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Stair design specifications for older adults or for people with limited mobility:
This article lists safety features and optimal stairway designs for older building occupants. These same specifications should assist anyone who has limited ability to climb stairs such as people suffering from arthritis.
Optimum Stair Riser Height for Seniors & People with Limited Stair Climbing Ability
This article discusses stair step designs for people who have trouble ascending or descending stairways.
What about building long stair runs with steps each of which has a very low riser height? Here we discuss stair options for easy-climbing stairs and we point out where some low-riser step hazards may be lurking along the stairway.
Stair falls are particularly dangerous for the elderly or for others with limited mobility. But does this mean that we should simply eliminate stairs, replacing them with ramps or stairway chair lifts?
But there are also health benefits from using stairs, leading expert sources to avoid recommending simply stopping using stairways as we illustrate with the following excerpt from the Canadian Mortgage and Housing Corporation.
Falls on stairs can be a major threat to health, independence and confidence. The physical consequences can be serious, including soft-tissue damage and broken bones — especially hips. Other serious consequences — particularly for older people — can be the psychological effects resulting from a fall such as lowered confidence and a loss of a feeling of safety, which further reduces health, mobility and activity. Many people never fully recover from the consequences of a fall. ...
There can be health benefits to using stairs. According to Health Canada’s Stairway to Health Program, activities like climbing stairs significantly contribute to the 30 minutes of physical activity we all need every day. Stair climbing increases leg power and may be important in helping elderly people reduce the risk of injury from falls.
Your doctor can best advise you if you have special health problems that might limit or even prevent you from using stairs. However, it does mean always being aware that stairs can be risky and knowing how to reduce the risks. - CMHC (2015)
Reader Question: what are the best stair dimensions for people with physical limitations or for seniors
28 April 2015 Cynthia Johnson said:
What are the best dimensions for seniors with physical limitations i.e. Rheumatoid Arthritis?
Excellent question, Cynthia. Experts suggest that for more physically limited people the best way avoid falls is to seek living accommodations on a single floor.
Affi et als (2014 and earlier) have weighted the contributions of various stair features to the risk of a stair fall, considering for example, straight versus turned stairways, with or without landings, number of steps, handrail design, lighting specifications, and step design specifications (using a tread depth of 269mm and a riser height of 174mm with a 40 mm tread nosing in a case example to state various risk contributors. Afifi et als (2013 & 2014) specifically investigated staircase design for older adults.
Best step riser height for seniors
The authors examined riser heights between 152mm (5.98 in) and 190 mm (7.48 in). These riser heights or "step rise heights" appear to be the optimal range in riser height.
Best going depth or tread depth for stair treads for seniors
The "going depth" or "tread depth" which I describe as distance from stair nose face to riser face was considered optimal at 280 mm to 330 mm. The authors cited < 280mm and > 330 mm as "worst-case" scenarios, but I suggest that for some situations such as exterior stairs where much long going depths are feasible those data might change.
For an interior stairway, very long going depth dimensions are not practical because the total stair run becomes longer than will fit in most indoor spaces. Furthermore the cost of converting an existing set of steps each having a 7-inch rise into a set of stair steps each with a 3.5" rise would not only double the run length of the stairway but it would be very costly. In some cases low-rise steps with intermediate landing platforms might fit into a building space but again, the cost of such a change is probably much greater than the addition of a stairway chair lift.
Interestingly, recent research by Donath et als (2013) suggests that stair climbing can make an important contribution to the health, fitness, balance and heart condition of seniors.
Beyond that I've seen with my own mom as well as in the literature, that the smallest irregularity in a walking surface, more than about 1/8", can form a trip and fall hazard. Indeed falls the major source of injuries in most countries (though traffic accidents claim more lives) and the major source of lost work time among the working population. Gunatilaka (2005) in recommending stair code improvements for Australia, focused on falls in the home and found falls causing 16% of all unintentional deaths (2002) and 23% of hospital admissions.
Critical factors in safe stair design for seniors or people with limited mobility
Beginning at STAIR DIMENSIONS, WIDTH, HEIGHT we describe stair codes, construction, and design specifications. But Affi et als in a recent work (2014) cite an exhaustive if not exhausting list of stair features that are considered in assessing the safety of a stairway, from which we excerpt and adapt for cases where stairs are unavoidable and we are trying to both make stairs easy to climb and to minimize trip hazards we want first to pay attention to the following items.
