This guide is designed to give additional information on some of the technical terms and procedures which may be found throughout this website.

You can also find more information in our FAQ.

Aerosol-generating procedures (AGPs)

Certain medical and patient care activities that can result in the release of airborne particles (aerosols). AGPs increase the transmission of airborne viral and bacterial infections. Aerosol can be generated during positive patient ventilation, chest compression (prior to tracheal intubation), oral and airway suctioning (without a closed system), when using of high flow oxygen greater than 6L/min, coughing, sneezing or expectorating. The SARUS-CPR hood provides personnel with protection from exposure and contamination with aerosols, droplets, saliva, blood and vomitus.

Airborne transmission

The spread of infection from one person to another by airborne particles (aerosols) containing infectious agents. The SARUS-CPR hood significantly reduces widespread airborne spread of aerosol particles containing viruses and bacteria like TB.

Airborne particles

Very small particles that may contain infectious agents. They can remain in the air for long periods of time and can be carried over long distances by air currents. Airborne particles can be released when a person coughs or sneezes, and during aerosol generating procedures (AGPs). ‘Droplet nuclei’ are aerosols formed from the evaporation of larger droplet particles. The SARUS-CPR hood acts as a barrier to the spread of both small and large particles.

Airborne precautions

Measures used to prevent and control wider infective spread of aerosols (less than or equal to 5μm) generated from the respiratory tract of one individual to a mucosal surface or conjunctivae of another individual. Aerosols are small enough to penetrate the respiratory system at the alveolar level. The SARUS-CPR hood acts to contain airborne pathogens transmitted within the waterproof textile hood.

Airway Operators

The first-responders who place the SARUS CRP hood over the patient, tighten the two neck draw strings and carry out ‘Bag and Mask’ ventilation together, while other personnel carry out chest compressions, ECG deployment and cardioversion if required.

Bacterial/Viral filters

Filters used during ventilation for trapping bacteria and viruses, preventing cross-contamination. They consist or electrostatically charged interlocking fibres which trap bacteria and viruses, which are further attracted to these fibres by the positive and negative electrostatic charges on the fibres. The fibres have a hydrophobic coating that repel any water droplets containing bacteria or viruses thus preventing the passage of these organisms. Direct filtration removes large particles (>1 μm) whose diameter is greater than that of the pores of the filter membrane. Inertial impaction results in the removal of smaller particles (0.5–1.0 μm in diameter) by collision within the filter material. Diffusional interception removes very small particles (<0.5 μm). Manufacturers offer filters with efficiency levels of >99.9%. Note that coronaviruses themselves are smaller than the minimum sized particles that most ‘viral’ filters are able to remove. However, the particles of respiratory secretions with which coronaviruses are associated when in aerosol form are larger and able to be filtered by these devices. Reference to ‘viral’ filters refers to their ability to filter aerosolised respiratory secretions that potentially contain virus, rather than the ability to filter the virus itself. The SARUS-CPR hood has an integrated bacterial/ viral filter which can’t be removed or dislodged. It also has an integrated air-escape viral filter used to manage any potential pressure build up within the hood.

Bag and Mask ventilation

The standard method for rapidly providing rescue ventilation to patients with apnoea or severe ventilatory failure. An emergency procedure carried out to tide over until intubation is done. The SARUS-CPR hood has been designed to facilitate standard ‘bag and mask’ ventilation by trained CPR personnel. All of the fittings are standard and appropriate for easy attachment and removal from a ventilation bag.

Bag-valve-mask (BVM)

Bag valve mask, sometimes known by the proprietary name Ambu bag or generically as a manual resuscitator or “self-inflating bag”, is a hand-held device commonly used to provide positive pressure ventilation to patients who are not breathing or not breathing adequately. The self-inflating bag is used together with the SARUS CPR hood in order to ventilate the patient and introduce high flow oxygen during CPR.

Contact allergy

All components of the SARUS-CPR hood that are in contact with the patients skin have been selected to be Latex free. The elasticated draw strings do contain Latex but are completely sheathed from direct skin contact.


CPR is an abbreviation for cardiopulmonary resuscitation. The manual application of chest compressions and ventilations provided to patients in cardiac arrest, done in an effort to maintain viability until advanced help arrives.
CPR is an essential component of basic life support (BLS), basic cardiac life support (BCLS) and advanced cardiac life support (ACLS). The SARUS-CPR hood supports the airway management and ventilation component of CPR.

CPR training

Personnel who use the hood are encouraged to adhere to their current CPR training and skills, with particularly with reference to ‘bag and mask’ ventilation. The SARUS-CPR hood simply enhances their own safety and the safety of other people in the immediate vicinity. The closed Yankauer suction system is also familiar and easy to use in an emergency.

Closed suction tube

A sheathed suction tube used during clinical suctioning to clear retained or excessive oral, respiratory and gastrointestinal tract secretions in patients who are unable to do so effectively for themselves. Helpful in limiting environmental, personnel and patient contamination. The SARUS-CPR hood incorporated an adult sized Yankauer suction tube and an on-off valve that can be attached to suction tubing.

