ANNEXU.K.
RISK ASSESSMENT GUIDELINES FOR CONSUMER PRODUCTS (1) U.K.
6. Examples U.K.
6.3. Sensitivity analysis U.K.
The factors used to calculate the risk of an injury scenario, namely the severity of the injury and the probability, often have to be estimated. This creates uncertainty. Probability in particular can be difficult to estimate, since the behaviour of consumers, for example, can be difficult to predict. Does a person perform a certain action often or only occasionally?
It is therefore important to consider the level of uncertainty of the two factors and to make a sensitivity analysis. The purpose of this analysis is to establish how much the risk level varies when the estimated factors vary. The example provided on the table below only shows the variation of probability, since the severity of the injury is usually predicted with more certainty.
A practical way of performing the sensitivity analysis is to repeat the risk assessment for a certain scenario, but to use a different probability for one or more steps in the scenario. For example, a candle containing seeds could cause a fire, because the seeds can catch fire and generate high flames. Furniture or curtains can catch fire and persons not in the room could inhale toxic fumes and suffer fatal poisoning:
| Injury scenario | Injury type and location | Severity of injury | Probability of injury | Resulting probability | Risk |
|---|---|---|---|---|---|
| Seeds or beans catch fire generating high flames. Furniture or curtains catch fire. Persons are not in room, but inhale toxic fumes. | Fatal poisoning | 4 |
| 0 00675 > 1/1 000 | Serious |
The probability levels for the steps in the scenario were estimated as shown in the table.
The overall probability is 0,00675, which corresponds to > 1/1 000 in table 4. This leads to the conclusion of ‘serious risk’. Note that the exact probability is closer to 1/100 than to 1/1 000, which already gives some confidence in the risk level because it is a little deeper in the serious risk area of table 4 than the > 1/1 000 row suggests.
Suppose we are uncertain about the 5 % probability that persons inhale the toxic fumes. We could put it at a much lower 0,1 % (0 001 = 1 in a thousand). If we recalculate with that assumption, the overall probability is 0,000135, which translates into > 1/10 000. Nevertheless, the risk is still serious. Even if for some reason the probability were to be a factor of 10 lower, the risk would still be high. Therefore, although the probability may vary 10- or 100-fold, we still find a serious or high risk (the latter being quite close to ‘serious’). Thus, this sensitivity analysis lets us confidently assess the risk as serious.
In general, however, risk assessment should be based on ‘reasonable worst cases’: not too pessimistic on every factor, but certainly not too optimistic.
Table 1
Consumers
| Consumers | Description |
|---|---|
| Very vulnerable consumers | Very young children: 0 to 36 months Others: Persons with extensive and complex disabilities |
| Vulnerable consumers | Young children: Children older than 36 months and younger than 8 years. Older children: Children 8 to 14 years Others: Persons with reduced physical, sensory or mental capabilities (e.g. partially disabled, elderly, including those over 65, with some reduction in their physical and mental capabilities), or lack of experience and knowledge |
| Other consumers | Consumers other than very vulnerable or vulnerable consumers |
Table 2
Hazards, typical injury scenarios and typical injuries
| NB: This table is for guidance only; the typical injury scenarios should be adapted when preparing a risk assessment. There is specific risk assessment guidance for chemicals, cosmetics and possibly others. It is highly recommended to use this specific guidance when assessing such products. See section 3.2. | |||
| Hazard group | Hazard(product property) | Typical injury scenario | Typical injury |
|---|---|---|---|
| Size, shape and surface | Product is obstacle | Person trips over product and falls; or person bumps into product | Bruising; fracture, concussion |
| Product is impermeable to air | Product covers mouth and/or nose of a person (typically a child), or covers internal airway | Suffocation | |
| Product is or contains small part | Person (child) swallows small part; the part gets stuck in larynx and blocks airways | Choking, internal airway obstruction | |
| Possible to bite off small part from product | Person (child) swallows small part; the part gets stuck in the digestive tract | Digestive tract obstruction | |
| Sharp corner or point | Person bumps into sharp corner or is hit by moving sharp object; this causes a puncture or penetration injury | Puncture; blinding, foreign body in eye; hearing, foreign body in ear | |
| Sharp edge | Person touches sharp edge; this lacerates the skin or cuts through tissues | Laceration, cut; amputation | |
