ANSI’s Nail Gun Safety Standard ignores safety research, ANSI process criticized

You’ve probably seen on-line the grim photos showing a construction nail embedded in a person’s skull or hand. The culprit: nail guns. In particular, those with “contact actuation triggers.” An estimated 37,000 pneumatic nail-gun related injuries are treated in US emergency rooms every year, with slightly more than half being work-related. Nail guns are the leading cause of tool-related injuries in the US construction industry that result in hospitalization. As researchers who study nail gun safety wrote in the March 2015 issue of Professional Safety:

“Before pneumatic nail guns were available, nail puncture injuries on a construction site typically occurred when a carpenter or other tradesperson stepped on a nail protruding from a piece of lumber. Carpenters did not accidentally drive nails into their own bodies or that of a coworker with repeated strikes from a hammer. However, such injuries became more common when pneumatic nail guns were introduced to drive nails at a high speed to go through hard materials.”

So when revised nail-gun safety standards were finalized earlier this year by the American National Standards Institute (ANSI), the public health community should have cheered, right? A new updated standard designed to reduce injuries caused by nail guns is a good thing, isn’t it?

Not necessarily so, say Hester Lipscomb, Ph.D. of Duke University Medical Center, Mark Fullen Ed.D. of West Virginia University and Matt Gillen, MS (formerly with the National Institute for Occupational Safety and Health), the leading researchers and safety and health professionals following on nail gun safety. The three participated in the ANSI process, raised concerns about its conduct, and continue to press ANSI to answer fundamental questions about how the new standard was developed.

Here’s a bit of background:

ANSI staff do not write the standards adopted by the organization, but they establish the rules and procedures for “directly and materially affected parties” to develop a consensus standard. In the case of nail guns (formally known in the tool manufacturing industry as “portable compressed-air-actuated fastener driving tools”), the sponsoring organization was the International Staple, Nail and Tool Association (ISANTA). The association describes itself as:

“an international organization of premier power fastening companies involved in the design, manufacturing, and sales of pneumatic and cordless tools and the fasteners they drive.”

ANSI is responsible for overseeing ISANTA’s process for developing the safety standard and ensuring it conforms with ANSI’s policies.

The previous nail-gun safety standard, referred to as SNT-101, was long overdue for a revision. ANSI rules for safety standards (in contrast to those addressing matters such as interoperability or quality) indicate such standards should be revised on a five-year schedule. SNT-101 was originally adopted in 1983, but has only been revised three times. That’s a hint that the ANSI process and/or its relationship with ISANTA is suspect. But it gets worse.

ANSI has a 30-page document describing the due process requirements for groups who develop the standards. High on the list of requirements is “lack of dominance” and “balance.” Like the five-year schedule, there are additional special procedural requirements for safety standards. One of the special requirements is:

“no single interest category constitute more than one-third of the membership of the consensus body.”

When one looks, however, at the make-up of group convened by ISANTA to develop the nail-gun safety standard, it widely misses that mark. As Lipscomb, Fullen and Gillen write in a critique to ANSI’s Executive Standards Council, ISANTA’s standard-development group was dominated by manufacturers and construction industry trade associations.  ANSI’s procedures for safety standards explicitly state:

“where the standards activity in question deals with subjects of special interest to the American worker, such as products used in the workplace, an appropriate user participant is a representative of labor.”

But ISANTA’s committee hardly had any worker or consumer representatives—there wasn’t a single consumer representative—not even a representative from the Consumer Product Safety Commission.

Here’s how Lipscomb and colleagues describe what happened:

“We were initially puzzled because ISANTA proposed a sheet metal worker to participate…This was not an appropriate choice given that the sheet metal trade does not typically use nailers or fastener tools. This was the second time that ISANTA planned to use a single worker representative from that trade that does not typically use the relevant tools.”

“[We] communicated with ISANTA by email to inform them that the carpenters were the most appropriate labor group to be involved in the process. We also informed the carpenters union about the revision of SNT-101 after receiving no response from ISANTA to our emails. Based on information available to us, we understand that representatives of the St. Louis Council of Carpenters contacted ISANTA asking to participate. They were initially told by ISANTA they could participate as non-voting ‘observers.’ Mr. Terry Nelson, Executive Secretary-Treasurer of the Carpenters District Council of Greater St. Louis and Vicinity then protested by letter to ISANTA and as a result a carpenters’ representative was included in the consensus body.”

