Provides citations of stair and railing code & design specifications quoted from model building codes. For each stair specification & code citation we include links to in-depth articles providing more details.
This article series lists all major building code specifications for stairs, railings, landings, and guardrails - information useful for constructing or inspecting indoor or outdoor stairs, railings, landings, & treads, and for evaluating stairways and railings for safety and proper
construction. We compare stair and railing code requirements for various model, national, state and local building codes and we include explicit text & specifications from those building codes.
all interior stairs and railings shall be maintained in sound condition and good repair.
Commentary: Handrails, treads and risers must be structurally sound, firmly attached to the structure, and properly maintained to perform their intended function safely. During an inspection the code official should inspect all stringers, risers, treads, and handrails.
PM-305.6 Handrails and guards
Every handrail and guard shall be firmly fastened and capable of supporting normally imposed loads and shall be maintained in good condition.
Commentary: This section provides for the safety and maintenance of handrails and guards. See Section PM-702.9 for additional requirements.
PM-702.9 Stairways, handrails and guards
Every exterior and interior flight of stairs having more than four risers, and every open portion of a stair, landing or balcony which is more than 30 inches (762mm) high, nor more than 42 inches (1067mm) high, measured vertically above the nosing of the tread or above the finished floor of the landing or walking surfaces. Guards shall be not less than 30 inches (762mm) high above the floor of the landing or balcony.
Commentary: Handrails are required on all stairs more than four risers in height. Handrails cannot be less than 30 inches nor more than 42 inches above the nosing of the treads (see Figure PM-702.9).
Guards are required on the open side of stairs and on landings and balconies which are more than 30 inches above the floor or grade below. The guard must be at least 30 inches above the floor of the landing or balcony.
Guards are to contain intermediate rails, balusters or other construction to reduce the chance of an adult or child from falling through the guard. If the guard is missing some intermediate rails or balustrades, it is recommended that the guard be repaired to its original condition if it will provide protection equivalent to the protection it provided when originally constructed.
International Building Code 2000 (BOCA, ICBO, SBCCI) Stair & Railing Codes
1003.3.3.4 Stairway Landing Codes
There shall be a floor or landing at the top and bottom of each stairway. The width of landings shall not be less than the width of stairways they serve. Every landing shall have a minimum dimension measured in the direction of travel equal to the width of the stairway. Such dimension need not exceed 48 inches (1219 mm) where the stairway has a straight run.
Our photo (left) illustrates the author (DF) holding on to a secure, graspable handrail in a building in Bar Harbor, Maine. Also see
"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
Handrails with a circular cross section shall have an outside diameter of at least 1.25 inches (32 mm) and not greater than 2 inches (51 mm) or shall provide equivalent grasp ability.
If the handrail is not circular, it shall have a perimeter dimension of at least 4 inches (102 mm) and not greater than 6.25 inches (159 mm) with a maximum cross-section dimension of 2.25 inches (57 mm). Edges shall have a minimum radius of 0.125 inch (3.2 mm).
100333.11.4 Handrail or Guardrail Continuity
Handrail-gripping surfaces shall be continuous, without interruption by newel posts or other obstructions.
1607.7 Loads on Handrails, guards, grab bars and vehicle barriers
1607.7.1.1 Concentrated Load on Railings
Handrail assemblies and guards shall be able to resist a single concentrated load of 200 pounds (0.89kN), applied in any direction at any point along the top, and have attachment devices and supporting structure to transfer this loading to appropriate structural elements of the building.
1607.7.1.2 Component of Railings and Guardrails
Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds (0.22 kN) on an area not to exceed one square foot (305mm2) including openings and space between rails.
Full Text of IEBC International Existing Building Code & Definitions of Dangerous Building Conditions
2008 New York State Residential Building Code Stair Design Specifications
This building code update for stairway design specifications was provided courtesy Arlene Puentes.
R318.104.22.168 Stair Riser Height Codes
The maximum riser height shall be 8 1 / 4 inches (209 mm). The riser shall be measured vertically between leading edges of the adjacent treads. The greatest riser height within any flight of stairs shall not exceed the smallest by more than 3 / 8 inch (9.5 mm).
