An inadequate slip resistance of flooring and/or footwear may cause slipping accidents. Tripping is caused by uneven ground or obstacles on the surface or by poor coordination while walking. Slipping or tripping can cause falls. Such accidents are described as falls on the same level because they occur on level surfaces with no or little changes in inclination. Accidents in which a person falls from a roof or scaffold are not included within the category of slip, trip and fall accidents. Such accidents are classified as "falls from height".
Slips, trips and falls are a common cause of occupational accidents. In the EU 584,371 accidents at work occurred in 2019 due to Slipping - Stumbling and falling - Fall of persons of which 520 accidents were fatal . The data don't make a distinction between falls on the same level and falls from height, but it must be assumed that most of the fatal accidents fall into the category fall from height.
Among the non-fatal accidents, Slipping - Stumbling and falling - Fall of persons is the third most common cause after Loss of control (total or partial) of machine, means of transport or handling equipment, hand-held tool, object, animal and Body movement under or with physical stress (generally leading to an internal injury)  (figure 1).
A more detailed analysis of 1231 falls on the same level in the Netherlands  found that almost 40% of these falls are due to a loss of grip between the shoe and the floor surface, almost 30% are due to tripping over obstacles and about 15% to uncontrolled movements. Underlying causes include a lack of motivation and commitment, a lack of planning and procedures and inadequate equipment. The analysis also shows that older workers are more at risk of slipping or tripping accidents. 33% of the victims are older than 50 compared to only 19% for other types of accidents .
Based on the Framework Directive  employers must analyse workplace risks and take measures for improving safety and health at work. In addition, Directive 89/654 on workplace requirements  stipulates that employers must ensure that workplaces meet the safety requirements of annex I of the Directive. Requirements include that
- the floors of rooms must have no dangerous bumps, holes or slopes and must be fixed, stable and not slippery;
- when workers are employed at workstations outdoors, such workstations must as far as possible be arranged so that workers cannot slip or fall
Figure 1 – Causes of non-fatal accidents at work - % - (EU27-2019)
Source: figure compiled based on data from the Eurostat database - Accidents at work by sex, age, severity, NACE Rev. 2 activity and deviation (hsw_ph3_06) 
Factors affecting slip resistance
One of the main causes of slipping and tripping accidents is an inadequate slip resistance of flooring and footwear. Slip resistance can be defined as a 'measure of dynamic friction between two surfaces' . Slip resistance depends on the friction between flooring and shoe: the higher the friction, the higher the slip resistance. Several parameters influence frictional behaviour and thus slip resistance. These parameters can be classified into four broad categories: floor, shoe, contaminant and human factors.
1. A suitably selected and correctly installed floor may provide sufficient slip resistance irrespective of the footwear worn, and even when the floor surface is soiled or wet . In addition to the type of floor (such as ceramic tiles, natural stone, parquet, elastic surfacing), parameters such as the roughness, the profiling, the degree of wear and the state in which the floor is maintained affect slip resistance.
2. The footwear selected also has an influence upon the slip resistance. Important footwear parameters include the type of sole material, its hardness, elasticity, roughness, tread, and level of wear.
3. Liquid and solid contaminants increase the risk of slipping considerably, since they reduce the contact between shoe and floor. Typical examples are wet shoe soles, contamination by solids or liquids on the floor caused by production methods (spills), and condensation.
4. Human factors include parameters such as the walking behaviour, walking speed, weight, a person's physical fitness and attention, and also the ease with which slippery floors can be recognised as such.
Trip accidents are caused by uneven floor surfaces or obstructions in walkways. Trip hazards are usually low to the ground and not easily recognised. Common workplace trip hazards include uneven edges in flooring, steps, slopes, gutters and cracks, loose mats, open drawers, untidy tools, and/or electrical cords . Studies have shown that level changes of as little as 8 mm can pose a risk for the normal walking of fit healthy people. When tripping, the forward movement of the foot is suddenly stopped by an obstacle, such as a loose cable, but the body continues its forward movement. If a person fails to restore balance, they fall forward and may suffer injuries to the head, leg or wrist .
