Stepladders: Why They’re Not Safe

2008 ◽  
Author(s):  
K. J. Seluga ◽  
L. L. Baker ◽  
I. U. Ojalvo
Keyword(s):  
Failure Modes ◽  
National Standards ◽  
Specific Design ◽  
Design Standards ◽  
Consumer Product Safety Commission ◽  
Safety Standards ◽  
Potential Safety ◽  
The Us ◽  
Design And Manufacturing ◽  
Current Design

The US Consumer Product Safety Commission (CPSC) estimates that there are approximately 180,000 serious ladder accidents in the US each year. Stepladders are one of the most common types of ladders in use, and it is estimated that they are involved in over half of all incidents. Therefore, it is important to determine the root causes of these accidents and what, if anything, can be done to improve ladder safety by way of design and standard testing requirements. Herein, we discuss common failure modes experienced during use, current design standards promulgated by the American National Standards Institute (ANSI) A14 Standards Committee, complications which are not explicitly addressed in these standards, and design and manufacturing practices employed in stepladders produced for the US market. Finally, we propose a number of potential safety improvements to the current design of and safety standards for stepladders, though further research may be necessary to quantify specific design recommendations.

Cold-formed steel battened built-up columns: Experimental behaviour and verification of different design rules developed

2021 ◽  
pp. 136943322110480
Author(s):  
A.R. Dar ◽  
S. Vijayanand ◽  
M. Anbarasu ◽  
M. Adil Dar
Keyword(s):  
Failure Modes ◽  
Numerical Models ◽  
Experimental Studies ◽  
Design Standards ◽  
Uniform Compression ◽  
Design Rules ◽  
The North ◽  
Current Design ◽  
Cold Formed Steel ◽  
In The Beginning

Some of the past studies on cold-formed steel (CFS) battened built-up columns have resulted in the development of new design rules for predicting their axial strengths. However, the main drawbacks of such studies are that they are purely numerical and the numerical models developed for such parametric studies were validated using the test results on similar built-up column configurations, but not the exact ones. Therefore, experimental studies on CFS battened columns comprising of lipped channels are needed for verifying the accuracy of the proposed design rules for CFS battened columns. This paper reports an experimental study performed on CFS built-up battened columns under axial compression. Adequately spaced identical lipped channels in the back-to-back arrangement were used as chords and were connected by batten plates laterally with self-driving screws to form the built-up members. The dimensions of chords were fixed as per the geometric limits given out in the North American Specifications (NAS) for the design of CFS structural members. The sectional compactness of the chords and the overall slenderness of the built-up columns were varied by altering the thickness of the channels and height of the built-up columns, respectively. A total of 20 built-up sections were tested under uniform compression to investigate the behavioural changes in the built-up columns due to these variations. The behaviour assessment was made in terms of peak strengths, load–displacement response and failure modes of the test specimens. The current design standards on CFS structures were used to determine the design strengths and were compared against the test strengths for assessing their adequacy. Furthermore, as discussed in the beginning, the test strengths were used to verify the accuracy of the different relevant proposed design rules in the literature.

Activation of emergency management at the Islamic university Gaza with proposed scenarios to reduce risks and crises | تفعيل إدارة الطوارئ بالجامعة الإسلامية بغزة: مع سيناريوهات مقترحة للحد من المخاطر والأزمات

2020 ◽  
pp. 145-166
Keyword(s):  
Emergency Management ◽  
Fire Risk ◽  
National Standards ◽  
Safety Standards ◽  
Human Element ◽  
Laboratory Facilities ◽  
Specialized Team ◽  
The University ◽  
Work Done ◽  
Safety Procedures