| Slippery surface | Person walks on surface, slips and falls | Bruising; fracture, concussion | |
| Rough surface | Person slides along rough surface; this causes friction and/or abrasion | Abrasion | |
| Gap or opening between parts | Person puts a limb or body in opening and finger, arm, neck, head, body or clothing is trapped; injury occurs due to gravity or movement | Crushing, fracture, amputation, strangulation | |
| Potential energy | Low mechanical stability | Product tips; person on top of product falls from height, or person near product is hit by the product; electrical product tips, breaks and gives access to live parts, or continues to work heating nearby surfaces | Bruising; dislocation; sprain; fracture, concussion; crushing; electric shock; burns |
| Low mechanical strength | Product collapses by overloading; person on top of product falls from height, or person near product is hit by the product; electrical product tips, breaks and gives access to live parts, or continues to work heating nearby surfaces | Bruising; dislocation; fracture, concussion; crushing; electric shock; burns | |
| High position of user | Person at high position on the product loses balance, has no support to hold on to and falls from height | Bruising; dislocation; fracture, concussion; crushing | |
| Elastic element or spring | Elastic element or spring under tension is suddenly released; person in the line of movement is hit by the product | Bruising; dislocation; fracture, concussion; crushing | |
| Pressurised liquid or gas, or vacuum | Liquid or gas under pressure is suddenly released; person in the vicinity is hit; or implosion of the product produces flying objects | Dislocation; fracture, concussion; crushing; cuts (see also under fire and explosion) | |
| Kinetic Energy | Moving product | Person in the line of movement of the product is hit by the product or run over | Bruising; sprain; fracture, concussion; crushing |
| Parts moving against one another | Person puts a body part between the moving parts while they move together; the body part gets trapped and put under pressure (crushed) | Bruising; dislocation; fracture; crushing | |
| Parts moving past one another | Person puts a body part between the moving parts while they move close by (scissor movement); the body part gets trapped between the moving parts and put under pressure (shearing) | Laceration, cut; amputation | |
| Rotating parts | A body part, hair or clothing of a person is entangled by the rotating part; this causes a pulling force | Bruising; fracture; laceration (skin of the head); strangulation | |
| Rotating parts close to one another | A body part, hair or clothing of a person is drawn in by the rotating parts; this causes a pulling force and pressure on the body part | Crushing, fracture, amputation, strangulation | |
| Acceleration | Person on the accelerating product loses balance, has no support to hold on to and falls with some speed | Dislocation; fracture, concussion; crushing | |
| Flying objects | Person is hit by the flying object and depending on the energy sustains injuries | Bruising; dislocation; fracture, concussion; crushing | |
| Vibration | Person holding the product loses balance and falls; or prolonged contact with vibrating product causes neurological disorders, osteoarticular disorder, trauma of the spine, vascular disorder | Bruising; dislocation; fracture; crushing | |
| Noise | Person is exposed to noise from the product. Tinnitus and hearing loss may occur depending on sound level and distance | Hearing injury | |
| Electrical Energy | High/low voltage | Person touches part of the product that is at high voltage; the person receives an electric shock and may be electrocuted | Electric shock |
| Heat production | Product becomes hot; a person touching it may sustain burns; or the product may emit molten particles, steam, etc., that hits a person | Burn, scald | |
| Live parts too close | Electric arc or sparks occur between the live parts. This may cause a fire and intense radiation | Eye injury; burn, scald | |
| Extreme temperatures | Open flames | A person near the flames may sustain burns, possibly after clothing catches fire | Burn, scald |
| Hot surfaces | Person does not recognise the hot surface and touches it; the person sustains burns | Burn | |
| Hot liquids | Person handling a container of liquid spills some of it; the liquid falls on the skin and causes scalds | Scald | |
| Hot gases | Person breathes in the hot gases emitted from a product; this causes lung burn; or prolonged exposure to hot air causes dehydration | Burn | |
| Cold surfaces | Person does not recognise the cold surface and touches it; the person sustains frostbite | Burn | |
| Radiation | Ultraviolet radiation, laser | Skin or eyes of a person are exposed to radiation emitted by the product | Burn, scald; neurological disorders; eye injury; skin cancer, mutation |