Falls on stairs pose a particular risk, especially if stairs are poorly designed. Design and construction failures that contribute in stair fall accidents include lack of handrails, insufficient tread depths and irregular riser heights. Descending stairs is more likely to result in a fall than ascending stairs .
The working environment can increase the risk of slip and trip accidents. Especially lighting is a key factor. Insufficient lighting levels but also inadequate lighting (e.g. uneven levels, contrasts, glare) can cause workers to slip or trip . Other environmental factors include temperature, weather conditions and visual or noise distractions.
Causes of slip and trip accidents can also be related to task characteristics (e.g. work pace, load carrying, walking distances, etc.) and work organisation (e.g. (lack of) maintenance programmes, work schedules and time constraints).
Individual characteristics such as age, visual impairment and a person's motor control ability to recover from imbalance  are also risk factors for slipping and tripping accidents. It should be noted that these individual characteristics can be influenced by task-related aspects such as wearing personal protective equipment (PPE) or exoskeletons. For instance, a study among firefighters found that the use of a self-contained breathing apparatus with or without face mask negatively affected balance . Exoskeletons, depending on their construction and weight, can restrict workers' natural freedom of movement, making it difficult to regain balance in the event of a fall .
Finally, risk perception and an individual's ability to identify any existing unsafe condition play a role. In fact, individuals tend to adjust their walking movements if they observe or expect hazardous conditions. For instance, people walking on icy floors will move more cautiously   . However, this ability can be affected by distractions such as obstructions or noise, fatigue and also by individual behaviour such as using a mobile phone or having a conversation .
Controlling the risks of slips, trips and falls, requires identifying the problem areas, assessing the risks, and deciding on the prevention measures. The EU legislative framework sets a hierarchy for preventive measures to be applied to prevent harm to workers. At the top of the hierarchy is eliminating the hazard at source.
Technical, organisational and individual measures can be taken to reduce slip and trip accidents.
Choosing appropriate flooring
Floors must be sufficiently slip-resistant, depending on the working characteristics and conditions. For example, a floor in a slaughterhouse requires higher slip resistance than a floor in a bank office. Flooring is a 'construction product' and falls within the scope of EU Regulation (305/2011) . The Regulation lays down conditions for the placing or making available on the market of construction products. One of the essential rules for construction products is that they must be designed and built in such a way that they do not present unacceptable risks of accidents or damage in service or in operation such as slipping or falling. In the framework of the Construction Product Regulation, harmonised standards serve as a link between the requirements of the Regulation by determining the performance of construction products, based on their characteristics and intended uses. The main standards for floors include:
- EN 14041 Resilient, textile and laminate floor coverings - Essential characteristics
- EN 14342 Wood flooring and parquet - Characteristics, evaluation of conformity and marking
- EN 14411 Ceramic tiles - Definition, classification, characteristics, assessment and verification of constancy of performance and marking
Layout of walkways
Walkways should be sufficiently wide and level. Thresholds, slopes and steps/ stairs should be avoided where possible.
Improving slip-resistance of existing floors
Shiny floors are often insufficiently slip-resistant and may require some form of remedial or improvement treatment. Chemical treatment in-situ of floors may be a suitable solution for existing mineral floor surfaces, such as natural stone floors, ceramic tiles, and concrete and screed floors. The chemical used to treat the floor (acid) reacts with the minerals and changes the roughness of the floor surface (acid-etching). Such treatment relies on the correct application of the etching product and often requires high concentrations posing serious health risks for those applying the product and bystanders   . Such solutions are not suitable for floors made of wood or artificial materials. Chemical treatment of floors in situ is worthwhile only if it enhances the slip resistance of the floor without significantly affecting its appearance or ease of cleaning. Other treatment methods are:
- mechanical treatment, e.g. grinding, sandblasting.