Emergency management is one of the priorities of the contemporary universities, because of the risks faced by the university work of academic and technical fields. This risk may be the result of the nature of the work done by the human element or of natural disasters or through the risks integrated between them. The study aimed to determine the availability of security and safety procedures in the Islamic University facilities in the Gaza, Palestine. Also, to prepare proposed scenarios for emergency management based on risk assumptions. The study used the descriptive and analytical methodologies of the situation in laboratory facilities and engineering workshops by using the interview tool with the emergency specialists in the safety and security committee. The most important results of the study were that the security and safety standards of the Islamic University are not directly defined by international, regional or national standards, but the necessary requirements are deducted from the University. Also, the risks that threaten the University include: fire risk, the risk of explosions, the risk of bombing, mechanical hazards and human hazards, where the risk of fire is most likely. The study recommended the need to form an emergency committee to include all faculties in the University and work to determine the responsibilities accurately, also prepare a guide to educate students and staff of the threats of risks at the Islamic University, and the formation of a specialized team to evacuate facilities and evacuate the special needs in the event of an emergency. Keywords: The Islamic University-Gaza, Emergency, Risk, Security and Safety, Emergency Response. --------------------------------------------- تعد إدارة الطوارئ من الأولويات لدى الجامعات المعاصرة؛ وذلك لما يتعرض له العمل الجامعي من مخاطر في المجالات الأكاديمية والفنية، وهذا الخطر قد يكون ناتجاً عن طبيعة العمل الذي يقوم به العنصر البشري أو من الكوارث الطبيعية أو من خلال المخاطر المدمجة بينها. هدفت الدراسة إلى تحديد مدى توافر إجراءات الأمن والسلامة في مرافق الجامعة الإسلامية بغزة، فلسطين، مع إعداد سيناريوهات مقترحة لإدارة الطوارئ في الجامعة الإسلامية بناءً على فرضيات الخطر. وتم استخدام المنهج الوصفي والمنهج التحليلي للوضع القائم في المرافق المخبرية والمشاغل الهندسية, وذلك من خلال استخدام أداة المقابلة مع المختصين في مجال الطوارئ في لجنة الأمن و السلامة. كانت أهم نتائج الدراسة أن معايير الأمن والسلامة المتبعة في الجامعة الإسلامية غير محددة بشكل مباشر من المعايير الدولية أو الإقليمية أو الوطنية، ولكن يتم استقطاع ما يلزم الجامعة منها، كذلك المخاطر التي تهدد الجامعة الإسلامية تشمل خطر الحريق، وخطر الانفجارات، وخطر القصف، والأخطار الميكانيكية, والمخاطر البشرية بحيث تعتبر مخاطر الحريق الأكثر احتمالاً. وقد أوصت الدراسة بضرورة تشكيل لجنة طوارئ تشمل كل الكليات في الجامعة, وتحديد المسئوليات بها بدقة، وإعداد دليل إرشادي معلن للتوعية الطلبة والعاملين من المخاطر التي تهدد الجامعة، وتشكيل فريق متخصص لإخلاء المرافق وإخلاء ذوي الاحتياجات الخاصة في حالة حدوث طارئ. الكلمات المفتاحية: الجامعة الإسلامية بغزة، إدارة الطوارئ، المخاطر، الأمن والسلامة، الاستجابة للطوارئ.

Safety at Curves and Road Geometry Standards in Some European Countries

1996 ◽  
Vol 1523 (1) ◽  
pp. 99-106 ◽  
Author(s):  
Thierry Brenac
Keyword(s):  
Urban Areas ◽  
National Standards ◽  
European Countries ◽  
Design Standards ◽  
The Road ◽  
Horizontal Curves ◽  
Road Design ◽  
Road Geometry ◽  
Design Speed ◽  
Curve Geometry

This paper deals with safety at horizontal curves on two-lane roads outside urban areas and the way the road design standards of different European countries account for this safety aspect. After a review of some research results, the main aspects of curve geometry and the curve's place in the horizontal alignment are analyzed. The main conclusions are that the traditional design speed approach is insufficient and that formal complementary rules in road design standards, especially to improve compatibility between successive elements of the alignment, must be introduced. If such complementary rules already exist in some national standards, they are neither frequent nor homogeneous throughout the different countries, and it seems that they are not based on sufficiently developed knowledge.

scholarly journals Machine Safety: Risk Assessment, Risk Reduction

2006 ◽  
Author(s):  
Michael D. Ladd
Keyword(s):  
Risk Assessment ◽  
Risk Reduction ◽  
Equipment Design ◽  
Worker Safety ◽  
End User ◽  
Safety Risk ◽  
Safety Standards ◽  
The Us ◽  
Machine Safety