| High intensity electromagnetic field (EMF) source; low frequency or high frequency (microwave) | Person is close to the electromagnetic field (EMF) source, body (central nervous system) is exposed | Neurological (brain) damage, leukaemia (children) | |
| Fire and explosion | Flammable sub stances | Person is near the flammable substance; an ignition source sets the substance on fire; this causes injuries to the person | Burn |
| Explosive mixtures | Person is near the explosive mixture; an ignition source causes an explosion; the person is hit by the shock wave, burning material and/or flames | Burn, scald; eye injury, foreign body in eye; hearing injury, foreign body in ear | |
| Ignition sources | The ignition source causes a fire; a person is injured by flames, or intoxicated by gases from the house fire | Burn; poisoning | |
| Overheating | Product overheats; fire, explosion | Burn, scald; eye injury, foreign body in eye; hearing injury, foreign body in ear | |
| Toxicity | Toxic solid or fluid | Person ingests substance from product, e.g. by putting it in mouth, and/or substance gets on skin | Acute poisoning; irritation, dermatitis |
| Person breathes in solid or fluid, for example vomited material (pulmonary aspiration) | Acute poisoning in lungs (aspiration pneumonia); infection | ||
| Toxic gas, vapour or dust | Person inhales substance from product; and/or substance gets on skin | Acute poisoning in lungs; irritation, dermatitis | |
| Sensitising substance | Person ingests substance from product, e.g. by putting it in mouth; and/or substance gets on skin; and/or person inhales gas, vapour or dust | Sensitisation; allergic reaction | |
| Irritating or corrosive solid or fluid | Person ingests substance from product, e.g. by putting it in mouth, and/or substance gets on skin or in eyes | Irritation, dermatitis; skin burn; eye injury, foreign body in eye | |
| Irritating or corrosive gas or vapour | Person inhales substance from product, and/or substance gets on skin or in eyes | Irritation, dermatitis; skin burn; acute poisoning or corrosive effect in lungs or in eyes | |
| CMR substance | Person ingests substance from product, e.g. by putting it in mouth, and/or substance gets onto skin; and/or person inhales substance as gas, vapour or dust | Cancer, mutation, reproductive toxicity | |
| Microbiological contamination | Microbiological contamination | Person gets into contact with contaminated product by ingestion, inhalation or skin contact | Infection, local or systemic |
| Product operating hazards | Unhealthy posture | Design causes unhealthy posture of person when operating the product | Strain; musculoskeletal disorder |
| Overexertion | Design requires use of considerable force when operating the product | Sprain or strain; musculoskeletal disorder | |
| Anatomical unsuitability | Design is not adapted to human anatomy, which makes it difficult or impossible to operate | Sprain or strain | |
| Ignoring personal protection | Design makes it difficult for a person wearing protection to handle or operate the product | Various injuries | |
| Inadvertent (de)activation | Person can easily (de)activate product, which leads to unwanted operation | Various injuries | |
| Operational inadequacy | Design provokes faulty operation by a person; or product with a protective function does not provide expected protection | Various injuries | |
| Failure to stop | Person wants to stop the product, but it continues to operate in situation where this is unwanted | Various injuries | |
| Unexpected start | Product shuts down during a power failure, but resumes operation in a hazardous way | Various injuries | |
| Inability to stop | In an emergency situation, person is not able to stop operation of the product | Various injuries | |
| Inadequately fitting parts | Person tries to fit a part, needs too much force to fit, product breaks; or part is too loosely fitted and becomes loose during use | Sprain or strain; laceration, cut; bruising; entrapment | |
| Missing or incorrectly fitted protection | Hazardous parts are reachable for a per son | Various injuries | |
| Insufficient warning instructions, signs and symbols | User does not notice warning instructions signs and/or does not understand symbols | Various injuries | |
| Insufficient warning signals | User does not see or hear warning signal (optical or audio), causing dangerous operation | Various injuries | |
Table 3 Severity of injury U.K.
IntroductionU.K.
These risk assessment guidelines distinguish between four levels of injury harm severity. It is important to realise that severity should be assessed completely objectively. The aim is to compare the severity of different scenarios and to set priorities, not to judge the acceptability of a single injury at this stage. Any injury harm that could easily have been avoided will be difficult to accept for a consumer. However, authorities can justifiably invest more effort into avoiding irreversible consequences than into preventing temporary discomfort.