- thermal treatment: e.g. lasering, flame treatment .
Another way of improving the slip resistance of floor surfaces is applying slip-resistant tapes or sheets. They are available in various sizes and profiles.
Other technical measures
- installing appropriate lighting (e.g. good lighting levels, functioning and position of lights to ensure all floor areas are evenly lit);
- providing drainage in wet areas;
- securely fixing mats and carpets to the floor;
- providing slip-resistance mats at entrances for removing dirt;
- installing canopies above building entrances to shelter the outside of the door;
- preventing contamination of floors by installing exhausts on machinery, drip trays, etc.;
- installing floor heating;
- installing handrails on stairs;
- avoiding trailing electrical cords by installing additional power outlets, routing electrical cables in walls or ceilings or using cable covers to securely fix cables to surfaces.
Cleaning can help to reduce the likelihood of slip accidents by keeping floors free of contamination. However, cleaning often itself leads to surface contamination by water or a cleaning detergent. After cleaning, any improvement in slip resistance will not have its full effect until the surface has dried. It is recommended to test floor surfaces from time to time to check slip resistance and verify the effectiveness of the cleaning procedure.
The cleaning methods and products used must be suitable for the floor. In general, floors with a high slip resistance are also more difficult to clean. Cleaning machines with rotating brushes and jet streams have proved effective for the cleaning of floors with deep profiles or rough surfaces. Their use may pay off economically even on relatively small floor areas. When using jet-stream cleaning equipment it is important that the pressure and temperature of the liquid and the mixture ratio of the cleaning agent and water do not damage the floor and the joints.
Cleaning products should be used in accordance with the manufacturer's instructions. The correct concentration of products ensures their effectiveness. Dosing systems can help to reduce errors.
Other organisational measures
- organising housekeeping procedures for cleaning and maintenance;
- carrying out regular checks of floor surfaces;
- job design (avoiding carrying loads, reducing work pace, avoiding night work to reduce fatigue);
- organising supervision;
- implementing procedures on the immediate clean-up of spillages;
- implementing programmes such as 5S to keep workplaces tidy;
- setting up programmes motivating staff (awareness raising, behavioural based programmes, nudging);
- providing information and training;
- displaying warning/caution signs to mark trip hazards.
Suitable footwear plays a key role in preventing slip and trip incidents. For instance, a randomised controlled study in a population of workers from a food services company showed that providing slip-resistant footwear can be an effective intervention. The probability of a slipping injury was reduced significantly in the intervention group while in the control group slipping injuries increased  .
Tread patterns on shoe soles affect friction, especially when surfaces are contaminated with solid particles or liquid. A smooth sole may offer little slip resistance. Safety footwear placed on the European market must meet the requirements laid down in Regulation 2016/425/EU of 9 March 2016 on personal protective equipment . The presumption of conformity of PPE with the essential safety and health requirements of the Regulation, is confirmed by the use of harmonised European standards. Standard EN ISO 20345:2021 includes slip resistance as one of the basic requirements for safety footwear.
When selecting footwear, it's important to choose comfortable footwear that fits well and is easy to clean and maintain. Footwear should also be regularly checked and replaced if needed. Studies have shown that worn footwear affects the friction performance and increases the risk of injury from a slip and fall for the wearer .
Providing and maintaining appropriate PPE is an employer's obligation based on Directive 89/656/EEC of 30 November 1989 on the minimum health and safety requirements for the use by workers of personal protective equipment at the workplace . Before choosing slip-resistant footwear the employer should assess the risks and take into the nature of the job and workplace conditions. If possible, employers should organise tests of different types of footwear in the workplace and base the selection of the most appropriate footwear on user experiences. Consulting workers throughout the process of choosing slip-resistant footwear contributes to greater acceptance so that users are more likely to wear safety footwear effectively .
