Everything you need to know for a successful confined space protection

Working in a confined space means a lot of risks that require great attention from workers. However, being careful is not enough, you need protective equipment that will optimize your safety.

Of course, a confined space is already very complex to understand, but you also need to understand and analyze the risks you may face. Let's start with the basics: a definition.

What is a Confined Space?

According to the experts at MSA, a confined space is:

  1. A large enough area for workers to physically enter and work in.
  2. A space that has limited or restricted entrances and exits
  3. It is not intended for continuous human occupancy
  4. A space that presents potential hazards to the health and safety of workers because of its layout, hazards, work to be performed, or the mechanisms and processes used.

Before undertaking any work in a confined space, it may be necessary to consult an industrial hygiene expert. They will tell you if you are in compliance with provincial and federal laws and standards.

The Canadian Centre for Occupational Health and Safety warns, however, that " If the confined space cannot be made safe for the worker by taking precautions, then workers should NOT enter the confined space until it is made safe to enter by additional means."

(CCOHS, Confined Space- Introduction. https://bit.ly/3vzvcLe )

Working in confined spaces is complex, especially because of the need for protection, against multiple hazards. Confined spaces require several types of personal protective equipment (PPE), including fall protection equipment, and gas detectors. Let's take a look at why these protections are essential, and how MSA can help you properly protect your employees.

The Importance of Gas Detection in Confined Spaces

When workers need to go inside a confined space, the hazards in the atmosphere can have serious consequences on their health. The various hazards that can be found in the air can slow down, injure, cause illness, and could be fatal. The reasons why the atmosphere could become hazardous and must be monitored are:

  • An atmospheric oxygen concentration below 19.5%. This creates an oxygen deficiency.
  • An airborne concentration of any toxic contaminant above the National Institute for Occupational Safety and Health (NIOSH) or American Conference of Governmental Industrial Hygienists (ACGIH) allowable exposure limit.
  • Combustible airborne dust in a concentration that obscures vision at five feet or less.
  • An atmosphere immediately dangerous to life or health

Good to Know

The following chart illustrates the different gases and vapors according to their danger to humans.

Gases and vapors

Hazard description


The atmosphere has an oxygen concentration of 21%. Oxygen can become dangerous for workers in confined spaces when there is an excess or deficiency of it.

Carbon Monoxide

Carbon monoxide poisons the body by being absorbed into the bloodstream and preventing the blood from absorbing and carrying oxygen to the cells and organs.

Carbon Dioxide

Carbon dioxide is not only capable of displacing oxygen in confined spaces, but it is also toxic.

Hydrogen Sulfide

It is a highly toxic gas that irritates the eyes, nose, throat, and respiratory system. High concentrations can cause a coma and even death.

When it comes to which gas detector to choose, MSA recommends 5 key aspects to consider. Depending on your work environment, it is important to choose a gas detector that will be effective, but also durable.

Here are the most important things to consider:

  • Robustness
  • The quality of the technology (sensors)
  • The battery life
  • Speed and simplicity of maintenance
  • Cloud connectivity

Learn more about Altair gas detector series


The Importance of Fall Protection in Confined Spaces

For successful confined space entry and exit, it is important to have the right fall protection equipment that fits the complexity of the work area. To accomplish this, a full-body safety harness, safety tripod, as well as a connection device are necessary to properly protect the worker.

When entering a confined space, the fall protection system will allow the worker to go down with control. This will prevent accidental falls. The equipment and tools used by workers can also be lowered thanks to this same system.

MSA reminds you that it is essential to always wear a full body safety harness, even during a horizontal entry, to allow for a quick rescue in case the worker becomes unresponsive. A lifeline should be attached to the worker's safety harness.

The safety tripod should be equipped with a mechanism to help lift the worker. Pulling a worker out of a confined space requires a lot of strength and is very difficult for one person to do alone.

