Physical Security Controls: An Overview

Physical security controls are mechanisms designed to deter unauthorized access to rooms, equipment, document, and other items. In contrast to technical and administrative controls, physical security controls are tangible. Common examples of physical security controls include fences, doors, locks, cameras, and security guards.

Security controls can fall in multiple categories. For instance, security cameras and most modern alarm systems are both technical and physical in nature.

Security controls can also be distinguished based on their goal:

  • Preventative controls aim to prevent security incidents;
  • Detective controls aim to detect incidents as they happen, or after the fact;
  • Corrective controls aim to mitigate the impact once an incident has occurred;
  • Deterrent controls aim to deter attackers from making an attempt;
  • Compensating controls can be used in case another control won’t work.

Physical security controls can achieve any of the above aims. Below, we’ll get into an overview of some common physical security controls.

Security Guards

Security guards offer multi-faceted protection against physical intrusions. They may check identification cards to determine if someone is authorized to enter a building or area, or act as a deterrent to unauthorized individuals considering an entry attempt. Additionally, they might monitor security camera feeds for suspicious behavior, taking action if something unauthorized occurs.

Fences, Cages, and Walls

Fences, cages, and walls enhance security by creating physical barriers that people need to cross to access specific spaces or equipment. Often, these act as a single layer in a broader security plan, delaying or preventing those who aren’t authorized to access particular areas from gaining entry.

When encountering a fence, cage, or wall, unauthorized individuals have to navigate the barrier. For example, they might have to climb a fence, cut a cage, or break through a wall. It creates an extra step for anyone looking to get into an area, making it harder and upping the time required to reach spaces or equipment.

Doors with Locks

Lockable doors are another barrier to entry. They create a point of entry for authorized individuals while preventing those who aren’t allowed to simply walk into an area.

There are a variety of locks available that can enhance physical security. Along with traditional keys, combination, PIN code, RFID scanner, and biometric locks are all available. Each option has pros and cons, offering varying levels of overall security.

PIN and combination locks allow every authorized person to potentially have their own code, making entries trackable. The risks of this approach include an authorized person guessing a code, as well as authorized individuals writing theirs down and it being found.

RFID scanner locks typically work in conjunction with an employee ID card. This approach is also trackable and eliminates the risks associated with guessed or written down codes. However, if an ID ends up in the hands of an unauthorized person, they could use it for entry.

With biometric locks, a physical characteristic of the authorized individual is what opens the door. For instance, fingerprints, voiceprints, facial scans, and similar biological data all fall in this category. Generally, that makes this option the most secure. However, the systems can be costly.

ID Cards

ID cards play a significant role in physical security. They allow security guards or others in the vicinity a to determine if a person is authorized to be in an area quickly. Plus, they can serve as keys on security doors, depending on the types used.

Security Alarms

Alarm systems detect unauthorized entry and alert select personnel of an intrusion. Since the systems are typically device-based – such as sensors on windows or doors – they qualify as physical security, even though there’s a technical component.

Along with detection capabilities, security alarms can be a deterrent. If signage announcing their presence is prominently displayed throughout an area or facility, unauthorized individuals may decide not to attempt an entry since their odds of getting caught are higher.

Surveillance Cameras

With surveillance cameras, you gain the ability to observe areas of a facility even if you aren’t physically in that area. They allow for the monitoring of behavior, increasing the odds that suspicious activity or attempts at unauthorized access are noticed quickly. Additionally, they let you to create records of what happens in an area, giving you video footage that you can review after an attempted or successful breach.

The presence of security cameras can also act as a deterrent. Like security alarms, if an unauthorized person knows that cameras are recording their actions, they may be less inclined to attempt to gain entry.


When it comes to overlooked physical security measures, lighting is one of the biggest. When an entry point with restricted access is well lit, it makes the spot less attractive to anyone who isn’t authorized to enter. The chances that breaching a physical barrier will be noticed go up significantly if the space is brightly illuminated. Plus, it ensures that camera footage of the individual is as clear as possible.

Both traditional always-on lighting and motion-detecting lights can be strong deterrents. However, it’s crucial to replace burned-out bulbs immediately to ensure there are no windows of opportunity.

Equipment Disposal Tools

Old equipment that contains sensitive data or was previously connected to an internal system isn’t something that should be thrown out in your regular trash or recycling without some extra steps. Failing to dispose of it properly means that an unauthorized individual may be able to review company data or access a private system simply because the information or permissions weren’t properly removed from the device.

While many solutions to this issue are technical in nature, there are also options that qualify as physical security. A hard drive shredder is a prime example, though it isn’t the only tool in this category.

Document Disposal Tools

Properly disposing of sensitive documents is another form of physical security. Micro-cut shredders – also called security-cut or particle-cut shredders – are typically the most secure, as they cut papers into the tiniest possible pieces, making reassembly practically impossible. That makes it ideal for incredibly sensitive documents. For medium security, a locking cross-cut shredder may be sufficient.

However, you also need to factor in the recycling company and pickup approach you use. If the paper will sit in an unsecured recycling can in a publicly accessible area or is picked up by a non-specialty service, like a city or county waste company, using micro-cut shredders for everyone may be a better idea. If the paper is in a secured can and picked up by a specialty, security-oriented paper recycling service, using a less robust shredding option might be an option.

About the Author

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Catherine Reed

Catherine Reed is a writer and researcher with experience writing about a wide variety of topics including personal finance, technology, and staffing.