COMMITTED TO SAFETY AND VALUE ENGINEERING - SINCE 1985
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David H. Glabe, P.E.

Qualified Engineer Needed?

By | Blog, Scaffolding, Seismic Engineering | No Comments

Various standards and codes require that an engineer’s services are to be used for certain scaffold designs and installations.  Is that really necessary?  After all, thousands of scaffolds are constructed daily without any input from engineers.  Furthermore, do these engineers need to be qualified engineers or will any engineer be acceptable?  And even furthermore, aren’t scaffolds only to be designed by a qualified person.  And even more furthermore, doesn’t the U.S. federal Occupational Safety & Health Administration, OSHA, have one regulation that requires a “registered professional engineer” and other regulation that requires a “qualified engineer?”  Is there a difference?  Can you be a qualified engineer without being a professional engineer and can you be a professional engineer without being qualified?  The answer is yes, yes, yes and yes.

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Hanging Out

By | Blog, Resources, Scaffolding | No Comments

The suspension rope supporting a temporary platform is the single most important element of a suspended scaffold. You may not agree with this—too bad for you. What if the rope breaks? The platform can only go down and if you are at a considerable height, the result will be mostly unpleasant. Understanding this suggests that we should probably be sensitive to the condition of the rope to which we trust our lives.
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Can Scaffolds Support This?

By | Blog, Resources, Scaffold Bracing, Scaffold Components, Scaffolding | No Comments

Spring is in the air, the birds are chirping and scaffolds are being built. Can life get any better? It used to be that contractors feared winter in the northern regions of North America. Cold temperatures, snow, wind and generally miserable conditions prompted owners and contractors to curtail outdoor activities. That was then; now construction charges ahead, fearless and courageous against even the nastiest of weather. Once again science and progress has prevailed! Improved, clothing, materials, equipment and methods allow construction to continue in any environment.
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FAQ’s ABOUT FALLS

By | Blog, Resources, Uncategorized | No Comments

A lot has been said about falls and fall protection. The U.S. Federal Occupational Safety & Health Administration, OSHA, has emphasized fall hazard awareness and increased enforcement of the fall protection regulations for years in the hope that deaths and major injuries due to falls in the workplace can be reduced. Manufacturers and suppliers are complementing the OSHA emphasis by offering a plethora of products that can be used to keep employees from falling. Or, more accurately, to keep employees from falling from heights to levels below in such a manner that they get injured or killed.
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This May Interest You

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While some rules and regulations are well known to the industry, sometimes the application of those regulations may be hidden in the complexity of the details. Here are a few confusing questions and equally confusing answers about scaffolding and the applicable standards.

If I construct a stairway utilizing scaffold components, and it is used to access a building under construction, does it have to be inspected prior to each workshift?  No it does not because it is not a scaffold. In this case, the stairway is a construction stairway and must comply with the requirements in 29 CFR 1926, Subpart X – Stairways and Ladders.  There are no requirements in Subpart X that requires the stairway to be inspected before each workshift.

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Plank Criteria

By | Resources, Scaffolding, Scaffolding Platforms | No Comments

There are two criteria that predict the safety of a scaffold platform.  One of the criteria involves the engineering properties of the scaffold unit.  The other criterion addresses the correct installation of the platform.  Correct installation includes proper support, correct positioning to limit spaces between platform units, and the minimum width of the platform.

The Federal Occupational Safety and Health Administration, OSHA, and other agencies, set forth the minimum standards for the installation and use of platform units.  For example, regulations address the minimum and maximum overhang of platform units, the allowable deflection, the space between units, and the distance from the edge of the platform to the work surface and the guardrail system.  These regulations are in the subsection on platforms, 29CFR1926.451(b), and are quite specific.  The regulations address all platforms, including solid sawn wood plank, laminated veneer lumber (lvl), metal fabricated decks, and platforms constructed of structural members and sheathing such as plywood.  These specific regulations ensure that the platform you construct will stay on the scaffold, will be large enough so you won’t fall off the platform, and won’t have any openings that you may fall through.

