Face Shields, Pocket Masks and Bag-Valve Masks for CPR

Rescue breaths remain an important part of cardiopulmonary resuscitation, particularly in situations involving children, drowning, hypoxia or respiratory arrest. Although mouth-to-mouth ventilation can be effective, many trained first aiders prefer to use a barrier or ventilation device when one is available. barriers are partiality value when the First Aider is concerned about giving CPR breaths, perhaps due to the casualty being covered in saliva, vomit or blood. As you will read below come barrier also make CPR easier and more effective. The three devices most commonly encountered are:

• CPR face shields
• Pocket masks
• Bag-valve masks (BVMs)

They all have the same basic purpose — getting air into the casualty’s lungs — but they differ significantly in the protection they provide, the skill required to use them and the situations for which they are best suited.

Current Resuscitation Council UK guidance continues to emphasise effective ventilation as part of basic life support. If rescue breaths are provided, each breath should contain only enough air to make the casualty’s chest begin to rise, avoiding excessive ventilation. This article will assum you are aware of the current CPR protocols, if not then please read another of our articles first How to give CPR and use an AED.

CPR Face Shields

A CPR face shield is the simplest form of barrier device. It is normally a thin sheet of plastic containing a one-way valve or filter which is positioned over the casualty’s mouth.

Many are small enough to be folded into a keyring pouch. The purpose of the shield is primarily to create a barrier between the rescuer and casualty while allowing mouth-to-mouth ventilation.

How to Use a CPR Face Shield

• Place the shield over the casualty’s face with the valve positioned over the mouth.
• Open the airway using an appropriate airway manoeuvre, normally the head-tilt/chin-lift technique where spinal injury is not suspected.
• Pinch the casualty’s nose closed.
• Seal your mouth around the valve and give a rescue breath over approximately one second.
• Look for the chest to begin to rise.
• Allow the chest to fall before giving the second breath.

Advantages of a Face Shield

The major advantages are its simplicity and size.

A face shield is:

• extremely compact;
• inexpensive;
• simple to carry;
• quick to deploy;
• useful when no larger ventilation equipment is available.

This makes it particularly suitable for iirst aiders who want a barrier device that can remain permanently in a personal first aid pouch or lifejacket pocket.

Limitations of a Face Shield

A face shield does not provide the same physical separation between casualty and rescuer as a pocket mask (see below).

The rescuer’s face still has to come very close to the casualty and the effectiveness of ventilation remains heavily dependent on obtaining a good mouth seal and maintaining an open airway. The rescuers hand are likely to come into contact with the very fluids (vomit blood, saliva) tht the rescuer is trying to avoid and in turn there is a risk tat the rescuer cintaismte the clean (top) side of the face shield whil giving CPR. Most basic face shields also provide no practical means of attaching supplemental oxygen. Fo these reason Chieftain TRaiming reccomnds, “While a face shield is better than nothing, we recommend you carry a pocket mask (and/or BVM) instaed of a face shield. A pocket mask is generally a more capable ventilation device”.

Pocket Masks

A pocket mask is a shaped resuscitation mask which fits over the casualty’s mouth and nose.

Unlike a simple face shield, it creates a physical air space between the casualty and rescuer.

Most modern resuscitation masks contain a one-way valve, and many include an inlet through which supplemental oxygen can be supplied.

Resuscitation Council UK equipment standards include a pocket mask with an oxygen port among airway and breathing equipment recommended for immediate availability in primary care settings.

How to Use a Pocket Mask

• Position yourself at the casualty’s head.
• Place the narrow end of the mask over the bridge of the nose and the wider end between the lower lip and chin.
• Maintain an open airway using head tilt and chin lift where appropriate.
• Hold the mask firmly against the casualty’s face to create an airtight seal. A commonly taught grip is the C-E technique: the thumb and index finger form a C around the mask, the remaining fingers lift the jaw towards the mask.
• Blow through the one-way valve for approximately one second.
• Give only enough air to make the chest begin to rise.

With the aid of a face shield, CPR just got easier, firstly you no longer need to pinch the casualties nose as the mask covers nose and mouth. Secondly getting a seal around the mouth is much easier as you simply press down on the face mask and then seal your lips around the tube (like blowing through a straw).

Why Pocket Masks Are Useful

Pocket masks offer several practical advantages over basic face shields.

They provide:

• a far greater separation between rescuer and casualty;
• a more controlled seal;
• a one-way ventilation valve;
• potentially better control of the airway;
• the ability on many models to connect supplemental oxygen.

They are also reusable if cleaned and maintained in accordance with the manufacturer’s instructions.

For professional first aiders and watersports instructors, a pocket mask can therefore be a useful compromise between simple mouth-to-mouth ventilation and more advanced bag-mask ventilation. The pocket mask is contained within the Cat C First Aid kit carried onboard commercial vessels, its is also a compulsory item board safety boats at RYA dinghy, keelboat, multihull, wining windsurf, PWC  and powerboat training centres.

Pocket Masks and Oxygen

Some pocket masks have an oxygen connection. When supplemental oxygen is available and the rescuer is appropriately trained, oxygen can be supplied through the mask while rescue breaths are delivered. The precise oxygen concentration received by the casualty depends on factors including:

• oxygen flow;
• mask design;
• the quality of the seal;
• the casualty’s ventilation.

Oxygen equipment should only be used by people who have received appropriate training and in accordance with organisational procedures.

Bag-Valve Masks

The bag-valve mask, usually abbreviated to BVM, provides positive-pressure ventilation without the rescuer placing their mouth close to the casualty.

