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Magnitude of the Problem and Nail Gun Trends

Several major studies have examined nail gun injuries in construction workers. When examining construction data for nail gun injuries, researchers usually looked more specifically at the following groups and activities because of substantial nail gun use and increased exposure compared to general construction:
• Residential construction
• Carpenters
• Drywallers
• Framing
• Rough carpentry
• Roofing activities

In Dement et al., [1] 66% of nail gun injuries were concentrated in the framing and sheathing stage of operation, followed by roofing, and then exterior siding and finish carpentry work. These findings were also mirrored by other research, and coincide to observable aspects on the jobsite such as: [4, 5]
• Framing nailers are typically larger and more powerful
• Nailing done in this stage of construction requires awkward positions
• Work at heights
• Handling and balancing loads is common
• Jobsite is less organized than later in the building process
• Nailing of roof and floor sheathing is usually done with bounce nailing

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Employees are Commonly Exposed to Heights and Numerous other Hazards During the Framing Process

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Poor Housekeeping During the Framing Stage of a Residential Jobsite

Baggs et al., [5] did an initial study in Washington state on nail gun injuries and rates using workers’ compensation claims:
• 79.8% of all the nail gun injuries reported (3616) resulted in medical-only claims
• Approximately 20% of claims resulted in indemnity payments

Dement et al., [1] conducted a study based on Ohio and North Carolina residential construction workers to determine their rates of nail gun injury. The study found the following rates and results:
• NC carpenters had a 0.91 per 200,000 hour nail gun injury rate
• OH carpenters had a 1.32 per 200,000 hour nail gun injury rate
• 2.06 cases per 200,000 hours for wood framers overall
• 0.66 cases per 200,000 hours for interior carpenters overall
• Lost time cases in NC made up 25.5% of claims,
• Lost time cases in OH were 8.3% of claims
• In OH, workers ages 20-24 years had a higher rate of injury, 0.69 per 200,000 hours
• 4% of injuries were due to nail guns out of all claims in the overall population
• Punctures accounted for 80-89% of all nail gun injuries in the study population

Lipscomb et al.,[4] did a large scale, active surveillance study involving union residential carpenters and drywallers. The study included 5137 carpenters who worked with one of 20 contractors (St. Louis, Missouri area), and accrued over 9,346,603 hours during the course of the study. Two experienced, trained, union journeymen carpenters actively surveyed the study population about nail gun injuries, capturing detailed information on the nature and circumstances surrounding the nail gun incident. Many more injuries were captured due to the active surveillance method than by the use of injury log or workers’ compensation claim reporting. This study yielded very important information on nail gun injuries:
• Of all the injuries reported, 14% were due to nail gun injuries.
• Over 20% of the struck-by injuries on the jobsite were from nail guns
• The majority of injuries penetrated hands or fingers
• Apprentices had a 3.7 per 200,000 hour rate of injury
• Journeymen (more experienced and older) had a 1.2 per 200,000 hour rate of injury

In a later study by Lipscomb et al., [6], focusing on just on apprentices, results showed some important nail gun trends specific to this younger and less experienced group of workers.
• 25% of apprentices reported a nail gun injury within a year of the study
• 12% of injuries were caused by another using the gun and injuring the apprentice
• Overall injury rate for these apprentices was 10.3 per 200,000 hours
• This rate (10.3) was almost three times as high as calculated in previous study (3.7)

An overall trend among all the studies was that hands and fingers accounted for the majority (up to 66% reported in studies) of nail gun injuries[1-3, 6-8]; but, incidences of paralyzing spinal cord injuries, organ perforations, eye injuries causing blindness, fractures, brain damage, severe heart and lung injuries, and even death have been reported. [1, 3, 4, 6-9] After hands, the most frequent sites of injuries were the foot, knee, toe, eye, thigh, and wrist. [1, 5] Nail guns are a definite source of jobsite injuries, and especially are a major contributor to struck-by injuries on the jobsite.

Nails fired from a nail gun can have the penetrating characteristics and abilities of bullets, and are very similar to low velocity gun shot wounds. [9, 10] They also have the projectile free-flight speeds of over 200 mph. [3] Attention to safety and proper work practices is very important, and the primary safety mechanism on a pneumatic nail gun is the trigger mechanism working in combination with the contact element in the nose of the gun to prevent accidental discharge of a nail. [6] The above studies also show that the majority of these puncture injuries were caused by bypassed and/or inoperable safety mechanisms on the guns. [1]