Geometric design of the stairway: stair shape (straight vs circular or composite, number of steps per flight). Stair cases may be straight, U-shaped, curved or spiral (in my opinion high risk because of irregular tread shape and reduced walking area as well as sometimes forcing a user to walk away from a handrail) or making a partial or complete turn; landings may be present or omitted.
Number of steps in the stairway: both long stair flights (more than 12 steps) and short stair flights (less than 6 steps) increase the risk of falling.
Optimal is 10-12 steps in the stair flight. Afifi (2014).
Stairway lighting: proper lighting in the stairways is not only required in all model building codes, but is critical for elder-safety. Illumination of stairways used by older people should be at least 300-lux according to the Illuminating Engineering Society of North America (IESNA) and illumination must be consistent. The proper location of light switches is also very important.
Switches must be located far enough from the stairway as to be safely accessible and must be able to turn lights on and off from both stair top and bottom (as is required by stair codes). See Kim (2009)
See LIGHTING OVER STAIRS & AT EXITS
Handrailing design: secure, continuous, graspable handrailings, at the proper height.
Optimal handrailing height is 910mm (35.8 in) - 970 mm (38.2 in)
Rail texture may also be a factor in graspability, and clearance distance between rail and wall is important as is the presence of (usually code-specified) rail extensions. If the stairway width allows, provide handrailings on both sides of the stairway. Afifi assigns the following fall-safety rating factors where higher numbers are safer:
Handrailing on both sides of the stairway, R=1.00
Handrailing on one side of the stairway, R=0.67
Handrailing is missing, R=0.00
Clear visual cues of changes in walking surface help avoid trip hazards by making the presence of steps between rooms very apparent.
With those basics in place, if people using a stair have trouble with tall treads we could, if space permits, use a shorter rise, even just 3-inches. BUT to do so every stair tread also has to be made longer (or "deeper" in the direction of travel). That is, we can't shorten the rise without making the tread depth greater as well. Otherwise the stairs are still a trip hazard.
A lot of research has been done into optimal stair tread design. Interestingly the optimum stair design for ascending can be different from descending, so every stair design will have to compromise those theories.
Research on Easily-Climbable Stairs: optimal stair design for seniors or physically-limited building occupants
U.S. ADA Stair & Railing Specifications vs Easy-Climbing Stairs
There you will see that the ADA section 4.9 "Stairs" does not discuss short riser stair steps or "easily-climbable stairs".
"2010 ADA Standards for Accessible Design", U.S. Americans with Disabilities Act, 1990, U.S. Department of Justice, & revised Title II & Title III 2010, Website: www.ada.gov, Tel: 1-800-514-0301, TTY: 1-800-514-0383
ELDERLY & VETERANS HOME SAFETY - home safety & security checklist & home safety for older occupants. Home safety advice for the disabled and for veterans. Definition of Aging In Place systems and support for the elderly. Sources of home monitoring systems for the elderly. Sources of medication reminder and prescription refill services for the elderly. Sources of inspectors for home safety inspections. Sources of financing for home safety and accessibility improvements
SLIP TRIP & FALL HAZARD LIST, STAIRS - Photographs of all kinds of stair and step & walk defects illustrate a wide range of causes of falling down the stairs - stair trip and fall hazards and injury sources. Worn, Loose, Damaged Steps & Stair Fall Hazards. Narrow Tall Stair Steps, Slippery Stair Tread Surfaces. Curved, Angled, & Winder Stair Trip Hazards. Discontinuous, Awkward, Stairs & Steps. Curved, Tapered Steps & Stair Hazards. Lack of Visual clues to Indicate Presence of a Step or Stair. Is it a Step or a Passage? A rug at the top of the stairs is a fall hazard.
SLIPS, TRIPS & FALLS, EXTERIOR STAIRS - Exterior Stair trip & fall hazard photographs & descriptions - a photo catalog of slip trip and fall hazards at outdoor steps and stairs. Dilapidated Stair Structures: rot, loose connections, pitched, wobbly, missing parts, collapse risk. Unsafe Landscape-tie or railroad tie step and walk tripping hazards. Slip Trip Fall Defects in Masonry Steps and Landings Outdoors. Slippery Exterior Stair Surfaces: glass & tile. Curved, Tall, or Uneven Stair Fall Hazards. Clandestine Trip and Fall Hazards at Low Decks & Platforms. Algae, Ice, Fungus, & Other Stair Slip, Trip & Fall Hazards
Afifi, Mona, Belinda Parke, and Mohamed Al-Hussein. "Integrated approach for older adult friendly home staircase architectural design." Automation in Construction 39 (2014): 117-125.