Contact precautions

Measures used to prevent and control infections that spread via direct contact with the patient or indirectly from the patient’s immediate care environment (including care equipment). This is the most common route of COVID-19 infection transmission. The SARUS-CPR hood significantly reduces the possibility for contact contamination of personnel, clothing and bedding by potentially infective bodily fluids.

Contact transmission

Contact transmission is the most common route of transmission and consists of 2 distinct types: direct contact and indirect contact. Direct transmission occurs when microorganisms are transmitted directly from an infectious individual to another individual without the involvement of another contaminated person or object (fomite). Indirect transmission occurs when microorganisms are transmitted from an infectious individual to another individual through a contaminated object or person (fomite). The SARUS-CPR hood significantly reduces both direct and indirect routes of disease transmission.

COVID-19: infection prevention and control guidance

Guidance issued jointly by the Department of Health and Social Care (DHSC), Public Health Wales (PHW), Public Health Agency (PHA) Northern Ireland, Health Protection Scotland (HPS)/National Services Scotland, Public Health England (PHE) and NHS England as official guidance. The SARUS-CPR hood enhances patient and personnel safety and acts to simplify any doubt related to guidelines and how personnel should respond in an emergency.

Droplet precautions

Measures used to prevent, and control infections spread over short distances (at least 1 metre or 3 feet) via droplets (greater than 5μm) from the respiratory tract of one individual directly onto a mucosal surface or conjunctivae of another individual. Droplets penetrate the respiratory system to above the alveolar level. COVID-19 is predominantly spread via this route and the precautionary distance has been maintained at 2 metres in care settings. The SARUS-CPR hood significantly reduces the potential for droplet spread.

Droplet transmission and containment

The spread of infection from one person to another by droplets containing infectious agents. This is usually caused by coughing. If the patient responds to CPR, their usual response is to cough. These explosive, coughed droplets will be contained within the hood.

Dual engineering design

The SARUS-CPR hood simultaneously improves safety in two ways. It speeds up patient response times, potentially saving lives and enhances the safety of CPR first-response personnel by creating a fluid barrier. It is engineered to have two neck seals in order to reduce potential air flow. It integrates two key components used in CPR ventilation, a viral filter/ size 5 anaesthetic mask that can be attached to a ventilation bag and a separate closed oral suction tube, used to clear the upper airway. The size 5 anaesthetic mask can be interchanged for a smaller or larger mask if required.

Eye or face protection

Worn when there is a risk from splashing of secretion (including respiratory secretions). Eye or face protection can be achieved using any one of:

  1. Surgical mask with integrated visor
  2. Full-face visor or shield
  3. Goggles
  4. Fluid-resistant (Type IIR) surgical face mask (FRSM)

The SARUS-CPR hood provides a see-through plastic barrier in order to visualise the patient which simultaneously creates a barrier to ejected small aerosols and larger droplets.

Face-mask seal

Surface contact seal achieved between an anaesthetic mask and the patients face during airway ventilation. A poor face-mask seal can result in aerosol generation and particle escape. Trials using the Resusi Anne model have confirmed that bag and mask ventilation using the SARUS-CPR hood is equivalent to standard CPR practice.
Clinical evaluation on volunteers has confirmed that an equivalent face-mask seal can be achieved when using the hood.

FFP function

Stands for ‘filtering face piece’. There are 3 categories of FFP respirator: FFP1, FFP2 and FFP3. FFP3 and loose-fitting powered hoods provide the highest level of protection and are recommended when caring for patients in areas where high risk aerosol generating procedures (AGPs) are being performed. The SARUS-CPR hood is believed to provide the equivalent of FFP3 protection to personnel.


Individuals who, as part of their CPR training and role, may provide immediate assistance to people who have collapsed as a consequence of cardiorespiratory arrest. The SARUS-CPR hood is designed to be used by personnel who have been trained in CPR ‘bag and mask’ ventilation. These people include health and social care staff, ambulance crews, rescue services, transportation services, first aiders and citizens trained to provide community CPR.

Fluid-resistant design

A term applied to fabrics that resist liquid penetration, often used interchangeably with ‘fluid-repellent’ when describing the properties of protective clothing or equipment. The SARUS-CPR hood has been designed by Keela, a company who produce high quality water-proof garments. Advanced textile seal technology is used in all of the device interfaces.

FRSM (Surgical mask)

A disposable ‘fluid-resistant surgical mask’ worn over the nose and mouth to protect the mucous membranes of the wearer’s nose and mouth from splashes and infectious droplets. FRSMs can also be used to protect patients. When recommended for infection control purposes a ‘surgical face mask’ typically denotes a fluid-resistant (Type IIR) surgical mask. When using the SARUS-CPR hood, personnel are encouraged to use surgical masks, plastic aprons, eye protection and gloves.

Frequently touched surfaces

Surfaces of the environment which are commonly touched or come into contact with human hands. The SARUS-CPR hood stops direct hand contact with the patients face and surfaces that might be contaminated with droplets, saliva and vomitus.

Guedel airway

An oropharyngeal airway (also known as an oral airway, OPA or Guedel pattern airway) is a medical device used to maintain or open a patient’s airway. It does this by preventing the tongue from covering the epiglottis, which could prevent the person from breathing. In ideal circumstances a Guedel airway should be inserted prior to using the SARUS-CPR hood.

