Boosting School Safety with Knife Arches

The recent, tragic murder of a schoolboy, by a fellow pupil using a hunting knife, is prompting many schools and colleges to sensibly implement robust anti-knife security measures. Read our latest blog to learn more.

On the 3rd of February 2025, Mohammed Umar Khan, aged 15, took a hunting knife with a 13cm serrated edged blade into All Saints High school, Sheffield. At 12.15pm he used the knife to stab fellow pupil Harvey Willgoose two times, in the chest and abdomen, causing his death. The two students had previously been on good terms but had fallen out over a fight between two other students. Evidence clearly showed that Mohammed Umar Khan had purposely concealed the knife and ignored a friend’s request that he hand over the knife to avoid doing “something stupid”.

The parents of Harvey Willgoose, who have established a youth club in his memory, have campaigned against knife crime and to raise awareness of the issue. Mrs Willgoose reported that her son had avoided school, partly due to anxiety caused by the coronavirus pandemic, but also because of a fear about knives in school. She urged parents to ask their children if they have ever known of any pupils bringing knives into school. 

Harvey’s parents have repeatedly called for airport-style metal detecting security knife arches to be installed in UK schools. Some people are surprised that this security measure is now considered necessary, but children and their parents are frightened by the possibility that pupils might be concealing knives and what can happen.

What the Government Has Said

The Department for Education (DfE) has stated that schools are responsible for setting their own security measures (including screening for knives) and it is for each school to decide on the precautions to take, including whether to use walk-through metal detectors or handheld wands. In a government response to a parliamentary committee report, they said: 

“The possible use of screening arches – in schools and other places – is one of a range of measures that can be used locally to tackle knife crime.”

But the Government has acknowledged that metal detecting security devices may not be appropriate for every school and therefore don’t recommend compulsory introduction of knife arches in schools. The government emphasises that incidents involving knives in schools are rare and recommends that every school and community needs to make decisions for themselves. 

In practice what this means is that if a school (or academy) believes it is appropriate, it can install knife arches or use hand-held security scanners, but it must assess the need, engage with local police for advice, consider costs, and ensure the security measures work with the school’s overall safeguarding strategy.

Knife Arches in Schools

It has been reported that schools have quickly become the biggest purchasers of metal detecting security devices, outstripping the police and security services. Evidence and rigorous data on the impact of these enhanced security measures is still very limited, but there have been many positive comments. 

It needs to be recognised that introducing screening devices and procedures can affect the school atmosphere. If enhanced screening makes pupils feel overly policed or anxious, there could be unintended consequences. Some reports describe how pupils may feel less safe in schools with knife arches because the presence of these devices suggest a heightened level of threat. It is clear that schools need to manage the need for robust security with sensitivity, communicate very clearly and ensure security measures are effectively integrated with their safeguarding policies. 

Importantly, metal detecting knife arches in schools serve two distinct functions. They enable staff to detect prohibited items, including knives, and prevent them from being brought onto school premises. 

They also act as a highly visible deterrent. The presence of a knife arch tells pupils that if they attempt to bring a knife into school they will be caught and the risk of being caught in possession of a knife is enough to put them off. Pupils who have been consulted over the presence of knife arches in their schools have acknowledged that if a metal detecting arch was in place at Harvey Willgoose’s school his attacker wouldn’t have been able to conceal the hunting knife he used.

Here are some examples of schools that have successfully implemented metal detecting security technology.

Milton Keynes College

This further education college, prompted by a local knife incident that put the college in lockdown, trialled walkthrough metal detecting knife arches at two sites from October 2023. The initial trial started with just one machine but this was then expanded to include a second arch. 

The cities Community Safety Partnership (SaferMK) carried out a survey finding that 86% of students said that the metal detecting knife arches made them feel safe and 83% said they were happy with the technology being used. The college leadership acknowledged the enhanced security measures as a success.

Dudley Academies Trust

This multi-school trust worked with West Midlands Police to install metal detecting arches at the entrances of its secondary schools. The installation started with St James Academy where students now walk through metal detectors as they enter the school at the start of the school day.

A survey, conducted by the trust, demonstrated “overwhelming support” from parents and carers. The police inspector overseeing the project said the screening arches provide “added peace of mind” for children, parents, staff, and visitors.

Feedback from students has been mixed with some acknowledging that the presence of these security checks are both scary, when the reason for their implementation is considered, but at the same time reassuring. 

Penistone Grammar School

A knife arch was donated to Penistone Grammar School by the foundation set up in memory of Harvey Willgoose. The school has emphasised that it doesn’t have an issue with knives and the portable knife arch was being implemented as a proactive safety measure. The portability of this knife arch means it can be easily shared across the community as a valuable educational tool.

The school principal has observed that pupils feel comfortable walking through the arch and it doesn’t present any inconvenience for them. Students at the schools have said they didn’t think they needed a device like this but neither did the school at which Harvey Willgoose was sadly killed.

Knife Arch Options

For any schools, academies or colleges considering the introduction of metal detecting knife arches there are basically two types to consider:

1. Fixed or permanent knife arch installations
2. Portable or temporary knife arches.

There are both advantages and disadvantages associated with each option.