Abstract The older adult population requires special consideration in terms of interior architectural design. This paper presents a methodology which aims to investigate the risk of falling associated with the architectural design of staircase elements, in order to suggest best practices to create elderly-friendly design that enhances safety for older adults. The proposed methodology uses the concept of evidence-based assessment to evaluate staircase elements such as handrail and step design.
This paper also presents a scenario-based rating system that assesses the degree of the risk of falling for different types of architectural staircase design. The proposed rating system was incorporated into a mathematical model and a Design Assessment Tree (DAT) that calculate the degree of risk associated with architectural staircase design to facilitate a building information modeling (BIM) approach. A hypothetical case study is presented to illustrate the effectiveness of the proposed methodology and highlights the essential features of the proposed model.
Afifi, Mona, Belinda Parke, and Mohamed Al-Hussein. "Evidence-Based Assessment of Geometrical Staircase Configurations for Older Adults." In AEI 2013 @ Building Solutions for Architectural Engineering, pp. 584-593. ASCE. [AEI Architectural Engineering Institute (AEI)
Abstract: Maintaining safety for older adults aged 65 years and older is a challenge that could be addressed by applying conscious design. Accordingly, the concept of creating a home environment which enhances safety for older adults becomes essential. Considering that staircases vary widely in their geometrical configurations, this paper presents an evidence-based assessment for geometrical staircase configurations from the perspective of reducing the risk of falling for older adults. The methodology is divided into two stages: 1) identifying the most common geometrical home staircase configurations, which include U-shape stairs, quarter turn stairs, straight stairs with landing, straight stairs without landing, helical stairs, spiral stairs, and composite stairs;
2) investigating the associated risk of falling for each geometrical staircase configuration through developing an evidence-based comparison for the proposed geometrical staircase configurations.
The output of this paper is a hierarchical listing for geometrical staircase configurations which is arranged from lowest to highest reduction in risk of falling for older adults.
Canada Mortgage and Housing Corporation CMHC, "Preventing Falls on Stairs", retrieved 28 April 2015, original source: http://www.cmhc-schl.gc.ca/en/co/acho/acho_012.cfm
Donath, L., O. Faude, R. Roth, and L. Zahner. "Effects of stair‐climbing on balance, gait, strength, resting heart rate, and submaximal endurance in healthy seniors." Scandinavian journal of medicine & science in sports 24, no. 2 (2014): e93-e101.
Abstract Excerpt: With more pronounced effects in INT2, stair-climbing significantly improved resting and exercise heart rates, perceived exertion, and dynamic balance performance in healthy seniors and may contribute to better overall fitness, reduced fall risk, and less perceived strain during daily life activities.
Gunatilaka, Ajith, Angela Clapperton, and Erin Cassell. "Preventing home fall injuries: structural and design issues and solutions." Hazards 59 (2005): 1-17.
Irvine, C. H., S. H. Snook, and J. H. Sparshatt. "Stairway risers and treads: acceptable and preferred dimensions." Applied Ergonomics 21, no. 3 (1990): 215-225.
Abstract Stairway preference and acceptability were investigated with psychophysical techniques. A series of six experiments was conducted where subjects ascended and descended 19 sets of stairways with different riser and tread (run) dimensions. Subjects were instructed to identify stairways that they considered acceptable, and the one stairway they most preferred. The optimum riser was 7·2 in (183 mm), and the optimum tread (run) was 11 or 12 in (279 or 300 mm). These dimensions were acceptable to both males and females, young and old, and subjects of greater or lesser stature. Larger dimensions were not as acceptable to shorter subjects, and smaller dimensions were not as acceptable to taller subjects. The 4-in (102 mm) riser was almost totally unacceptable, and never preferred. The 5·14 and 9-in (131 and 229 mm) risers were acceptable to less than one-third of the subjects, and rarely or never preferred. These results are compared with existing practices and recommendations.
Jackson, Patricia L., and H. Harvey Cohen. "An in-depth investigation of 40 stairway accidents and the stair safety literature." Journal of Safety Research 26, no. 3 (1995): 151-159.
Abstract Each year thousands of people trip, stumble, and/or fall on stairs. This paper reviews prominent literature on stairway safety, and discusses findings from a preliminary survey of 40 in-depth stair accident cases. Variables reviewed and discussed include personal/demographic, external, and dimensional. From these findings and those of other researchers, it is hypothesized that the greatest problem with accident stairways is not individual (i.e., user) or external variables, but dimensional inconsistency inherent in some stairways. Areas for future research are also discussed.