R322.214.171.124 Stair Tread Depth Code Requirements
The minimum tread depth shall be 9 inches (229 mm). The tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread's leading edge.
The greatest tread depth within any flight of stairs shall not exceed the smallest by more than 3 / 8 inch (9.5 mm). Winder treads shall have a minimum tread depth of 10 inches (254 mm) measured as above at a point 12 inches (305) mm from the side where the treads are narrower.
Winder treads shall have a minimum tread depth of 6 inches (152 mm) at any point. Within any flight of stairs, the greatest winder tread depth at the 12 inch (305 mm) walk line shall not exceed the smallest by more than 3 / 8 inch (9.5 mm).
R3126.96.36.199 Stair Tread Nose Profile Code Requirements
The radius of curvature at the leading edge of the tread shall be no greater than 9 / 16 inch (14.3 mm). A nosing not less than 3 / 4 inch (19 mm) but not more than 1 1 / 4 inch (32 mm) shall be provided on stairways with solid risers.
The greatest nosing projection shall not exceed the smallest nosing projection by more than 3 / 8 inch (9.5 mm) between two stories, including the nosing at the level of floors and landings.
Beveling of nosing shall not exceed 1 / 2 inch (12.7 mm). Risers shall be vertical or sloped from the underside of the leading edge of the tread above at an angle not more than 30 (0.51 rad) degrees from the vertical. Open risers are permitted, provided that the opening between treads does not permit the passage of a 4-inch diameter (102 mm) sphere.
Exceptions to Stair Tread Nose Requirements:
1. A nosing is not required where the tread depth is a minimum of 11 inches (279 mm).
2. The opening between adjacent treads is not limited on stairs with a total rise of 30 inches (762 mm) or less
Stair Tread Anti-Slip or Coefficient of Friction Recommendations for Safe Walking Surfaces
[Not found in NYS Code]
A walking-surface that provides a coefficient of friction of 1.02 dry and 0.98 wet will comply with ADA, OSHA, and most local building codes and insurance requirements. Other sources (cited in the two articles listed just below) cite a coefficient of friction of 0.5 (OSHA) or 0.6 (ADA) as the minimum recommended COF to avoid slippery walking surfaces and stairways.
Also see EXTERIOR STAIR FALLS for a catalog of causes of falls on stairs that includes surface conditions and other defects.
R3188.8.131.52 Spiral Stairway & Circular Stairway Building Codes
Above; minimum tread dimensions for a spiral stairway, adapted from the 2006 IRC as published by Juneau AK IRC R311.5. [Click to enlarge any image]
Spiral stairways are permitted for interior use as a component of the means of egress from a habitable room, a basement or an attic, provided the minimum width shall be 26 inches (660 mm) with each tread having a 7 1 / 2 -inch (190 mm) minimum tread depth at 12 inches from the narrower edge.
All treads shall be identical, and the rise shall be no more than 9 1 / 2 inches (241 mm).
A minimum headroom of 6 feet 6 inches (1982 mm) shall be provided. A spiral stair is not permitted to be the only means of egress from a story of a building.
Many codes require use of a guard or rail to prevent walking too close to the inside of a circular stair where the tread dimensions are too small for safe use.
The minimum tread depth shall be 10 inches (254 mm). The tread depth shall be measured
horizontally between the vertical planes of the foremost projection of adjacent treads and at a right angle to the tread’s
The greatest tread depth within any flight of stairs shall not exceed the smallest by more than 3/8 inch (9.5
mm). Winder treads shall have a minimum tread depth of 10 inches (254 mm) measured as above at a point 12
inches (305) mm from the side where the treads are narrower.
Winder treads shall have a minimum tread depth of 6
inches (152 mm) at any point. Within any flight of stairs, the greatest winder tread depth at the 12 inch (305 mm) walk line
shall not exceed the smallest by more than 3/8 inch (9.5 mm).
R3184.108.40.206 Spiral stairways.