Worker safety is an issue of major concern worldwide. Evidence to this fact is noted with recent efforts to harmonize US machine safety standards with that of the European Machinery Directive. Changes to the US standards have a dramatic affect on new equipment design. Additionally, older machinery that is still in use must now be upgraded to meet these new requirements. In other words, the end user must now follow the same standards as new equipment manufacturers. Paper published with permission.

scholarly journals Calculation features of wall panels with monolithic cement bond of layers in the stages of installation, transportation and maintenance

Vestnik MGSU ◽  
2019 ◽  
pp. 367-375 ◽  
Author(s):  
Elena A. Korol’ ◽  
Marina N. Berlinova
Keyword(s):  
Middle Layer ◽  
Structural Features ◽  
Design Parameters ◽  
Competitive Advantages ◽  
Design Standards ◽  
Wall Panels ◽  
Multilayer Wall ◽  
Current Design ◽  
Infinite Variety ◽  
Construction Practice

Introduction. When building residential, public and administrative buildings of various spatial structural designs (monolithic, precast-monolithic, precast, etc.), it is common practice to design self-sustaining (non-structural) outer walls within a storey. Developing and using new design and fabrication solutions of multilayer industrial-made wall panels in modern construction practice makes actual the issue of improving methods of their calculation in different stages of maintenance and under various sorts and combinations of loads and effects. However, there is an infinite variety of possible loading levels in practice and, therefore, the same variety of design approaches would be required. This is obviously unacceptable for engineering calculations, hence it is necessary to provide a monolithic matrix bond of layers, both technologically and structurally, which can provide a generalized approach to the calculation of multilayer enclosing structures in accordance with current design standards. Materials and methods. The article describes structural features of a multilayer wall panel made of structural concrete with the middle layer of concrete with low thermal conductivity and monolithic bond of layers. These features have an influence on creation of a design model and a calculation procedure in the stages of transportation, installation and maintenance. Results. The article has examined the structures described above in the sense of design parameters that provide their competitive advantages in strength and maintenance as compared with conventional mass-built enclosures. Conclusions. The studies demonstrate that when combining loads of force and non-force character, stresses in the considered structure do not exceed allowable values in all the stages what proves the prospects of using the multilayer panels with monolithic bond of layers for erection of various-purpose frame-panel buildings.

All-Terrain Vehicles: Two-, Three-, and Four-Wheeled Unlicensed Motorized Vehicles

PEDIATRICS ◽  
1987 ◽  
Vol 79 (2) ◽  
pp. 306-308 ◽  
Author(s):  
Keyword(s):  
Motor Vehicle ◽  
Product Safety ◽  
Consumer Product ◽  
Motor Vehicles ◽  
Emergency Rooms ◽  
Consumer Product Safety Commission ◽  
Safety Standards ◽  
Consumer Product Safety ◽  
Design Characteristics ◽  
The 1960S

TWO-WHEELED VEHICLES Miniature motorcycles intended for off-road use by children and adolescents have enjoyed wide popularity since the 1960s.1 Manufacture of these small two-wheeled motor vehicles is not regulated by any federal motor vehicle safety standards. Neither the rider nor the vehicle are required to be licensed. Some of these vehicles are small enough for a 4-year-old child and many are intended for use by school-aged children.2 Minibikes, weighing less than 45 kg (100 lb), are the smallest and most primitive of these vehicles. The more sophisticated minicycles are constructed to resemble miniature motorcycles. Trailcycles are larger than minicycles and have power and design characteristics that make them suitable for rough terrain. All of these vehicles have a short wheelbase and a low profile; thus, they are relatively unstable and poorly visible.3 Injuries In 1978, there were approximately 19,000 motorbike-related injuries treated in emergency rooms. Nearly half of these injuries were attributed to accidents involving the minibike (US Consumer Product Safety Commission, news release, Aug 27, 1979). In 1982, there were an estimated 12,000 children 14 years of age and younger who suffered minibike- and trailbike-related injuries (National Electronic Injury Surveillance data, National Information Clearing House, US Consumer Product Safety Commission, 1985). Since 1980, the Consumer Product Safety Commission has collected at least 24 death certificates that implicate minibikes and trailcycles. Half of those who died were children 14 years of age or younger. Children often use these vehicles illegally on roadways. Injury typically results from falls or collisions with fixed objects or other motor vehicles.

