Wind Turbine Tower Elevators, Part I

Confusion over wind turbine tower conveyance code jurisdiction is explored in this first article in a series on the topic.

The elevators currently installed in wind turbine towers do not comply with ASME A17.1/CSA B44 Safety Code for Elevators and Escalators (hereafter A17.1^[1]), the recognized national code for Special Purpose Personnel Elevators (SPPE) in North America. There are two avenues of obtaining elevator certification in jurisdictions enforcing A17.1, requirement 5.7: apply for variances for the non-conforming 5.7 requirements or obtain certification with A17.7/B44.7, the ASME A17.7 Performance Based Safety Code for Elevators^[2] (hereafter A17.7).

Confusion over conveyance jurisdiction was primarily the result of wind turbine towers being remote; another source of confusion is that conveyances originated in Europe, where there is not a SPPE norm (code) as there is in North America. Once lifts migrated to North American wind turbine towers, they were out of sight from elevator AHJs. Most AHJs were surprised to learn these devices were installed without their knowledge. When it became known, AHJs who enforce A17.1, requirement 5.7 demanded these conveyances be permitted and inspected. Non-conforming code issues then needed to be evaluated and explained, and variances issued after review.

A new section of A17.1 has been drafted to provide designers and inspectors the code for these conveyances. It is undergoing the consensus standards writing process, with the hope of publication in 2013.

Wind farm developers and owners began discovering the jurisdictional landscape and have several questions, which is the purpose of this article.

SPPEs

A jurisdictional misunderstanding occurred in 2009, when the service lift segment of the wind industry believed the conveyances were not elevators, but something else (e.g., service lifts, manlifts, suspended access devices, etc.). This article helps clarify the issue by providing details about the efforts of Avanti, American Wind Energy Association (AWEA) and American Society of Mechanical Engineers (ASME). Until recently, most wind industry elevator companies relied on claims that many standards and codes applied and that they were in compliance with them. These conveyances originated in Europe, and, as is typical, there are major differences between European and North American codes.

While there is not presently a European Norm for these conveyances, there is a general reliance on EN 1808, the European Norm for “Suspended Access Equipment,” a code most analogous to ANSI A 120.1: Safety Requirements for Powered Platforms and Traveling Ladders and Gantries for Building Maintenance and CSA-Z271: Safety Code for Suspended Elevating Platforms, devices commonly seen on the sides of buildings in North America known as window washing platforms.

In 2008, wind industry elevator companies began meeting with jurisdictional resistance when asked to comply with ASME A17.1: Special Purpose Personnel Elevators. This resulted in claims of conformance to a myriad of other codes and standards in error as the people selling these conveyances, with little or no code experience, cited bits and parts of various unrelated codes and standards and claimed safety was being achieved with those various requirements.

This was faulty thinking, because the requirements of any code or standard are based on many factors, mainly the environment and inherent hazards of the conveyance. A hazard assessment based on the foreseeable use and, ultimately, the codification of the corrective actions and mitigations is required. Taking a requirement from a related code or standard can be dangerous when a conveyance or device is used in another environment. These early unconvincing arguments were challenged when the presence of the conveyances was discovered by AHJs.

An elevator is defined in the building codes by reference to ASME A17.1/CSA B44^[3] and CSA B311 as a hoisting and lowering mechanism, equipped with a car that moves between two or more landings.

ASME A17.1-2010/CSA B44-2010

Section 5.7: Special Purpose Personnel Elevators

In jurisdictions not enforcing NBCC, requirement 5.7 applies to elevators permanently installed in a wide variety of structures and locations to provide vertical transportation of authorized personnel and their tools and equipment only. Such elevators are typically installed in structures such as grain elevators, radio antennas and bridge towers, underground facilities, dams, power plants, and similar structures where, by reason of their limited use and the types of construction of the structures served, full compliance with Part 2 is not practicable or necessary.

Requirement 5.7 applies to SPPEs having a traction, winding drum, screw, or rack-and-pinion driving machine.

CSA B311-02

Safety Code for Manlifts

1. Scope

1.1 This standard specifies minimum requirements for the design, construction, installation, operation, inspection, testing, alteration and maintenance of permanently installed manlifts for the vertical transportation of authorized personnel and, where authorized, their tools and equipment. Such manlifts are typically installed in structures such as grain elevators, radio antennae, bridge towers, underground facilities, dams, power plants, pulp mills and similar structures.

Wind turbine elevators meet every criterion of A17.1/B44 by being an elevator and requirement 5.7 of A17.1/B44 by being a SPPE. They are permanently installed in a “similar structure,” used for transportation of authorized personnel and their tools and equipment, and by limited use and construction limitations of the structure served, should not have to conform to all of the A17.1 Part 2 requirements.