Kerr, Jacqueline, Jordan A. Carlson, James F. Sallis, Dori Rosenberg, Chikarlo R. Leak, Brian E. Saelens, James E. Chapman et al. "Assessing health-related resources in senior living residences." Journal of Aging Studies 25, no. 3 (2011): 206-214.
Kim, B. J. "Prevention of falls during stairway descent in older adults." Applied ergonomics 40, no. 3 (2009): 348-352.
Abstract A prospective design was applied to examine how older adults would adapt stairway intervention stimuli to gait patterns during stairway descent to prevent falls. Ambient lighting and an auditory signal were used as stairway intervention stimuli. The gait pattern changes with and without stimuli were compared. No significant change of angular displacement was found between normal condition and intervention conditions under daylight and nightlight. The lighting intervention tended to increase the knee's angular velocity for both daylight and nightlight conditions, but not the ankle's angular velocity. However, adding the auditory signal to the lighting intervention under nightlight condition increased the ankle's angular velocity. Under the daylight condition, every intervention was significantly helpful to make people step on the floor more confidently compared to the condition without interventions. However, the intervention of lighting had an opposite effect on the confidence of stepping under the nightlight condition. The intervention of lighting may contribute to increase of confidence during stair descent while compromising the declined stride length in older adults and the potential “rush” factor for falls on stairs.
Kose, Satoshi. "Housing for an Ageing Society: Adapting Housing Design toward Universality is the Minimum Requirement for Inclusion." In Aging, Disability and Independence: Selected Papers from the 4 th International Conference on Aging, Disability and Independence, pp. 19-39. 2008.
Livingston, Lori A., Joan M. Stevenson, and Sandra J. Olney. "Stairclimbing kinematics on stairs of differing dimensions." Arch Phys Med Rehabil 72, no. 6 (1991): 398-402.
Lockwood, Ian M., and John P. Braaksma. "Foot accommodation on various stair tread sizes." Journal of Architectural and Planning Research (1990): 1-12.
Abstract: This study investigates the effects of changing the tread length of stairs with regards to several foot placement measurements. The experiment utilized a helical staircase to create tread lengths varying from 203.2 mm (8") to 279.4 mm (11") with a constant riser height of 177.8 mm (7"). Six test subjects descended each of the four different tread lengths at three different speeds and wearing various types of footwear. The results were obtained through analysis of data obtained by filming the experiment and using digitizing techniques.
Marsh, Anthony P., W. Jack Rejeski, Wei Lang, Michael E. Miller, and Stephen P. Messier. "Baseline balance and functional decline in older adults with knee pain: the Observational Arthritis Study in Seniors." Journal of the American Geriatrics Society 51, no. 3 (2003): 331-339.
Templer, John, John Archea, and H. Harveoy Chen. "Study of factors associated with risk of work-related stairway falls." Journal of safety research 16, no. 4 (1986): 183-196.
Warren, William H. "Perceiving affordances: Visual guidance of stair climbing." Journal of experimental psychology: Human perception and performance 10, no. 5 (1984): 683.
Watzke, James R., and Bryan Kemp. "Safety for older adults: The role of technology and the home environment." Topics in Geriatric Rehabilitation 7, no. 4 (1992): 9-21.
Reader Question: how to build steps for people who have trouble climbing stairs
I am ask to build steps for an older couple, one already has a hip replacement an the other getting one done, my steps hieght is three feet an the distence is five feet they need lower risers. Can someone tell what the dimensions would be?
Reply: design the stair with a long run, deep treads, shorter rise, and secure handrailings
You can make short rise steps by making the stairway run longer.
For example if you have a total rise of five feet and you want a 3-inch step rise you'd divide (5x12=60) 60 inches by 3 inches to get 20 steps that you'd need to build to climb up five feet.
Of course you'll want to make the stair treads deeper front-to back to make such short rise steps safe and comfortable.
And secure hand railings on both sides of the stairs will be important for folks for whom stairs are difficult.
Watch out: when making stair treads "deeper" - that's increasing the distance from the stair tread nose to the stair riser - you need to avoid creating a halting-walk stairway trip and fall hazard. Simply making an 11-inch deep tread into an 18" deep tread in order to reduce the stair riser height can actually (in my OPINION) increase the risk of falling by making the foot placement difficult when descending the stairs. In that case the treads need to be deep enough to avoid a "halting walking step."