Slip, trip and fall accidents are one of the most common types of work-related injuries and remain a priority for employers and safety and health professionals. However, addressing these injuries can be challenging and preventive interventions in the workplace require a comprehensive approach based on technical, organisational and individual measures. Involving workers by setting up awareness and motivation programmes is a key success factor.
 Eurostat database - Accidents at work by sex, age, severity, NACE Rev. 2 activity and deviation (hsw_ph3_06) Available at: https://ec.europa.eu/eurostat/databrowser/explore/all/all_themes
 Rijksinstituut voor Volksgezondheid en Milieu. Lerenvoorveiligheid.nl. Val op gelijke hoogte. Available at: https://lerenvoorveiligheid.nl/val-op-gelijke-hoogte
 Directive 89/391/EEC of 12 June 1989 on the introduction of measures to encourage improvements in the safety and health of workers at work. Available at: https://osha.europa.eu/en/legislation/directives/the-osh-framework-directive/1
 Directive 89/654/EEC of 30 November 1989 concerning the minimum safety and health requirements for the workplace (first individual directive within the meaning of Article 16 (1) of Directive 89/391/EEC). Available at: https://osha.europa.eu/en/legislation/directives/2
 EN 16165:2021 Determination of slip resistance of pedestrian surfaces - Methods of evaluation.
 Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA). IFA test laboratory "Slip resistance of floor coverings". Available at: https://www.dguv.de/ifa/pruefung-zertifizierung/pruefung-von-bodenbelaegen/index-2.jsp
 EU-OSHA, E-fact 37 - Slips, trips, falls and cleaners. 2008. Available at: https://osha.europa.eu/en/publications/e-fact-37-slips-trips-falls-and-cleaners
 Atlas, R. What Is The Role Of Design And Architecture In Slip, Trip, And Fall Accidents? In Proceedings of the Human Factors and Ergonomics Society Annual Meeting, 2019, November, vol. 63, n°. 1, pp. 531-536. Available at: https://journals.sagepub.com/doi/abs/10.1177/1071181319631093
 Scott, A. Falls on Stairways – Literature Review. Report Number HSL/2005/10. Available at: https://www.hse.gov.uk/research/hsl_pdf/2005/hsl0510.pdf
 Carpenter, J., Lazarus, D., Perkins, C. Safer surfaces to walk on – reducing the risk of slipping. CIRIA, 2005, updated 2010.
 Antwi-Afari, M. F., Li, H., Seo, J., & Wong, A. Y. L. Automated detection and classification of construction workers' loss of balance events using wearable insole pressure sensors. Automation in Construction, 2018, 96, pp. 189-199. Available at: https://moticon.com/wp-content/uploads/2021/06/pdf-pub-clinical-063-Antwi-Afari-2018-Automated-detection-and-classification-of-construction-workers_-loss-of-balance-events-using-wearable-insole-pressure-sensors.pdf
 Brown, M. N., Char, R. M. M. L., Henry, S. O., Tanigawa, J., & Yasui, S. (2019). The effect of firefighter personal protective equipment on static and dynamic balance. Ergonomics, 62(9), 1193-1201. Available at: https://www.tandfonline.com/doi/abs/10.1080/00140139.2019.1623422
 EU-OSHA. The impact of using exoskeletons on occupational safety and health. Discussion paper, 2019. Available at: https://osha.europa.eu/en/publications/impact-using-exoskeletons-occupational-safety-and-health
 Chang, W-R., Leclercq, S., Lockhart, T.E, Haslam, R. State of science: occupational slips, trips and falls on the same level, Ergonomics, 2016, 59:7, pp. 861-883. Available at: https://doi.org/10.1080/00140139.2016.1157214