Spiral stairways are permitted, provided the minimum width shall be 26 inches (660 mm) with
each tread having a 71/2-inches (190 mm) minimum tread depth at 12 inches from the narrower edge.
All treads shall be
identical, and the rise shall be no more than 91/2 inches (241 mm). A minimum headroom of 6 feet 6 inches (1982 mm) shall
WAC 296-155-477 (3)(b) Winding and spiral stairways must be equipped with a handrail offset sufficiently to prevent walking on
those portions of the stairways where the tread width is less than 6 inches (15 cm).
Above; minimum tread dimensions for a Winder stairway, adapted from the 2006 IRC as published by Juneau AK IRC R311.5. [Click to enlarge any image]
The following general requirements apply to all stairways used during the process of construction, as indicated:
Stairways that will not be a permanent part of the structure on which construction work is performed must have landings at least 30 inches deep and 22 inches wide (76 x 56 cm) at every 12 feet (3.7 m) or less of vertical rise.
Stairways must be installed at least 30 degrees, and no more than 50 degrees, from the horizontal.
Variations in riser height or stair tread depth must not exceed 1/4 inch in any stairway system, including any foundation structure used as one or more treads of the stairs.
Where doors or gates open directly onto a stairway, a platform must be provided that is at least 20 inches (51 cm) in width beyond the swing of the door.
Metal pan landings and metal pan treads must be secured in place before filling.
All stairway parts must be free of dangerous projections such as protruding nails.
Slippery conditions on stairways must be corrected.
Spiral stairways that will not be a permanent part of the structure may not be used by workers.
The following requirements apply to stairs in temporary service during construction:
Except during construction of the actual stairway, stairways with metal pan landings and treads must not be used where the treads and/or landings have not been filled in with concrete or other material, unless the pans of the stairs and/or landings are temporarily filled in with wood or other material. All treads and landings must be replaced when worn below the top edge of the pan.
Except during construction of the actual stairway, skeleton metal frame structures and steps must not be used (where treads and/or landings are to be installed at a later date) unless the stairs are fitted with secured temporary treads and landings.
Temporary treads must be made of wood or other solid material and installed the full width and depth of the stair.
OSHA Regulations for Stair Railings & Guardrails
STAIRRAILS AND HANDRAILS
The following general requirements apply to all stair rails and handrails:
Stairways having four or more risers, or rising more than 30 inches (76 cm) in height, whichever is less, must have at least one handrail. A stairrail also must be installed along each unprotected side or edge. When the top edge of a stairrail system also serves as a handrail, the height of the top edge must not be more than 37 inches (94 cm) nor less than 36 inches (91.5 cm) from the upper surface of the stairrail to the surface of the tread.
Winding or spiral stairways must be equipped with a handrail to prevent using areas where the tread width is less than 6 inches (15 cm).
Stairrail's installed after March 15, 1991, must not be less than 36 inches (91.5 cm) in height.
Mid rails, screens, mesh, intermediate vertical members, or equivalent intermediate structural members must be provided between the top rail and stairway steps of the stairrail system.
Mid rails, when used, must be located midway between the top of the stairrail system and the stairway steps.
Screens or mesh, when used, must extend from the top rail to the stairway step, and along the opening between top rail supports.
Intermediate vertical members, such as balusters, when used, must not be more than 19 inches (48 cm) apart.
Watch out: these are OSHA requirements and address construction and work environments, not residential requirements. Other stair code requirements reduce this number substantially, e.g. to 4" with added details to avoid a head trap and other child hazards. - Ed.]
Other intermediate structural members, when used, must be installed so that there are no openings of more than 19 inches (48 cm) wide.
Handrails and the top rails of the stairrail systems must be capable of withstanding, without failure, at least 200 pounds (890 n) of weight applied within 2 inches (5 cm) of the top edge in any downward or outward direction, at any point along the top edge.
The height of handrails must not be more than 37 inches (94 cm) nor less than 30 inches (76 cm) from the upper surface of the handrail to the surface of the tread.