“This sequence of events suggests to us that ISANTA was not receptive to meaningful labor participation, did not actively seek it, nor will they do so in the future. It is critical for ANSI to recognize that participation by a single labor union representative (two percent of the canvass body) does not suffice as credible balance when employer representatives account for 25 percent.”

Failing to comply with ANSI’s requirements for committee make up is bad enough, but other defects in the process make matters worse. The new version of SNT-101 ignores more than a decade of research on nail gun safety. That’s right, the new ANSI safety standard for nail guns rejected the best available body of scientific evidence.

There’s plenty in the scientific literature on injuries related to nail guns, as well as injury risk differences depending on the trigger system of the tool (e.g., here, here, here, here.) A sequential actuation trigger (SAT) only allows a nail to be discharged when the safety tip is depressed and held, and then the trigger is squeezed. A contact actuation trigger (CAT) allows the operator to squeeze the trigger and repeatedly bump the tip to shoot multiple nails.  Users—even experienced ones—face twice the risk of injury when using a CAT nail gun.

The new SNT-101 fails to require SAT or even a requirement that an SAT be made an available option for all nailers. On top of that, two types of popular pneumatic fastener tools (i.e., coil nailers and the general category of “production application” nailers) are exempt from SAT requirements. This alone makes the new SNT-101 unacceptable as a safety standard.

Why does it matter? Manufacturers of these tools want to market them as meeting the most current ANSI safety standards. They want to brand themselves as having the highest concern for consumer and worker safety. They want to shield themselves from liability for users’ injuries by pointing to their tool’s conformance with ANSI’s SNT-101. But if SNT-101—an alleged safety standard—ignores the current body of scientific evidence, and was developed through a process dominated by those with a vested interest in a weak (rather than robust) safety standard, where does that leave users of nail guns?  With the tool manufacturers laughing behind their backs, while they have nails protruding through body parts.

It also matters because this isn’t just about nail guns and ANSI’s SNT-101. There are many existing voluntary safety and health consensus standards. What occurred with SNT-101 begs the question: “how well does ANSI address and oversee occupational and consumer safety and health standards?”

Lipscomb, Fullen, and Gillen participated in ISANTA’s ANSI-approved process and found plenty of critical flaws. To their credit, they’ve posed questions to ANSI about its process for developing safety standards, and offered 24 recommendations to reform the it. I’ll be looking at ANSI safety standards with even greater skepticism until I hear the organization is taking seriously its oversight of groups that are developing ANSI safety standards.



  1. #1 Jazzlet
    December 17, 2015

    A sorry state of affairs.

    There are no links to studies on nail gun injuries or comparisons of trigger type.

  2. #2 Celeste Monforton, DrPH, MPH
    December 17, 2015

    I apologize. I added links to the “(e.g., here, here, here, here)”

  3. #3 Nancy
    May 1, 2016

    Thanks, here is some information about nail gun.

  4. #4 Charles R. Hotze III
    September 25, 2017

    Respectfully, Dr. Monforton – if you only knew the intense, complex discussions and concerned industry review – amounting to many hundreds of hours dedicated by ISANTA members – to this topic, then I believe you would retract your ill-chosen comment here below:

    …where does that leave users of nail guns? With the tool manufacturers laughing behind their backs, while they have nails protruding through body parts.

    Deeply concerned and caring individuals make up these volunteer committees of ISANTA.

    Characterizing these trustworthy and independent thinking men and ladies of ISANTA in such a way ~ implies total one- sided thinking which is often seen by those whose credentials include “Professional Lecturers.”

  5. #5 Celeste Monforton, DrPH, MPH
    September 25, 2017

    Mr. Hotze,
    Thank you for sharing your views. I continue to think that the make-up and process used by ANSI resulted in a huge missed opportunity to protect workers and the public from nail-gun injuries.