Fixed or Permanent Knife Arches

Fixed or permanent security metal detecting knife arches will be familiar to anybody who has travelled through a UK airport or transport hub. This design of knife arch is typically installed in schools and colleges at main entrances or designated entry points.

This form of permanently installed knife arch offers a number of important advantages. The continuous, highly visible presence of a metal detecting arch, which students and staff are required to walk through, acts as a powerful deterrent. The visual presence signals a school’s zero tolerance toward knife carrying and emphasises the establishment’s security and child-safeguarding priorities.

Another advantage is that this form of metal detecting arch is powered from the mains and doesn’t require any setup or configuration, once installed. These arches can be integrated into a school’s access-control system and work alongside CCTV and attendance recording systems.

Permanent metal detecting arches can efficiently and effectively handle high levels of footfall which is vitally important at the start of the school day, when pupils and staff are rushing to get to their classes on time.

Its also important to be aware of disadvantages associated with fixed or permanent metal detecting knife arches. One of the main disadvantages is cost. Fixed metal detecting knife arches tend to be more expensive to buy and install. But it has been pointed out that the potential impact of not implementing rigorous, reliable anti-knife security can be far more costly.

Another potential disadvantage is the aesthetic and psychological impact of installing permanent security screening technology at school entrances. Some critics suggest these machines create a prison-like atmosphere and contribute to feelings of anxiety amongst pupils. It has also been pointed out that the presence of a permanent security metal detection facility can appear to suggest that a school has a knife problem, when it doesn’t.

Fixed or permanent metal detecting arches generally can`t be easily moved or relocated to alternative positions, which can be inconvenient for some establishments. However, some models can be fitted with castors, enabling the arch to be wheeled out of the way when not in use. Permanent metal detecting arches need adequate space along with a reliable mains power source which can be challenging, especially in smaller school entrance areas. 

Portable or Temporary Knife Arches

Lightweight, portable knife arches, powered by rechargeable batteries, can be erected as needed, moved to various entrance points and shared between establishments. But there are both advantages and disadvantages associated with these devices.

Portable knife arches provide flexibility, enabling them to be selectively deployed, as needed. They tend to cost around the same as some permanent models, don’t require any permanent wiring and have low maintenance costs.

While this form of metal detecting knife arch is easy to use, time and familiarity is needed to ensure they are erected correctly. And repeated erecting and dismantling can potentially damage connectors, causing the units to fail or malfunction. Reliance on battery power also means batteries must always be charged and maintained.

The fact that this form of walkthrough arch isn’t permanent means they tend to be less intimidating for pupils, reducing the sense of permanent surveillance. This form of portable, temporary metal detecting arch is perhaps more suitable for smaller schools and applications where flexibility and lower initial costs are important.

Hand-Held Metal Detectors

Another important technological tool, commonly used to screen people and baggage for prohibited items, is the hand-held metal detector or metal detecting wand. These devices offer various advantages and disadvantages when compared with walkthrough knife arches.

At the top of the list of key advantages is cost. Hand-held metal detecting wands are far less expensive than walk-through arches. This low cost can enable establishments to equip themselves with multiple devices allowing several staff members to simultaneously carry out security screening.

Hand-held scanners are totally portable, enabling them to be used wherever they are required without the need for any installation. They can be taken on school trips and used to screen baggage as well as people. 

Hand-held devices are far less intrusive and visible than walkthrough arches and therefore don’t introduce ‘prison like’ security concerns into a school. They are very easy to use, don’t require any special training and are widely relied-upon by the police and security operatives. Handheld metal detectors are often used alongside metal detecting arches to accurately pinpoint exactly where a detected metal item is located on a persons body.

A big disadvantage of hand-held detectors for mass screening is that they require staff to scan each subject individually, which takes time and is susceptible to errors. This makes reliance on these devices for rigorous security unsuitable for security screening every pupil and staff member at the busy start of a school day. 

Another disadvantage is that while a walkthrough scanner involves zero interaction with the subject, using a handheld device requires close proximity, which raises privacy and other concerns.

If subjects are being randomly selected for security screening with hand-held metal detectors, this random selection process can lead to accusations of bias and prejudice. This risk can be mitigated by using our Random Search Selector devices that ensure every subject, selected for scanning, is chosen entirely at random.

Talk to Us About Your Requirements

As previously noted, schools, academies and colleges are now taking the need for robust, reliable knife-detecting security very seriously. They are sensibly investing in the safeguarding policies, procedures and technologies they need in order to provide pupils and parents with confidence in the safety of their establishments. 

If you are considering what’s needed for your school or college we can help. We have the technology as well as the experience necessary to implement reliable anti-knife security measures that keep pupils, staff and visitors safe and secure.

Read our previous blog posts:

• BBC Finds Children as Young as Four Taking Knives into Schools
• Available Now - Garrett Guide Metal Detector Wand
• Schools and Colleges Face Growing Security Challenges

If you have any questions about school or college security, or if you have any special requirements, remember we are here to help. Give us a call on 01273 092921 and we’ll provide you with free, expert advice.

For more information on Boosting School Safety with Knife Arches talk to Insight Security