The height of the top edge of a stairrail system used as a handrail must not be more than 37 inches (94 cm) nor less than 36 inches (91.5 cm) (1) from the upper surface of the stairrail system to the surface of the tread.
Stairrail systems and handrails must be surfaced to prevent injuries such as punctures or lacerations and to keep clothing from snagging.
The ends of stairrail systems and handrails must be constructed to prevent dangerous projections such as rails protruding beyond the end posts of the system.
See SNAG HAZARDS on STAIRWAYS
Temporary handrails must have a minimum clearance of 3 inches (8 cm) between the handrail and walls, stairrails systems, and other objects.
Unprotected sides and edges of stairway landings must be provided with standard 42-inch (1.1 m) guardrail systems.
Canadian Occupational Safety Regulations - Stairways & Fall Prevention
Why do we need to worry so much about falls on stairs?
Stairs of all types have been used since ancient times, and because they are inherently hazardous, people have been falling on them, getting hurt or even killed in the process. In North America tens of people die and tens of thousand people get injured every year from the falls on stairs. The American National Council on Compensation Insurance estimated in 2001-2002 that the cost of such fall injuries was second only to those caused by motor vehicles.
The vast majority of stairway falls result from a loss of balance, just as falls are on the level.
A very common contributing factor is neglecting to use handrails. The consequences can be quite nasty.
Because stairway accidents can cause severe injury and even death, building codes for stairs and ramps are justifiably very rigorous. Good design can substantially reduce the potential for mis-stepping by providing us with the means to retrieve our balance, but even the best design cannot eliminate falling hazards entirely. The need for proper design also applies to ramps. The fact is that some incidents can be caused by inattention and unsafe behaviour.
The best approach to minimize the hazard of falling down stairs is to encourage the building of well-designed stairways, combined with training focused on raising our awareness of the potential for disaster.
Details about inspecting for stair hazards likely to cause a slip, trip, or fall injury are at
What factors must we consider in designing safer stairs?
Stair dimensions - Canadian Rules
Figure 1 shows the recommended dimension ranges for all the important elements of stairways.
Figure 1: Legend
A - Optimal range: 30º-35º
B* - Handrail height: 80-96.5 cm
C* - Riser height: 12.5-20 cm
D* - Step width: 90 cm min.
E* - Tread depth: 23.5-35.5 cm
* Values are from the National Building Code of Canada (2005). Always check with your local jurisdiction as requirements are different in each area.
The maximum range for a stair slope is 20º-50º. However, because the majority of people prefer a slope of 30º-35º, this is the recommended range.
Steeper stairs change the way you climb them because the steeper they are the more effort you exert. The ratio of riser height and tread depth has to be adjusted accordingly. (See Figures 2 and 3)
From: Kodak's ergonomic design for people at work. 2nd ed. John Wiley & Sons, 2004. p.244
The dimension of risers or treads in a stairway should not vary more than 1 cm. When doors open directly into the stairwell, a 50 cm-wide platform should be provided beyond the swing of the door. The recommended maximum number of steps between landings is 18, with no more than two flights without a change of direction. The depth of any landing should be at least equal to the width of the stairs.
Stair surface - Canadian Rules
To reduce the risk of slipping on stairs, non-slippery surface on the whole steps or at least on the leading edges is crucial. Such a surface can be made of rubber, or metal or painted with special slip-resistant paint. Regular maintenance of the stairs in good repair plus good housekeeping can reduce hazards for tripping.
Stair handrails - Canadian Requirements
Attempts to design aesthetically pleasing stairways including handrails must not compromise functionality.
The prime function of the handrail is for holding as support while going up or down stairs.
It is therefore crucial to be able to grasp it quickly, easily and firmly if you should start losing your balance.
Figure 4 (left) shows the recommended cross-section and dimensions of a good handrail. Ideally the cross-section should be round (diameter 4-5 cm, with circumference of 12-14 cm) to allow for a good firm grip.
You should be able to run your hand smoothly along the entire length without having to adjust your grip. You should apply the so-called "tennis-racket grip" at all times when possible.