In order to assess the severity of the consequences (acute injury or other damage to health), objective criteria can be found, on the one hand, in the level of medical intervention, and, on the other hand, in the consequences to the further functioning of the victim. Both could be expressed as cost, but the costs of consequences of health damage may be difficult to quantify.
Combining these criteria, the four levels may be defined as follows:
Harm or consequence that after basic treatment (first aid, normally not by a doctor) does not substantially hamper functioning or cause excessive pain; usually the consequences are completely reversible.
Harm or consequence for which a visit to A&E may be necessary, but in general, hospitalisation is not required. Functioning may be affected for a limited period, not more than about 6 months, and recovery is more or less complete.
Harm or consequence that normally requires hospitalisation and will affect functioning for more than 6 months or lead to a permanent loss of function.
Harm or consequence that is or could be fatal, including brain death; consequences that affect reproduction or offspring; severe loss of limbs and/or function, leading to more than approximately 10 % of disability.
The following table, which should be considered as a guide rather than prescriptive or complete, provides examples of injuries at all four levels. National differences may exist, either cultural or caused by different systems of health care and financial arrangements. However, deviating from the proposed classification in the table will affect uniform assessment of risks in the EU; this should be clearly stated and explained in the risk assessment report, and reasons should be given.
| Type of injury | Severity of injury | |||
|---|---|---|---|---|
| 1 | 2 | 3 | 4 | |
| Laceration, cut | Superficial | External (deep) (> 10 cm long on body) (> 5 cm long on face) requiring stitches Tendon or into joint White of eye or cornea | Optic nerve Neck artery Trachea Internal organs | Bronchial tube Oesophagus Aorta Spinal cord (low) Deep laceration of internal organs Severed high spinal cord Brain (severe lesion/ dysfunction) |
| Bruising (abrasion/ contusion, swelling, oedema) | Superficial ≤ 25 cm2 on face ≤ 50 cm2 on body | Major > 25 cm2 on face > 50 cm2 on body | Trachea Internal organs (minor) Heart Brain Lung, with blood or air in chest | Brain stem Spinal cord causing paralysis |
| Concussion | — | Very short unconsciousness (minutes) | Prolonged unconsciousness | Coma |
| Entrapment/ pinching | Minor pinching | — | (Use as appropriate the final outcomes of bruising, crushing, fracture, dislocation, amputation, as applicable.) | (Same outcome as for suffocation/ strangulation.) |
| Sprain, strain, musculoskeletal disorder | Extremities Joints Spine (no dislocation or fracture) | Knee ligaments strain | Ligament or tendon rupture/tear Muscle tear Whiplash | — |
| Dislocation | — | Extremities (finger, toe, hand, foot) Elbow Jaw Loosening of tooth | Ankle Wrist Shoulder Hip Knee Spine | Spinal column |
| Fracture | — | Extremities (finger, toe, hand, foot) Wrist Arm Rib Sternum Nose Tooth Jaw Bones around eye | Ankle Leg (femur and lower leg) Hip Thigh Skull Spine (minor compression fracture) Jaw (severe) Larynx Multiple rib fractures Blood or air in chest | Neck Spinal column |
| Crushing | — | — | Extremities (fingers, toe, hand, foot) Elbow Ankle Wrist Forearm Leg Shoulder Trachea Larynx Pelvis | Spinal cord Mid-low neck Chest (massive crushing) Brain stem |
| Amputation | — | — | Finger(s) Toe(s) Hand Foot (Part of) Arm Leg Eye | Both extremities |
| Piercing, puncturing | Limited depth, only skin involved | Deeper than skin Abdominal wall (no organ involvement) | Eye Internal organs Chest wall | Aorta Heart Bronchial tube Deep injuries in organs (liver, kidney, bowel, etc.) |
| Ingestion | — | — | Internal organ injury (Refer also to internal airway obstruction where the ingested object gets stuck high in the oesophagus.) | Permanent damage to internal organ |
| Internal air way obstruction | — | — | Oxygen flow to brain blocked without permanent consequences | Oxygen flow to brain blocked with permanent consequences |
| Suffocation/ Strangulation | — | — | Oxygen flow to brain blocked without permanent consequences | Fatal suffocation/ strangulation |
| Submersion/ Drowning | — | — | — | Fatal drowning |