With the relatively new existence of wind turbine elevators in North America and its unique environment, A17.1 language had to be drafted to differentiate them, even from requirement 5.7, because of the unique environment of a wind turbine tower. In January 2009, with the affirmation of American National Standards Institute (ANSI), the A17 Standards Committee voted to create a new Part 5 requirement, 5.11, with one requirement; that these devices conform to A17.7/B44.7. Next, the committee voted to draft requirements for wind turbine elevators, because the expected high number and safety concerns demanded a prescriptive code. Since then, an A17 project team of industry experts has drafted and balloted requirement 5.11. Extensive work has been done with both wind and elevator industry personnel to make a concise, relevant and useful code to ensure a minimum level of safety for these elevators.

It is fundamental to safety to provide engineering guidance in the form of a code or standard for the design, maintenance, inspection and testing of special purpose personnel elevators. When the A17 Standards Committee elected to draft the code in early 2009, AWEA, also an ANSI accredited standards writing body, was in the position to participate in this undertaking or let ASME promulgate the code. In late 2009, AWEA announced that A17.1, requirement 5.11 is the code to apply to wind turbine elevators. Currently, requirement 5.11 has been drafted and gone to ballot and it is hoped to be ready for publication in the 2013 edition of A17.1. Once approved for publication, it will become the document used by all AHJs who enforce the requirements of A17.1, section 5.7.

Explanation of Jurisdictions in North America

Many owners have asked, “How did this happen?” and “How did the regulatory bodies (AHJs) somehow find a way to increase the cost of permits, inspections and reinspections?” In an era of seeming over-regulation, the reality is there was confusion early on and, now that the wind industry is aware of elevator AHJs, compliance with the A17 code and enforcement of the code by AHJs should be considered the proper procedure. When any conveyance moves people, it must be manufactured and installed with a higher level of care. This has always been the case with elevators and it should be so with wind turbine elevators as well.

Jurisdictions are arranged in North America by state and province. In some states, “Home Rule” laws allow larger cities and counties to act as their own jurisdiction, in addition to the parent state. Numerous states have a state code, which the local jurisdictions must enforce. With that in mind, there are approximately 140 AHJs in North America. Virtually every state, province, large county and large city adopts a building code by statute or regulation that references the elevator sub-code (A17.1) or an elevator code separately from the building code.

The model building code references other model codes (its sub-codes) for all regulated systems and subsystems in structures and buildings. The most used building code in the U.S. is the International Building Code (IBC), which references A17.1 for elevators. The National Building Code of Canada (NBCC) references the A17.1/B44 elevator code and CAN B311 for manlifts, the analogous code to section 5.7 in A17.1 Special Purpose Personnel Elevators.

Since there are 64 states, provinces and territories, numerous counties and cities with their own safety or building departments, and all are free to adopt any edition or addenda of a code and modify or except specific requirements, it is not uncommon to have differing code requirements among the jurisdictions. These differences are typically based on the local experience due to local conditions such as hurricanes or harsh weather, as well as staff experiences, past practices, vestigial laws and regulations, legislative cycles, lobbying efforts, and a fear of rising building costs with the adoption of newer editions of codes by lawmakers and stakeholders.

The timing of legislative or regulatory adoption contributes greatly to the diversification of adopted editions of codes. Some legislatures only meet bi-annually, and some work full time. Generally, building codes are not of top importance for legislatures and require public lobbying in some cases to get later editions passed through legislature or regulatory adoption. This is changing somewhat as the model code includes auto adopt language that ensures the jurisdiction adopts the latest editions, but presently this standard is only in a handful of jurisdictions. This means that while having a national standard seems logical, the diversity of adopted editions is large, and what is required in some jurisdictions may be disallowed in others. It can be very confusing.

The building code and regulatory bodies specify an AHJ for the respective sub-codes. There are generally government departments for inspections. These departments are headed by the chief inspector (or similarly titled person) who manages the respective inspections, plan reviews, final inspections, accident investigations, training for their personnel, etc. for that particular sub-code. These are powerful positions and are the first line of consideration and appeal when it involves compliance issues, new designs or new technology. This arrangement also assures differentiation between the building trades with a specific department in charge of the specific sub-codes. Due to cost, many departments may do double duty; it is not uncommon for the elevator inspectors to also inspect boilers, amusement rides and ski lifts in some jurisdictions. 

This separation of codes is ensured by the scope of each sub-code. This ensures that the electrical inspector does not inspect conveyances not within the scope of his/her sub-code even though there are extensive electrical components in an elevator. There are typically AHJs for building, electrical, elevator, plumbing, mechanical, fire, and life safety codes. Therefore, it is vital that the scopes of the codes are correctly recognized to eliminate the possibility of inappropriate requirements placed on a system by the wrong AHJ, and that all systems have a code regarding the design, inspection and testing relevant to the regulated system. It also assures that conveyances must be identified and conform to the applicable requirements and not pieces and parts of several codes.

In jurisdictions, there are also elevator safety review boards (or committees of different names) who meet to rule on waiver or variance requests, govern the administrative procedures for issuance of permits, make recommendations to administrators on adoption of codes and other administrative duties. In most cases, the chief inspector advises the boards on technical matters. Most elevator safety boards consist of non-elevator people, though there will be a cross-section of appointed engineering, architectural, fire safety and accessibility experts who can then, as a group, make decisions based not just on the actual elevator question, but on its impact on an entire project, an environment or its jurisdictional policies.