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 "The Elimination of Unsafe Guardrails, a Progress Report," Elliott O. Stephenson, Building Standards, March-April 1993
 "Are Functional Handrails Within Our Grasp" Jake Pauls, Building Standards, January-February 1991
 Access Ramp building codes:
 Access Ramp Standards:
ADA (Americans with Disabilities Act), Public Law 101-336. 7/26/90 is very often cited by other sources for good design of stairs and ramps etc. even where disabled individuals are not the design target.
ANSI A117.4 Accessible and Usable buildings and Facilities (earlier version was incorporated into the ADA)
ASTM F 1637, Standard Practice for Safe Walking Surfaces, (Similar to the above standard
 Falls and Related Injuries: Slips, Trips, Missteps, and Their Consequences, Lawyers & Judges Publishing, (June 2002), ISBN-10: 0913875430 ISBN-13: 978-0913875438 "Falls in the home and public places are the second leading cause of unintentional injury deaths in the United States, but are overlooked in most literature. This book is unique in that it is entirely devoted to falls. Of use to primary care physicians, nurses, insurance adjusters, architects, writers of building codes, attorneys, or anyone who cares for the elderly, this book will tell you how, why, and when people will likely fall, what most likely will be injured, and how such injuries come about. "
 The National Institute of Standards and Technology, NIST (nee National Bureau of Standards NBS) is a US government agency - see www.nist.gov
"A Parametric Study of Wall Moisture Contents Using a Revised Variable Indoor Relative Humidity Version of the "Moist" Transient Heat and Moisture Transfer Model [copy on file as/interiors/MOIST_Model_NIST_b95074.pdf ] - ", George Tsongas, Doug Burch, Carolyn Roos, Malcom Cunningham; this paper describes software and the prediction of wall moisture contents. - PDF Document from NIS
 Slips, Trips, Missteps and Their Consequences, Second Edition, Gary M. Bakken, H. Harvey Cohen,A. S. Hyde, Jon R. Abele, ISBN-13: 978-1-933264-01-1 or
ISBN 10: 1-933264-01-2,
available from the publisher, Lawyers ^ Judges Publishing Company,Inc., www.lawyersandjudges.com email@example.com and also from the InspectAPedia Bookstore (Amazon.com)
 The Stairway Manufacturers' Association, (877) 500-5759, provides a pictorial guide to the stair and railing portion of the International Residential Code. [copy on file as http://www.stairways.org/pdf/2006%20Stair%20IRC%20SCREEN.pdf ] -
 Mold-Resistant Building Practices, advice from an expert on how to prevent mold after a building flood and how to prevent mold growth in buildings by selection of building materials and by anti-mold construction details.
 "The Dimensions of Stairs", J. M. Fitch et al., Scientific American, October 1974.
 Stair & Walkway Standards for Slipperiness or Coefficient of Friction (COF) or Static Coefficient of Friction (SCOF)
ASTM D-21, and ASTM D2047
UL-410 (similar to ASTM D-21)
NSFI 101-B (National Floor Safety Institute)
NSFI Walkway Auditing Guideline (WAG) Ref. 101-A& 101-B (may appear as ANSI B101.0) sets rules for measuring walkway slip resist
OSHA - (Dept of Labor CFR 1910.22 does not specify COF and pertains to workplaces) but recognizes the need for a "qualified person" to evaluate walkway slipperiness
ADA (relies on the ANSI and ASTM standards)
 A. Sacher, International Symposium on Slip Resistance: The Interface of Man, Footwear, and Walking Surfaces, Journal of Testing and Evaluation (JTE), ISSN: 1945-7553, January 1997 [more focused on slipperiness of polished surfaces
 Algae is widely recognized as a slippery surface - a Google web search for "how slippery is algae on steps" produced more than 15,000 results on 8/29/12)
 Slipperiness of algae on walking surfaces, warning, Royal Horticultural Society, retrieved 8/29/2012, original source: http://apps.rhs.org.uk/advicesearch/profile.aspx?pid=418
 Slipperiness of algae: "Watch your step, wet rocks and algae are slippery" Oregon State University warning 1977 retrieved 8/29/2012, original source: http://www.worldcat.org/title/watch-your-step-wet-rocks-and-algae-are-slippery/oclc/663683915
 Coefficient of friction of algae on surfaces [like stair treads]: Delphine Gourdon, Qi Lin, Emin Oroudjev, Helen Hansma, Yuval Golan, Shoshana Arad, and Jacob Israelachvili, "Adhesion and Stable Low Friction Provided by a Subnanometer-Thick Monolayer of a Natural Polysaccharide", Langmuir, 2008 pp 1534-1540, American Chemical Society,