As for the safety harness, it should be connected to a self-retracting lifeline with a rescue function. This self-retracting lifeline allows the confined space worker to move freely. If, however, the worker needs to be extracted from the confined space, the lifeline's rescue function will allow the worker to be effectively extracted.


Discover MSA’s safety harness


Since confined space protection is complex, you need the best protective equipment for gas detection and fall protection.

Gas Detection with MSA

MSA Altair 4XR Dust-resistant and Waterproof Multigas Detector

  • SPI code: GDE124
  • Reliable and robust multigas detector
  • Simultaneously measures up to four gases
  • Quick-response MSA XCell® sensors
  • Safety io compatible
  • Provide real-time incident knowledge to any team members when linked to the MSA Altair Connect app
  • Four-year sensor life (60% longer than the industry average)
  • 24-hour run time
  • Secure grip
  • Designed to resist a drop of up to 20 ft. (6m)
  • Saves users more than 50% on calibration gas, replacement sensors, and maintenance
  • 95+ DB alarms
  • Ultra-bright LEDs
  • Large buttons and high-contrast screen
  • MotionAlert option tells others that the user is immobilized
  • InstantAlert features a manual alarm to alert others of a dangerous situation

MSA Galaxy® GX2 No-Charging Automated Test System for Altair 4/Altair 4X, 1 Valve

  • SPI code: GDE422
  • 1 valve
  • Non-charging
  • Provides automated calibration of MSA ALTAIR gas detectors
  • Color touch screen for ease of setup and viewing
  • Extremely simple to use
  • Optimized for use with MSA’s XCell® Sensors
  • Provides up to 50% cost of ownership reduction
  • At-a-glance indicators include low calibration gas volume, expiration warnings, and test stand status
  • MSA Link Pro Software provides proactive safety management
  • 18 languages available for test stand and MSA Link Pro Software

MSA 4 Gas Mix Calibration Testing Gas Cylinder, 34 Litres

  • SPI code: GCA410
  • Help ensure the use of correct gas
  • Provide the gas cylinder the required information for a successful calibration
  • It quickly transfers stored information such as cylinder expiration date and pressure level to a connected PC
  • Rugged instrument
  • Ergonomically designed rubber
  • Superior grip
  • Water and dust resistant
  • Unsurpassed durability
  • Survives a six-foot drop test
  • Utility: 34L Econo-Cal Quad gas 60 ppm CO, 20 ppm H2S, 15% O2, 1.45% CH4

Fall protection with MSA

green and black harness MSA

MSA V-FIT Construction Harness, Back & Hip D-Rings, and Quick Connect Leg Straps

  • SPI code: CHA328
  • Webbing is routed across the chest for a secure and comfortable fit
  • Shoulder padding responds to your movement to conform to your body, eliminating pressure points
  • Patented leg strap design keeps leg straps in place
  • The RaceFLEX Buckle creates an athletic cut
  • More natural fit
  • Improving upper torso movement on the job
  • Pull-down adjustment allows you to get the right fit quickly and easily
  • Quick and easy attachment
  • keeps your back D-ring free for other uses
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MSA Workman Confined Space Entry Kit 50'

  • SPI code: 10174589
  • Make confined space entry with vertical descent easy
  • Internal leg-locking mechanism
  • Maximum height indicator
  • Cut-resistant leg pin
  • Retention chains
  • Recessed product labels
  • Reduced weight and integral carry strap
  • The Workman Tripod can be set up and dismantled without the use of tools
  • Approved: CSA Z259.2.2
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MSA Workman Self-Retracting Lifeline with Rescue Mode and 50' Stainless Steel Cable

  • SPI code: CTR028
  • Integrated emergency winch
  • Ideal for rescue in confined spaces
  • Its retrieval capability allows the fallen worker to ascend or descend to a safe location
  • Ergonomic, stainless steel carrying handle can also be used as anchorage connection point
  • Built-in shock absorber
  • Robust aluminum housing with thermoplastic bumpers
  • Self-locking swivel snaphook with load indicator.