 Regulation (EU) No 305/2011 of 9 March 2011 laying down harmonised conditions for the marketing of construction products and repealing Council Directive 89/106/EEC. Available at: https://osha.europa.eu/en/legislation/directives/regulation-eu-no-305-2011-construction-products
 HSE. FAQ Slip resistance improvements. Available at: https://www.hse.gov.uk/slips/sat/faqslipimprove.htm
 Berufsgenossenschaft Handel und Warenlogistik. Fußböden Verbesserung der Rutschhemmung von Bodenbelägen. BGHW-Wissen, 2020. Available at: https://kompendium.bghw.de/bghw/xhtml/document.jsf?alias=bghw_wis_b12w51_1_1_
 EU-OSHA. Factsheet 14 - Preventing Work-Related Slips Trips and Falls. 2001. Available at: https://osha.europa.eu/en/publications/factsheet-14-preventing-work-related-slips-trips-and-falls
 Bell, J. L., Collins, J. W., & Chiou, S. Effectiveness of a no-cost-to-workers, slip-resistant footwear program for reducing slipping-related injuries in food service workers. Scandinavian journal of work, environment & health, 2019, 45(2), pp. 194-202. Available at: https://www.sjweh.fi/show_abstract.php?abstract_id=3790&fullText=1
 Regulation (EU) 2016/425 on personal protective equipment of the European Parliament and of the Council of 9 March 2016 on personal protective equipment and repealing Council Directive 89/686/EEC (with effect from 21 April 2018). Available at: https://osha.europa.eu/en/legislation/directive/regulation-eu-2016425-personal-protective-equipment
 Cook, A., Hemler, S., Sundaram, V., Chanda, A., Beschorner, K. Differences in Friction Performance between New and Worn Shoes, IISE Transactions on Occupational Ergonomics and Human Factors, 2020, 8:4, pp. 209-214. Available at https://doi.org/10.1080/24725838.2021.1925998
 Directive 89/656/EEC of 30 November 1989 on the minimum health and safety requirements for the use by workers of personal protective equipment at the workplace (third individual directive within the meaning of Article 16 (1) of Directive 89/391/EEC). Available at: https://osha.europa.eu/en/legislation/directives/4
 HSA. Choosing Slip-resistant Footwear - Information Sheet. 2017. Available at https://www.hsa.ie/eng/publications_and_forms/publications/slips_trips_and_falls/choosing_slip-resistant_footwear_-_information_sheet.html
EU-OSHA - European Agency for Safety and Health at Work, E-fact 37 - Slips, trips, falls and cleaners. 2008. Available at: https://osha.europa.eu/en/publications/e-fact-37-slips-trips-falls-and-cleaners
EU-OSHA - European Agency for Safety and Health at Work, EU-OSHA. Factsheet 14 - Preventing Work-Related Slips Trips and Falls. 2001. Available at: https://osha.europa.eu/en/publications/factsheet-14-preventing-work-related-slips-trips-and-falls
Napo in ... No laughing matter. Available at: https://www.napofilm.net/en/napos-films/napo-no-laughing-matter/napo-no-laughing-matter
INRS - Institut national de recherche et de sécurité pour la prévention des accidents du travail et des maladies professionnelles, Chutes de plain pied. Available at: https://www.inrs.fr/risques/chutes-de-plain-pied/ce-qu-il-faut-retenir.html
Institut für Arbeitsschutz der Deutschen Gesetzlichen Unfallversicherung (IFA). IFA test laboratory "Slip resistance of floor coverings". Available at: https://www.dguv.de/ifa/pruefung-zertifizierung/pruefung-von-bodenbelaegen/index-2.jsp
Berufsgenossenschaft Handel und Warenlogistik. Fußböden in Arbeitsbereichen mit Rutschgefahr, 2018. Available at: https://kompendium.bghw.de/bghw/xhtml/document.jsf?docId=bghw_kom/bghw_kom-Documents/b12m010/b12m010_0_.html
Eurosafe, European Association for Injury Prevention and Safety Promotion. Available at: https://www.eurosafe.eu.com/home