retrieved 8/29/2012, Abstract: Using a surface forces apparatus, we have investigated the adhesive and lubrication forces of mica surfaces separated by a molecularly thin, subnanometer film of a high-molecular-weight (2.3 MDa) anionic polysaccharide from the algae Porphyridium sp. adsorbed from aqueous solution. The adhesion and friction forces of the confined biopolymer were monitored as a function of time, shearing distance, and driving velocity under a large range of compressive loads (pressures). Although the thickness of the dilute polysaccharide was < 1 nm, the friction was low (coefficient of friction = 0.015), and no wear was ever observed even at a pressure of 110 atm over 3 decades of velocity, so long as the shearing distances were less than twice the contact diameter. Atomic force microscopy in solution shows that the biopolymer is able to adsorb to the mica surface but remains mobile and easily dragged upon shearing. The adhesion (adsorption) of this polysaccharide even to negatively charged surfaces, its stable low friction, its robustness (high-load carrying capacity and good wear protection), and the weak (logarithmic) dependence of the friction force on the sliding velocity make this class of polyelectrolytes excellent candidates for use in water-based lubricant fluids and as potential additives to synovial fluid in joints and other biolubricating fluids. The physical reasons for the remarkable tribological properties of the ultrathin polysaccharide monolayer are discussed and appear to be quite different from those of other polyelectrolytes and proteins that act as thick “polymer brush” layers.
 Jason R. Stokes, Lubica Macakova, Agnieszka Chojnicka-Paszun, Cornelis G. de Kruif, and Harmen H. J. de Jongh, "Lubrication, Adsorption, and Rheology of Aqueous Polysaccharide Solutions, Langmuir 2011 27 (7), 3474-3484
 "Coefficients of Friction for Ice", The Physics Factbook™, Glenn Elert, Ed., retrieved 8/29/12, original source: http://hypertextbook.com/facts/2004/GennaAbleman.shtml
 "Coefficients of Friction for Ice", The University of the State of New York Reference Tables for Physical Setting/Physics. New York: The State Education Department, 2002. Op. Cit.
 Serway Physics for Scientists and Engineers 4th edition (p. 126.)
 "How Slippery Is It", retrieved 8/29/12, original source http://www.icebike.org/Articles/howslippery.htm
 John E. Hunter, "Friction Values", The Source, Society of Accident Reconstructionists, Winter 1998. Study of frictional values of car tires involved in collisions on snow or ice covered roadways.
 Frictional Coefficients of some Common Materials and Materials Combinations, The Engineering Toolbox, retrieved 8/29/2012, original source: http://www.engineeringtoolbox.com/friction-coefficients-d_778.html [copy on file as Friction and Coefficients of Friction.pdf ]
 Stairways and Ladders, A Guide to OSHA Rules, OSHA, U.S. Department of Labor, 3124-12R 2003 - Web Search 05/28/2010 original source: http://www.osha.gov/Publications/osha3124.pdf. OSHA regulations govern standards in the construction industry and in the workforce Quoting from OSHA whose focus is on workplace safety and so excludes discussion of falls and stair-falls in private homes:
OSHA estimates that there are 24,882 injuries and as many as 36 fatalities per year due to falls from stairways and ladders used in construction. Nearly half of these injuries are serious enough to require time off the job--11,570 lost workday injuries and 13,312 non-lost workday injuries occur annually due to falls from stairways and ladders used in construction. These data demonstrate that work on and around ladders and stairways is hazardous. More importantly, they show that compliance with OSHA's requirements for the safe use of ladders and stairways could have prevented many of these injuries. -osha.gov/doc/outreachtraining/htmlfiles/stairlad.html
 International Building Code, Stairway Provisions, Section 1009: Stairways and Handrails, retrieved 8/29/12, original source: http://www.amezz.com/ibc-stairs-code.htm [copy on file as IBC Stairs Code.pdf]
 Model Building Code, Chapter 10, Means of Egress, retrieved 8/29/12, original source: http://www2.iccsafe.org/states/newjersey/NJ_Building/PDFs/NJ_Bldg_Chapter10.pdf, [copy on file as NJ_Bldg_Chapter10.pdf] adopted, for example by New Jersey. International Code Council, 500 New Jersey Avenue, NW, 6th Floor, Washington, DC 20001, Tel: 800-786-4452
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