A Custom (air tight) Purchasing Specification

Most of you that read these posts are probably aware that, in addition to consulting work on overhead cranes and crane runways, I also do a considerable amount of work as an Expert Witness for legal cases involving cranes. As a result, my recreational reading is often hijacked by the latest edition of specs related to overhead cranes. Besides, reading spec books is a wonderful, drug free, solution for periodic insomnia. 

2015 Editions of the CMAA Specs

Last weekend I read the latest (2015 editions) of CMAA Spec 70 and CMAA Spec 74. After a lifetime in the crane business, I've paged through these specs a thousand times, but can't remember the last time I sat down and read them from cover to cover. The 2015 editions of Spec 70/74 seem to have more new material and changes than any revisions in recent memory. I decided to read them from front to back. Needless to say, my weekend was peppered with a number of involuntary naps.

Reading the Fine Print

I'm in the process of writing a comprehensive outline of both specs. Before diving into the outline, I felt compelled to write a post about something that I found that really surprised me, something I never read before. I was nearly knocked out of my reading chair on page 2 of the spec.

What could be such a shocking fact, found so early in the document? My "shock and awe" moment was the "Disclaimers and Indemnity" page. (FYI, for this post, I'll use CMAA Spec 70 (2015), but it is essentially the same as CMAA Spec 74). Let’s take this page apart, section by section.

Page 2, Section 2 Specifications, Paragraph 1:

“Users of these Specifications must rely on their own engineers/designers or a manufacturer representative to specify or design applications or uses. These Specifications are offered as information and guidelines which a user may or may not choose to adopt, modify or reject. If a user refers to, or otherwise employs, all or any part of these Specifications, the user is agreeing to the following terms of indemnity, warranty disclaimer, and disclaimer of liability”.

This paragraph is no surprise, a typical CYA paragraph.

Page 2, Section 2 Specifications, Paragraph 2:

“The use of these Specifications is permissive and advisory only and not mandatory. Voluntary use is within the control and discretion of the user and is not intended to, and does not in any way limit the ingenuity, responsibility or prerogative of individual manufacturers to design or produce electric overhead traveling cranes which do not comply with these Specifications. CMAA has no legal authority to require or enforce compliance with these Specifications. These advisory Specifications provide technical guidelines for the user to specify his application. Following these Specifications does not assure his compliance with applicable federal, state, and local laws or regulations and codes. These Specifications are not binding on any person and do not have the effect of law”.

1) Sentence one should not be a surprise. The CMAA is an industry association and not a governmental agency. It therefore has no legal authority. Conversely, it is the defacto standard of the industry, therefore carries a considerable about of weight but not a legal mandate.

2) Sentence two does not preclude anyone from building, selling or using a crane that does not conform to the spec.

3) Sentence three simply confirms that CMAA has no legal authority.

4) Sentence four reinforces that this spec is simply a "guideline". 

5) Sentence five protects the association from having to research state laws and/or a wing-nut interpretation by some local inspector or court.

6) Sentence six, reiterates that these specs are not binding and do not have the force of law.

Page 2, Section 2 Specifications, Paragraph 3:

“CMAA and MHI do not approve, rate, or endorse these Specifications. They do not take any position regarding any patent rights or copyrights which could be asserted with regard to these Specifications and do not undertake to ensure anyone using these Specifications against liability for infringement of any applicable Letters Patent, copyright liability, nor assume any such liability. Users of these Specifications are expressly advised that determination of the validity of any such copyrights, patent rights, and the risk of infringement of such rights is entirely their own responsibility”.

Everything after the first sentence are reasonable CYA sentences, but sentence #1 knocked me for a loop! 

"CMAA and MHI (the parent organization) do not approve, rate, or endorse these Specifications”.

What in the hell does it mean not to "approve, rate or endorse" your own specification? To have spent thousands of dollars (probably tens of thousands) and have the best and most experienced minds in the industry write two 100+ page specifications and then not to "approve, rate or endorse" them is the essence of “theatre of the absurd.” I'm sure, for some reason the legal counsel advised the CMAA/MHI to add this sentence, but it's indicative of a system that I'm embarrassed to be part of. 

Page 2, Section 2-Specifications, Paragraph 4:

“Caution must be exercised when relying upon other specifications and codes developed by other bodies and incorporated by reference herein since such material may be modified or amended from time to time subsequent to the printing of this edition. CMAA bears no responsibility for such material other than to refer to it and incorporate it by reference at the time of the initial publication of this edition”.

This is an important paragraph. The paragraph introduces a concept that's critical for the reader to be aware of. The term "incorporated by reference" is the ultimate spec writers ”gotcha."  CMAA 70 incorporates by reference over 25 other specs such as AWS 14.1, the National Electric Code and OSHA 29CFR Part 1910. Those three alone comprise a couple thousand sopoforic pages. (Author's note, I've waited over 30 years to use that word, it means, tending to induce drowsiness or sleep. Dad and Mom, that Notre Dame education paid off!)


So what's the point of the previous 997 words? Beside a rant against a broken legal system, it gets back to Caveat Emptor. Let the buyer beware. If the CMAA specs don't have the force of a legal mandate then the buyer has to protect themselves through writing a comprehensive specification of their own. It’s not good enough to simply say, “…I want a 30 ton, CMAA Class D Crane”. The buyer must specifically include the sellers must fully conform to CMAA Spec 70/74 as a requirement of the contract, and that’s just the beginning.

Additional questions include (but are not limited to)

Crane configuration:

  • Top running
  • Under running
  • Wideflange or Box Girders
  • Drive configuration
  • Cab or no-cab operation
  • Pendant or radio
  • Inverter control
  • Travel and lifting speeds
  • CMAA Duty Rating

Crane clearance:

  • Below the hook
  • Above the crane
  • Above the runway
  • Runways by who
  • Runway girders
  • Runway rail
  • Runway rail fasteners
  • Runway rail alignment
  • Runway conductor supply
  • Runway conductor installation
  • Runway power source 
  • Runway supports
  • Supports configuration
  • Supports supplied by
  • Supports installed by


  • CMAA
  • HMI
  • OSHA
  • ANSI
  • ASME
  • NEMA
  • AWS
  • NEC
  • Etc.


  • Approval process and prints required
  • Delivery Schedule
  • On-site storage/staging area
  • Unions/Non-union Installation Crews
  • Field measurements

If you don’t specifically address these points (and still others), there’s a good chance that an additional cost of your project will be legal fees, and those fees can approach the cost of the cranes!    

The Second Most Important Spec to Include:

One last note, the CMAA is really a crane spec and not a hoist spec. Hoist builders are not necessarily members of the CMAA. Hoists builders are members of HMI, the Hoist Manufacturers Institute. Their specs are ASME/HMI HST-1, ASME/HMI HST-2, ASME/HMI HST-3, ASME/HMI HST-4 and ASME/HMI HST-5. We'll go into the HST specs later.