Guardrails of at least 40 cm above the surface of the stairs are needed to prevent falls off the side of the stairs that are not equipped with a banister.
Visibility on stairs
Improving visibility on stairs significantly reduces the risk for common mishaps caused by misjudging distances. Otherwise you can trip on a step or miss it completely. You can catch a heel on the edge of a step. Such mishaps are a routine cause of twisted ankles, sprained knees or more serious injuries incurred by a total fall.
Recommended illumination should be at the minimum 50 lux level. Use angular lighting and colour contrast to improve depth perception. Use matte finishes on the treads to avoid glare. Avoid patterned carpeting that may visually hide differences in depth.
Be very cautious on stairs if you are wearing bifocal glasses.
Work activity on stairs
Use any means to persuade people to grasp the handrail while both ascending or descending stairs. Avoid carrying objects with both hands.
Do not carry bulky objects that block your vision.
Housekeeping Requirements for Stairways
Good housekeeping is also vital to stair safety:
Nothing should be sticking out the surfaces of stairs, handrails or bannisters (like nails or splinters) that could cause a fall. Spills, wet spots, or any debris should be immediately cleaned up.
Broken or malfunctioning lighting should be repaired or replaced.
Continue reading at STAIR DIMENSIONS, WIDTH, HEIGHT or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.
Try the search box below or CONTACT US by email if you cannot find the answer you need at InspectApedia.
is an exception to step riser height uniformity allowed when using pre-fab stair stringters?
Is there an exception to the riser height variation for the very first step of the staircase? Let me attempt to clarify the question. I have a deck (exterior porch) for which the distance from the top of the deck to the slab which forms the footing for the set of stairs is just shy of the 5 steps within a pre-fabricated 5 step stair stringer which can be purchased at a Home Depot or Lowes, for example.
If I attach the pre-made stringer from the deck to the slab, ensuring that the top of the deck to the next stair down is the same height as the rest, then the riser height from the slab to the first stair is greater than a 3/8" variation from the rest of the riser heights by 1/8th of an inch (ie. it's 1/2 inch shorter than the rest of the stairs - I actually need to remove a half inch from the bottom most stair of the stringer to fit). If this is a violation of code, than it means I need to cut my own customer stringer. Just verifying. Any feedback is appreciated. - Dan
Reply: In short, no, but in this case you can adjust the stringer to meet code
Dan we answered this question previously in detail at STAIR RISER SPECIFICATIONS - please take a look at that article. In short, because your step riser height variation at the first step is 1/2" shorter than the rest of the stairs, you can trim the top and bottom of the stair stringer to split that difference, making sure that the variation in step riser height is 1/4" or less - which meets code.
Is there a minimum weight capacity for wooden stairs? - Hendrick
Hendrick: regarding stair load capacity, the best answer is to start by asking your local building department - the local code officials are the final authority on stair load capacity requirements.
Based on the 1997 Uniform Building Code (TM), the 2000 International Building Code (R), and the 2000 International Residential code (R) IRC, and looking at a popular stair construction bracket (the EZ-stair bracket), the allowable download on the bracket is 610-640 pounds (including snow loads on exterior stairs). Typical deck & post load numbers range from 650 to 1050 lbs/sqft.
Naturally all of the stair structural and other weight bearing components have to be constructed to handle the live and dead loads involved. And you can increase the load bearing capacity or weight carrying capacity of your stairs by increasing the size of the stair stringers.
Watch out: we have seen amateur-built stairs at which the stair stringers were cut so deeply to prepare notches for the treads and risers that the entire stairway was being supported by what amounted to a 2x3!!
Question: do I need to remodel stairs in a 1979 rental cabin to comply with current building codes
I purchased a cabin recently, the cabin was built in 1979, at that time the building code for stairs was different than the code today. I do rent the cabin. Do I need to remodeled the stair to be conform to the new building codes? - Mike Jones
Reply: requirement to update stairs to meet current building codes: no, sometimes yes, but ...
Mike, re: requirement to update stairs to meet current building codes:
While the final answer to your question is in the hands of your local building department, usually building owners are not required to change or update their building to keep up with building code updates.