Engineering properties also predict the safety of the platform.  For manufactured platforms, such as aluminum decks and laminated veneer lumber, the manufacturer indicates the capacity of the product.  For solid sawn plank, determining the capacity is not as straightforward due to varying factors.  These factors include the dimensions of the plank, the specie of tree, what part of the tree is being used, and if the wood has any damage.  How in the world do you determine if the plank is strong enough?  Fortunately, you have help!  Qualified engineers can determine the strength of the plank you are using if the dimensions, the specie of tree, and the quality of the wood are known.  The engineer will also need to know the span of the plank, that is, the distance between supports.  While you can give the engineer the dimensions and span of the plank, the type and quality of the wood is another story.  Unless you cut the tree down yourself, you probably won’t be able to tell if the wood is pine or poplar.  And unless you have learned how to grade lumber, you won’t know if the wood is any good.

How, then, is the grade of the wood determined?  Qualified, trained lumber graders are one method used by lumber mills to determine the strength of wood.  These individuals are trained to determine the various strengths of wood that will come from a tree.  Factors used to determine strength include such things as density (how many rings per inch), the straightness of the grain, and the frequency of knots.  Straighter grain, higher density, and fewer knots will result in a strong piece of wood.  On the other hand, frequent knots and low density will result in a low strength piece of wood.

The engineer relies on the ability of the grader to do his or her job correctly.  The engineer also relies on the accuracy of the stamp to determine precise information for you to use.  The bottom line here is that the information in the grade stamp dictates the accuracy of the engineer’s calculations.  Of course, this information will only be accurate if the plank you use has been graded by a qualified grader, using recognized standards.  If the wood is not as good as the grade stamp indicates disaster will surely follow.

For typical situations, it is recommended that only Scaffold Grade plank be used since this will enhance safety on your scaffold project.  Scaffold Grade plank is a very specific grade of lumber that has a very high strength compared to other commonly found lumber on a construction project.  However, if you choose to use a plank other than scaffold grade, it must be engineered for proper use.  This is the only way you will be safe and in compliance with the regulations.

Do not take chances with solid sawn wood plank.  A grade stamp from a recognized grading agency is your guarantee of accuracy.  High strength lumber is not cheap.  Neither is a worker’s life.  If the board breaks, there is no back-up.

CALIFORNIA MAST-CLIMBING WORK PLATFORMS – How to be Compliant in California

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Many contractors, including mason, sealant, waterproofing and restoration contractors, frequently use aerial work platforms to reach their work. Besides aerial work platforms such as boom lifts and scissors lifts, mast-climbing work platforms (see photo) are becoming more common due to their large working platforms and relatively quick assembly. CalOSHA describes a Mast-Climbing Work Platform (MCWP) as “a powered elevating work platform or platforms, supported on one or more vertical masts, for the purpose of positioning personnel, along with necessary tools and materials, to perform their work.”
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Safety is Not My Goal!

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Safety is not my goal. You read that right—Safety is NOT my goal. Have you ever noticed the sign on the back of pick-up trucks (usually construction company trucks) that state that “SAFETY IS MY GOAL.” I strongly recommend that when you see one of those trucks, do not pass the truck; I repeat, do not pass the truck. It’s obvious that if the driver is aiming towards safety, he just hasn’t gotten there yet. Better to stay behind him and see where he heads. Who knows, maybe there’s a sale at the local home improvement store and he’s planning on buying a bucket or two of safety.
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Should Anchors Be Broken?

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Anchors are an essential component of any fall protection and scaffold rigging system. In fact, they are so essential that state and federal regulations, not to mention consensus standards such as the American National Standards Institute (ANSI) standards, require regular inspection and testing of anchors to ensure adequacy in the event that they are needed to arrest a fall or arrest equipment failure.
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How Did You Get Up There?

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If you want to get from here to there, safe access is critical. This is especially true if you want to get to an elevated platform such as a scaffold platform. It is also true for other situations including structures such as shoring and formwork. Since shoring, that is the equipment to temporarily support concrete […]

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