people smuggling and more.

Our Random Search Selectors take over the responsibility for randomly selecting vehicles, people or containers for more thorough search and inspection.

Manufacturers and Quality Control

Production environments need to maintain quality standards while ensuring production volume isn’t inhibited by test and inspection procedures. Random Search Selectors support these requirements by randomly identifying products or batches for more thorough evaluation, without adversely impacting production schedules.

Vehicle Fleet Management

Managers of vehicle fleets are accountable for the security, dependability and efficiency of their vehicles. They need to routinely carry out safety checks to verify load capacities, ensure tyres are safe, lights are all working and vehicles are roadworthy. Random Search Selectors help them randomly select vehicles for rigorous inspection, without risking accusations of bias or favouritism.

Distribution Depots and Delivery Transportation

Delivery transportation organisations and distribution depots need to randomly select vehicles and cargoes for rigorous inspection when entering and leaving their premises. Random Search Selectors simplify the selection process and ensure its always random.

Random Search Selector Reviews

Here’s just a snapshot of some of our reviews:

Very pleased with the Random Search Selector-Mains Powered Unit. We have forwarded it to our sister company.


Items arrived as promised, as described. Items are very simple to program and use.


It works perfectly. Thank you.

Yoana Marinova

Impressed with the product and the service and delivery was excellent - well done!

Lesley Morrey

The Random Search Selectors are working well , thank you Insight.

Mr Martin C (Sheffield)

Learn More About Our Random Search Selector

Here’s a useful video describing our Hand Held Random Search Selector with dual check capability.


If you have any questions about Random Search Selectors remember we are here to help. Give us a call on 01273 475500 and we’ll provide you with free, expert advice.

This message was added on Thursday 13th April 2023

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