But often a building owner can indeed find themselves obligated to update certain portions of the building or its mechanical systems to current building codes
when the property is being sold (as part of a "CO" update that may be required by the buyer or their mortgage lender),
when an addition or modification to the building is being constructed, for which building permits and code approvals are required.
In my OPINION, because stair falls are the greatest source of injuries and hospitalizations in North America after automobile accidents, it is worth making stairs, railings, landings, and guardrails as safe as possible. You didn't mention anything specific about your cabin stairs, but certainly as a landlord, renting the property, you have an extra level of responsibility to your tenants to make the building safe, and you certainly don't want someone to be injured. I'd be sure to pay attention to basic trip and fall hazards such as uneven risers or treads, and inadequate railings.
Question: code on smoothness of stair landing surfaces
(Apr 15, 2014) Peter said:
Is there a code requirement or a reference standard (specifically in California )requiring that the surface of a landing be smooth to within a certain tolerance?
Peter I haven't seen smoothess per se, but there are certainly building codes about trip hazards and about uniformity of surface in slope or pitch;
But you can express a trip hazard in terms of
Uneven heights or projections in the walking surfaces: Generally something sticking up more than 1/8" or a gap wider than 1/8" can be a trip hazard.
See SLIPS, TRIPS & FALLS, EXTERIOR STAIRS
Surfaces that are too slippery - lacking an adequate static coefficient of friction
See SLIPPERY STAIRS, WALKS
Question: requirements for transitioning from top landing to stair tread
(Apr 24, 2014) email@example.com said:
I am unable to find where the requirements for transitioning from top landing to stair tread is. The deck i have bas the top stair about a 1/2 inch above the landing i think it is a trip hasard but i cant find any presedence that confirms that. or code? any help would be appreciated. Thanks, Richard Townes. Alabama if that make a differance
Hi Richard. I think I need to see a sketch or photo - I'm confused by the text.
Certainly a 1/2" Rise or irregularity in a flat walking surface is a trip hazard. But a 1/2" rise created by say a door-threshold would be normal.
If you mean that the last stair tread in stairs that climb up to the surface of a deck is actually 1/2" above the deck surface that's certainly a trip hazard. I'd expect your building department to agree. And I'd look out for an inexperienced stair installer / builder and worry about what other oddball stuff is there.
Question: Florida stair codes for stair replacement
(Aug 8, 2014) SANDRA FISHER said:
I live in a 8 unit condo building in Florida. Our back exterior stair case needs to be replaced. Are there any codes and specifications that you can direct me too please?
Sandra, the Florida Building Code Section 1009 describes the state's requirements for stairs and handrailings. I'll post a link to a copy of the Florida State Stair & Railing Code in the article above -
In links at the start of this article click on
FLORIDA STAIR & RAILING CODE [PDF]
click in that document to return to this page.
Question: inconsistent step rise on stairs vs at landings
(Nov 28, 2014) Anonymous said:
My house is about 15 years old will good prefab stairs between the basement and first floor and the first and second floors. In both cases each rise is exactly 7.75 inches. However, in both cases the top stair to landing is not 7.75. In one case, it is 8.25 inches(top stair from basement to first floor)and in the other case it is 6.5 inches (top stair from first to second floor). Is this legal?
The variations in step riser height you cite are a potential trip hazard and are not in compliance with most stair codes. What's "legal" is what was approved by your local building inspector.
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Eric Galow, Galow Homes, Lagrangeville, NY. Mr. Galow can be reached by email: firstname.lastname@example.org or by telephone: 914-474-6613. Mr. Galow specializes in residential construction including both new homes and repairs, renovations, and additions.
 "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 NI
 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 ] -
[14a] "Visual Interpretation Of The International Residential Code (IRC) 2006 Stair Building Code", The Stairway Manufacturers Association, [Portions of this document reproduce sections from the 2006 International Residential Code, International Code Council, Falls Church, Virginia.},
The Stairway Manufacturers Association website stairways.org provides free downloads of stairway handrailing profiles and dimensions
 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
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
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