| Burn/Scald (by heat, cold, or chemical substance) | 1°, up to 100 % of body surface 2°, < 6 % of body surface | 2°, 6-15 % of body surface | 2°, 16-35 % of body surface, or 3°, up to 35 % of body surface Inhalation burn | 2° or 3°, > 35 % of body surface Inhalation burn requiring respiratory assistance |
| Electric shock | (See also under burns as electric current can cause burns.) | Local effects (temporary cramp or muscle paralysis) | — | Electrocution |
| Neurological disorders | — | — | Triggered epileptic seizure | — |
| Eye injury, foreign body in eye | Temporary pain in eye without need for treatment | Temporary loss of sight | Partial loss of sight Permanent loss of sight (one eye) | Permanent loss of sight (both eyes) |
| Hearing injury, foreign body in ear | Temporary pain in ear without need for treatment | Temporary impairment of hearing | Partial loss of hearing Complete loss of hearing (one ear) | Complete loss of hearing (both ears) |
| Poisoning from substances (ingestion, inhalation, dermal) | Diarrhoea, vomiting, local symptoms | Reversible damage to internal organs, e.g. liver, kidney, slight haemolytic anaemia | Irreversible damage to internal organs, e.g. oesophagus, stomach, liver, kidney, haemolytic anaemia, reversible damage to nerve system | Irreversible damage to nerve system Fatality |
| Irritation, dermatitis, inflammation or corrosive effect of substances (inhalation, dermal) | Local slight irritation | Reversible eye damage Reversible systemic effects Inflammatory effects | Lungs, respiratory insufficiency, chemical pneumonia Irreversible systemic effects Partial loss of sight Corrosive effects | Lungs, requiring respiratory assistance Asphyxia |
| Allergic reaction or sensitisation | Mild or local allergic reaction | Allergic reaction, widespread allergic contact dermatitis | Strong sensitisation, provoking allergies to multiple substances | Anaphylactic reaction, shock Fatality |
| Long-term damage from contact with substances or from exposure to radiation | Diarrhoea, vomiting, local symptoms | Reversible damage to internal organs, e.g. liver, kidney, slight haemolytic anaemia | Damage to nervous system, e.g. Organic Psycho Syndrome (OPS; also called Chronic Toxic Encephalopathy, also known as ‘painters' disease’). Irreversible damage to internal organs, e.g. oesophagus, stomach, liver, kidney, haemolytic anaemia, reversible damage to nervous system | Cancer (leukaemia) Effects on reproduction Effects on offspring CNS depression |
| Microbiological infection | Reversible damage | Irreversible effects | Infection requiring prolonged hospitalisation, antibiotics-resistant organisms Fatality | |
Table 4
Risk level from the combination of the severity of injury and probability
| Probability of damage during foreseeable lifetime of the product | Severity of injury | ||||
|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | ||
| High  Low | >50 % | H | S | S | S |
| > 1/10 | M | S | S | S | |
| > 1/100 | M | S | S | S | |
| > 1/1 000 | L | H | S | S | |
| > 1/10 000 | L | M | H | S | |
| > 1/100 000 | L | L | M | H | |
| > 1/1 000 000 | L | L | L | M | |
| < 1/1 000 000 | L | L | L | L | |
S — Serious RiskU.K.
H — High risk
M — Medium risk
L — Low risk
Glossary of termsU.K.
:
Source of danger involving the chance of being injured or harmed. A means of quantifying the hazard in a risk assessment is the severity of the possible injury or harm.
:
Hazard created by the properties of a product.
:
Balanced combination of a hazard and the probability that damage will occur. Risk describes neither the hazard, nor the probability, but both at the same time.
:
Procedure for identifying and assessing hazards, consisting of three steps:
identification of the seriousness of a hazard;
determination of the probability that a consumer will be injured by that hazard;
combination of the hazard with the probability.
:
Degree of risk, which may be ‘serious’, ‘high’, ‘medium’ and ‘low’. When the (highest) level of risk has been identified, the risk assessment is complete.
:
Follow-up action, which is separate from risk assessment and aims to reduce or eliminate a risk.
If you need more information on the Risk Assessment method for harmonised products (both consumer and professional products) in relation to broader categories of public risks protected under EU harmonisation legislation, please refer to Part I, Chapter 5.3.