A review of techniques and errors involved in sound isolation testing

2021 ◽  
Vol 263 (3) ◽  
pp. 3176-3186
Author(s):  
Jameson Dickman
Keyword(s):  
Best Practices ◽  
Construction Industry ◽  
Background Noise ◽  
Green Building ◽  
Design Standards ◽  
Field Verification ◽  
The Us ◽  
New Construction ◽  
Standards And Guidelines ◽  
Review Current

Construction industry design standards are increasingly calling for new construction to be inspected and tested for compliance with design specifications after the project is built; otherwise known as the commissioning process. As part of this trend, owners, sensitive to the acoustics of their facilities, are seeking confirmation via measurements that their buildings meet sound isolation and background noise requirements, particularly when pursuing certifications under the US Green Building Council LEED standard, the WELL Building Standard, or other green building or wellness standards. In general, the error of sound isolation measurements is not officially established. This poses challenges to designers tasked with specifying assemblies and components to meet field verification requirements. This paper will briefly review current research and standards on the error of measurements such as Noise Isolation Class (NIC) and the Weighted Level Difference (D) and discuss example design standards and guidelines which do or do not account for this error. It will also propose further research topics to better define the error in sound isolation measurements and best practices when establishing or designing to sound isolation criteria in new or renovated buildings.

scholarly journals Introduction

2020 ◽  
Vol 48 (2) ◽  
pp. 391-405
Author(s):  
Nathan K. Hensley
Keyword(s):  
United States ◽  
Homeland Security ◽  
The United States ◽  
National Standards ◽  
Legal Guardian ◽  
Department Of Homeland Security ◽  
The Us ◽  
Mexico Border ◽  
Customs And Border Protection ◽  
Physical Custody

“We saw no issues,” reports the Department of Homeland Security in a self-study of its practices for detaining children at the US–Mexico border, “except one unsanitary bathroom.” The system is working as it should; all is well. “CBP [Customs and Border Protection] facilities we visited,” the report summarizes, “appeared to be operating in compliance with the 2015 National Standards on Transport, Escort, Detention, and Search.” A footnote on page 2 of the September 2018 document defines the prisoners at these facilities, the “unaccompanied alien children,” as “aliens under the age of eighteen with no lawful immigration status in the United States and without a parent or legal guardian in the United States ‘available’ to care and [provide] physical custody for them.” Available is in scare quotes. This tic of punctuation discloses to us that the parents of these children have been arrested and removed. They are not available, and cannot take physical custody of their children, because they themselves are in physical custody. In a further typographical error, the word “provide” has been omitted: the children are without a parent or legal guardian in the United States “available” to care and physical custody for them. The dropped word turns “physical custody” into a verb and sets this new action, to physical custody, in tense relation to “care.”

Intersection Design and Decision–Reaction Time for Older Drivers

1997 ◽  
Vol 1573 (1) ◽  
pp. 68-71 ◽  
Author(s):  
David W. Naylor ◽  
Johnny R. Graham
Keyword(s):  
Reaction Time ◽  
Reaction Times ◽  
Older Drivers ◽  
Design Standards ◽  
Older Driver ◽  
The Past ◽  
Sight Distance ◽  
Stop Sign ◽  
Current Design ◽  
Design Value

Trends in automobile and roadway use have changed drastically over the past several years. Changes in the trends include an increase in the percentage of licensed drivers, annual miles driven, and an increase in the number of older drivers. Of particular concern is the increase in the number of older drivers and the question of whether the current design standards adequately meet the needs of the older driver. In this study, the perception-reaction time variable used in calculating intersection sight distance at stop sign-controlled intersections was evaluated. The current design value for the perception–reaction time is 2.0 sec, which has been used since the 1940s when the driving population was much younger. A field experiment was performed to determine an appropriate value for today’s driving population. Subjects were covertly videotaped as they entered two rural and two urban stop sign-controlled interactions. Mean decision–reaction times were determined for an older and a younger group of subjects. The older group, consisting of 104 subjects, averaged 69.3 years of age and had a mean decision–reaction time of 1.32 sec. A group of 104 younger subjects, less than 30 years of age, had a mean decision–reaction time of 1.24 sec. The 85th percentile decision–reaction time for the older group was 1.86 sec and for the younger group, 1.66 sec. Both times were less than the current AASHTO design value of 2.0 sec.

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