It consists of three principal parts:

Bag → Valve → Mask

It is sometimes colloquially called an Ambu bag, although Ambu is actually a manufacturer’s trade name.  The flexible self-inflating bag is squeezed by the rescuer, pushing air through a one-way valve and mask into the casualty’s lungs. Many BVM systems can also be connected to an oxygen supply and reservoir.

Resuscitation Council UK lists a self-inflating bag with reservoir and appropriate clear face masks among airway equipment that should be immediately available in acute clinical settings. BVMs are part of the Category M Mediacl Kits carried on board SOLAS vessle and coded workboats and yachts that operate more than 60 miles from a safe haven.

BVM Ventilation Requires Training

A bag-valve mask may look straightforward, but effective BVM ventilation is considerably more difficult than simply squeezing the bag.

Three things must happen simultaneously:

1. The airway must be open.

2. The mask must form an effective seal around the casualty’s face.

3. The correct volume of air must be delivered.

Failure in any one of these areas can result in inadequate ventilation. Excessive ventilation can also cause problems. The aim remains: one breath over approximately one second, producing visible chest rise.

Current Resuscitation Council UK adult advanced life support guidance specifically says to optimise airway patency and mask seal and, where necessary, use a two-person technique for bag-mask ventilation.

One-Person BVM Technique

When only one trained rescuer is available, one hand normally holds the mask to the casualty’s face while maintaining the airway.

The other hand squeezes the bag. The rescuer commonly uses the C-E grip:

C — Thumb and index finger hold the mask

E — Remaining fingers lift the mandible

This can be effective, but maintaining a reliable mask seal while simultaneously managing the airway can be difficult. For that reason, BVM ventilation is much more reliable when performed by two trained rescuers.

Two-Person BVM Technique

The preferred technique when sufficient rescuers are available is usually a two-person bag-mask technique.

One rescuer concentrates entirely on:

• opening the airway;
• positioning the mask;
• holding the mask with both hands;
• lifting the jaw;
• maintaining the seal.

The second rescuer squeezes the ventilation bag.

Resuscitation Council UK’s 2025 education guidelines specifically recommend teaching two-person ventilation when using a self-inflating bag and mask. This separation of tasks generally allows a much better mask seal and more reliable ventilation.

How Hard Should You Squeeze a BVM?

A common mistake is squeezing the bag too hard or too quickly. The casualty does not need the entire contents of an adult ventilation bag forced into their lungs. Instead:

• squeeze only enough to make the chest visibly rise.
• deliver the breath over approximately one second.

Excessive ventilation may force air into the stomach as well as the lungs and can contribute to gastric inflation, regurgitation and aspiration. It can also interfere with the circulation generated by chest compressions. The goal is therefore effective ventilation, not maximum ventilation.

BVM and Supplemental Oxygen

A self-inflating BVM can work using ordinary atmospheric air. It does not need an oxygen cylinder to inflate. However, many BVMs can be connected to:

• supplemental oxygen;
• an oxygen reservoir.

With the appropriate equipment, oxygen supply and technique, this can substantially increase the oxygen concentration delivered to the casualty. Oxygen administration should nevertheless be undertaken only by rescuers who are appropriately trained and authorised to use the equipment.

Face Shield vs Pocket Mask vs BVM

 

Device	Main advantage	Main limitation	Relevance
Face shield	Tiny, cheap and easy to carry.	Limited separation and seal control	Better than nothing
Pocket mask	Good barrier and improved mask seal	Requires some training and is larger	Mandatory on Board all coded vessels and RYA Safetyboats
Bag-valve mask	Allows ventilation without mouth-to-mouth and can be combined with oxygen. Far less tiring for the First Aider	Requires significantly more skill	Mandatory on Board Cat 1 yachts & workboats and all SOLAS ships

There is therefore no single device that is automatically appropriate for every rescuer. A lone member of the public carrying a keyring face shield has very different equipment requirements from a professional first aid team carrying oxygen, suction equipment and a BVM.

What training is available?

At Chieftain Trining the following techniques are taught on the following courses (this may not be reflected at other training centres).

	Face Shield	Pocket Mask	BVM
RYA First Aid	✅	✅
16 Hour outdoor First Aid	✅	✅
HSE Emergency First Aid at Work	✅	✅
HSE First Aid at Work	✅	✅	✅
HSE First Aid at Work Refresher	✅	✅	✅
STCW Elementary First Aid	✅	✅
STCW Medical First Aid		✅	✅
STCW Medical Care		✅	✅
STCW Medical Care Update		✅	✅
Paediatric First Aid	✅	✅

 

Which Device Should I Use During CPR?

The BVM is the least tiring for the First Aider and therfore provides the best CPR, if you have one and the First Aider is trained and confident in its use. The pocket mask it more common but also require training. However, do not create a prolonged interruption in CPR while searching for or assembling ventilation equipment. If a face shield or pocket mask is immediately available, it can normally be incorporated quickly. A BVM is more likely to require additional personnel and preparation. Resuscitation Council UK emphasises that interruptions to chest compressions should be kept to an absolute minimum.

Drowning Makes Ventilation Particularly Important

For a casualty who has drowned, oxygen deprivation is usually central to the cardiac arrest. This makes effective rescue breaths particularly important.

A face shield, pocket mask or BVM may therefore be especially valuable in a watersports or marine  environment where drowning is a foreseeable emergency. The device does not change the fundamental objective: open the airway and deliver effective breaths that make the chest rise.

For trained teams with appropriate equipment, a pocket mask or BVM will make this ventilation easier and will provide greater separation between rescuer and casualty.