Healthcare clinical waste

Waste produced as a result of healthcare activities, for example soiled clothing and bedding, masks and suction devices. The SARUS-CPR textile based hood contains the filter, mask and suction device, which are all disposed of as one unit.

Infectious linen and clothing

Linen and clothing that has been used by a patient who is known or suspected to be infectious and or linen that is contaminated with blood and or other body fluids. The SARUS-CPR hood provides a very effective barrier to the contact contamination of clothing and bedding by bodily fluids such as saliva, blood and large volumes of vomitus.

Neck closure: ‘tension stop control’ draw strings

The two draw strings that are tightened around the patients neck and released after use have been carefully designed to avoid overtightening. This is achieved through the careful selection of the elasticated cord / toggle interface and through the inclusion of knots in the cords, spaced at a set distance. These knots provide an absolute limit to the force of tightening that can be applied. Ultrasound research has confirmed that the trachea and carotid arteries are not affected by the draw strings. Venous return through internal jugular veins is reduced to about a quarter of normal flow.

Oral ‘Yankauer’ sucker

An oral suctioning tool used in medical procedures. It is typically a firm plastic suction tip with a large opening surrounded by a bulbous head and is designed to allow effective suction without damaging surrounding tissue. This tool is used to suction oropharyngeal secretions in order to prevent aspiration. A standard adult sized Yankauer sucker and attachments for suction tubing are incorporated in the SARUS-CPR hood.

Oxygen flows and concentration

100% concentration of oxygen is used during CPR, with flows usually greater than 6L/minute. High flow oxygen can safely be used together with the SARUS-CPR hood, introduced by connecting an oxygen supply to the hand-held ventilation bag. Oxygen flow should be temporarily discontinued prior to cardioversion.

Personal Protective Equipment (PPE)

Equipment a person wears to protect themselves from risks to their health or safety, including exposure to infection agents. This usually includes face (nose and mouth), eye, hands and body protection. The level of PPE required depends on the:

  1. Suspected or known infectious agent
  2. Severity of the illness caused
  3. Transmission route of the infectious agent
  4. Procedure or task being undertaken

The SARUS-CPR hood acts as PPE applied to the patient, providing immediate protection from aerosols, droplets, saliva, blood and vomitus. Once experienced CPR personnel arrive and are wearing full AGP PPE, first-responders are asked to step aside and allow the fully equipped team to remove and dispose of the hood, prior to possible intubation or supraglottic airway insertion.

RCUK (Resuscitation Council UK)

COVID-19 statements and resources: Resuscitation Council UK
RCUK: position on COVID-19 guidance in September 2020

Respiratory droplets

A small droplet, such as a particle of moisture released from the mouth during coughing, sneezing, or speaking. The SARUS-CPR hood creates a capsule around the patient, providing complete protection from droplets that are often coughed during patient recovery.

Respiratory protective equipment

Respiratory protection that is worn over the nose and mouth designed to protect the wearer from inhaling hazardous substances, including airborne particles (aerosols). There are 2 types of respiratory protection that can be used, tight-fitting disposable FFP respirators and loose-fitting powered hoods. FFP3 PPE masks are required by personnel undertaking CPR. The SARUS-CPR hood acts as an equivalent form of PPE, applied directly to the collapsed patient.

Risk Factor Protective Strategy

Organisational strategy in a healthcare context that is used to minimise risk to both patients, staff, finances and organisational reputation. The SARUS-CPR hood is a device which reduces the risks to collapsed patients and protects personnel from contamination and infection.


Physically separating or isolating from other people. The SARUS-CPR hood once deployed allows personnel to get closer to the patient and carry out the physical aspects of full CPR with more confidence.


Severe acute respiratory syndrome coronavirus, the virus responsible for the 2003 outbreak of human coronavirus disease. The SARUS-CPR hood affords protection from all viral and bacterial airborne and fluid transmitted infective diseases.


Severe acute respiratory syndrome coronavirus 2, the virus responsible for the COVID- 19 pandemic. The SARUS-CPR hood was designed in response to this pandemic, but in future will be used as part of normal CPR practice.


Standard Infection Protection Control Precautions. SICPs are the basic infection prevention and control measures necessary to reduce the risk of transmission of an infectious agent from both recognised and unrecognised sources of infection. For the purpose of CPR, the pathways and treatment undertaken should be treated as High risk. This will ensure that there is no delay to resuscitation and no increased risk to CPR personnel safety. The SARUS-CPR hood facilitates this fast, first patient response and protects personnel while awaiting the arrival of an experienced CPR team.


The SARUS-CPR hood is manufactured in a clean factory environment, producing a class 1 medical device that is packaged clean. It is not intended to be a sterile medical device.

Transmission based precautions

Additional precautions to be used in addition to SICPs when caring for patients with a known or suspected infection. These include the safety precautions required during patient transfer, handover between teams, decontamination of environments and disposal of contaminated equipment. The SARUS hood is for single use only and needs to be disposed of in clinical waste immediately after use.