AHJs make the final ruling on the regulated conveyances, but the legislative bodies may exclude some industries or some requirements altogether. Hence, there are some AHJs who omitted enforcement of wind turbine tower elevators; in reality, they have been relieved of regulating them altogether. Colorado, Texas and Oklahoma, for example, exclude “Industrial Facilities” from conformance to A17.1. There may have been good reason to do this in the past, but with the expected number of wind turbine towers increasing throughout North America, there may be change even in those jurisdictions.

Initial Confusion and Going Unnoticed

In mid-2008, thousands of wind turbines had been erected, many with elevators. This led to a belief among wind turbine manufacturers, owners and elevator manufacturers that there were no requirements for elevators. This was likely due to the tower’s remote location, some local legislative requirement for exclusion of “industrial facilities” from compliance to A17.1 and the wind industry elevator manufacturer’s being from Europe and unfamiliar with North American codes for SPPEs. Therefore, thousands of conveyances were installed as designed in Europe without elevator AHJ knowledge and without any challenge to their non-compliance with elevator safety requirements.

In order of number of installed turbines, Texas has the largest installed base of wind towers, followed by Iowa and California. With no exclusionary legislation and a smaller area with a higher density of elevators and more elevator inspectors, Iowa, led by Chief Inspector Jim Borwey, discovered these conveyances and ultimately required conformance to A17.1 or A17.7 with a law. This came as a shock to the wind industry elevator manufacturers, installers and owners at the time, but gradually, they complied with the law and have participated on the development of a new section 5.11 of A17.1.

If wind turbines had been more of an urban product, the elevator authorities would have given the wind industry earlier notice of the requirements than they experienced. Another contributing factor was that elevator personnel were not installing these units, so the opportunity to have the correct direction pointed out was missed.

Another factor was that the State of California knowingly disregarded its adopted code (A17.1-2004, section 5.7) and made a determination that it did not wish to have wind-turbine elevators under their jurisdiction. It can only be speculated as to why that occurred, though costs of inspection were suspected as the primary reason. Eliminating the need to add thousands of inspections per year to a jurisdiction with a severely taxed inspection department was the easiest choice to make by the principal engineer (chief inspector) at the time. This was being reevaluated by the State of California at the time of this writing.

Other examples of the legislative nature of compliance occur in Texas, Oklahoma and Colorado where “industrial facilities” are exempt from compliance to A17.1 by law. The specific exclusions were likely on the merits of there not being a significant number of units in total in these states and that regulating the conveyances in the industrial facilities^[6] met with industry resistance to the legislature so as to reduce the costs to the owners and operators of these facilities. These lobbying efforts were successful. With the expectation of the wind turbine tower elevators numbering in the thousands, the Texas Department of Licensing and Regulation and the Texas Commission and other legislative bodies might consider modifying this requirement to include these elevators in the future.

Scope Questions

At the October 2008 AWEA Health and Safety Workshop in Denver, one wind industry elevator manufacturer made claims of conformance to several codes and standards. On another’s website, there is a list of standards and codes they purportedly conformed to, including A17.1. Part II of this article will detail the scopes of all North American standards that have been referenced by all wind industry elevator manufacturers, with pictures of the named devices. The pictures and their scopes will show the appropriate applications, and it is obvious that these conveyances are not wind turbine tower elevators. The use of a traction climbing driving machine could have caused some of the incorrect determinations, but not all. Typically these driving machines are only used in temporary installations such as window washing platforms. These driving machines are used in the elevator industry as temporary construction hoisting platforms, as well.

References

[1]       The code in the U.S. was A17.1 and in Canada B44 until 2007, when the codes harmonized. For this article, the term A17.1 will be used knowing there are some jurisdictions still on a pre-2007 code, some on later codes. It is intended that the reference is a placeholder for whatever adopted code is in jurisdiction.

[2]       In jurisdictions using any previous edition of A17.1 prior to A17.1-2007, A17.7 may not be available for use.

[3]       Section 5.7 has not changed significantly in the code since 2000. In this article, the reference to A17.1/B44 is used throughout because it is the name of the current edition (2010 of code), it should be read as synonymous to A17.1, the tile of the code prior to harmonization with B44 in 2007.

[4]       Reprinted from ASME A17.1-2000, by permission of the American Society of Engineers. All rights reserved. No further copies can be made without written permission.

[5]       The National Building Code of Canada specifies CSA B311 as the applicable code for manlifts, it is the analogous code and is presently being harmonized with A17.1 Section 5.7.

[6]       Texas Health and Safety Code, Title 9 Safety, Chapter 754, Section 754.014. Standards Adopted by Commission. This subchapter does not apply to equipment in an industrial facility, or in a grain silo, radio antenna, bridge tower, underground facility, or dam, to which access is limited primarily to employees of or working in that facility or structure.

Note: In reference to the code, the information was reprinted from ASME A17.1-2010, by permission of the American Society of Mechanical Engineers. All rights reserved. 

Also read: Wind Turbine Tower Elevators, Part II