Powder actuated fastening tools

You must test each powder actuated fastening tool every day before loading it, and immediately remove any tool that is not working properly from service until it is repaired. See the specific requirement in 1915.135(b)(1).

• Test daily before loading to confirm safety devices function.
• If the tool fails the test, stop using it and take it out of service until repaired.
• Document repairs and re-test before returning the tool to service to ensure the safety devices are working.

No. Powder actuated fastening tools must not be used in explosive or flammable atmospheres. See 1915.135(b)(2).

• If your work area has flammable vapors, gases, or dusts, do not use powder actuated tools until the area is made safe (ventilated, purged, or otherwise controlled).
• Follow your site’s hazardous-atmosphere procedures and consult a competent person if unsure.

You must use the type of shield or muzzle guard that is appropriate for the specific use and tool being operated. See 1915.135(b)(3).

• "Appropriate" means the guard recommended by the tool manufacturer or one that prevents flying fragments and protects the operator’s hands and bystanders for that particular task and material.
• If you’re unsure which guard to use, follow the manufacturer’s instructions and have a competent person confirm the selected guard is correct.

You must not drive fasteners into very hard or brittle materials such as cast iron, glazed tile, surface hardened steel, glass block, live rock, face brick, or hollow tile. See 1915.135(b)(4).

• Use other fastening methods or consult a competent person if you must attach to these materials.
• Driving into these materials can cause the fastener or substrate to shatter and create flying fragments or missed anchorage.

You may drive fasteners into soft materials only if those materials are backed by something that prevents the pin or fastener from passing completely through and becoming a flying missile hazard. See 1915.135(b)(5).

• Always place a backing (block, plate, or similar) behind soft materials when using powder actuated tools.
• If backing isn’t feasible, use a different fastening method to avoid fasteners penetrating and creating hazards.

You must follow these minimum distances unless a special guard, fixture, or jig is used: do not drive fasteners into brick or concrete within 3 inches of an unsupported edge or corner; do not drive into steel within 1/2 inch of an unsupported edge or corner; and when fastening other materials (for example, a 2×4 to concrete) do not use fasteners larger than 7/32 inch shank diameter and do not drive within 2 inches of an unsupported edge or corner. See 1915.135(b)(6).

• If you must work closer to an edge, use a special guard, fixture, or jig to support the area.
• These distances reduce the chance of cracking, spalling, or failure of the workpiece and reduce flying fragments.

No. Fasteners must not be driven through existing holes unless you use a positive guide to secure accurate alignment. See 1915.135(b)(7).

• A positive guide (bushing, sleeve, or jig) prevents the tool from slipping and keeps the fastener aligned.
• Using a guide reduces the risk of misfires, ricochets, and improper anchorage.

You must not attempt to drive another fastener into a spalled area caused by an unsatisfactory fastening. See 1915.135(b)(8).

• Spalled or damaged material can’t reliably hold another fastener and can produce flying fragments.
• Move to a sound area at the required edge distance or repair/replace the damaged material before fastening.

Employees using powder actuated tools must be protected by appropriate PPE in accordance with Subpart I of Part 1915, and employers are generally required to provide required PPE at no cost to employees except for limited exceptions. See 1915.135(b)(9) and OSHA's employer payment guidance on PPE (see the Letter of Interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2014-11-13).

• Typical PPE for powder actuated tool use includes eye protection, face protection, and hand protection; select devices consistent with 1915.153 criteria for eye/face protection and manufacturer recommendations.
• OSHA’s final rule on employer payment for PPE requires employers to pay for required PPE unless an exception applies; see OSHA’s Letter of Interpretation on PPE payment methods for details.
• Document PPE selection, training, and provide replacements when PPE is worn from normal use.

Operators must be thoroughly instructed by a competent person about the safety requirements in paragraph (b) and the safe use of the tools before they are allowed to use them. See 1915.135(c) and the OSHA letter explaining the role and authority of a competent person at https://www.osha.gov/laws-regs/standardinterpretations/2016-04-18.

• A "competent person" is someone capable of recognizing hazards and specifying needed protections; that person may determine training content and confirm operator competence.
• Keep records of training and the identity of the competent person who provided instruction.

Before using a tool, the operator must inspect it to ensure it is clean, all moving parts operate freely, and the barrel is free from obstructions. See 1915.135(c)(1).

• Check for dirt, buildup, bent or damaged parts, and any loose fasteners on the tool.
• If you find anything unusual, tag the tool out and notify a supervisor or competent person before use.

If a tool develops a defect during use, the operator must immediately stop using it and notify their supervisor. See 1915.135(c)(2).

• Do not attempt to continue using a defective tool.
• Ensure the defective tool is taken out of service and repaired by a qualified person before returning it to use.

Tools must not be loaded until just prior to the intended firing time, and a loaded tool must not be left unattended. See 1915.135(c)(3).

• Load the tool only at the work surface and immediately before firing.
• If you must step away, unload the tool first and secure it so unauthorized persons cannot access it.

Operators must never point the tool, whether loaded or empty, at any person, and must keep their hands clear of the open barrel end. See 1915.135(c)(4).

• Treat every tool as if it could fire; keep fingers away from trigger until ready to fire and keep hands clear of the muzzle.
• Use safe positioning and work aids (e.g., support stands or fixtures) to avoid placing hands near the barrel.

If a misfire occurs, the operator must hold the tool in the operating position for at least 15 seconds and keep the muzzle against the work surface while disassembling or opening the tool and removing the powder load. See 1915.135(c)(5).

• Holding the tool for 15 seconds helps ensure a delayed ignition does not occur while handling the tool.
• Only after the prescribed wait should the operator carefully remove the charge per manufacturer instructions; if unsure, get a competent person to perform the procedure.

No. Neither tools nor powder charges may be left unattended in places where they would be available to unauthorized persons. See 1915.135(c)(6).

• Store tools and powder charges in locked cabinets or secured toolboxes when not in use.
• Control access to loaded tools and keep track of powder inventories to prevent theft or misuse.

When fastening other material such as a 2×4 to concrete, you must not use fasteners with a shank diameter greater than 7/32 inch; this reduces the risk of damaging the concrete or causing unsafe fastener behavior. See 1915.135(b)(6).

• Use the correct fastener size for the materials to prevent cracking, spalling, or poor anchorage.
• If larger fasteners appear necessary, use alternative fastening methods or consult a competent person.

A "competent person" is someone capable of recognizing and evaluating hazards and specifying necessary protections; for shipyard rules, that person must meet the definition in 29 CFR 1915.4 and can determine required protections and training. See 1915.135(c) and OSHA's letter clarifying competent person responsibilities at https://www.osha.gov/laws-regs/standardinterpretations/2016-04-18.

• The competent person should be knowledgeable about powder actuated tools, hazards, and applicable OSHA rules.
• Employers are responsible for ensuring the competent person is qualified and for implementing their recommendations.

Eye and face protection must meet the shipyard PPE requirements of Subpart I, and selection should follow the criteria in 29 CFR 1915.153; OSHA’s letter on shipyard eye and face protection explains how to interpret those criteria. See 1915.135(b)(9) and the Shipyard eye and face protection Letter of Interpretation.

• Use safety spectacles or face shields that protect against flying particles produced by misfired charges or fragments.
• Do not substitute ordinary sunglasses for work-rated eye protection when hazards include impact; follow the guidance in the interpretation for appropriate devices.

Yes—using a special guard, fixture, or jig can allow you to work closer than the stated unsupported-edge distances, but you must use such engineered controls to safely support and guide the fastener. See 1915.135(b)(6).

• The guard or fixture must securely back or support the material and prevent spalling or loss of anchorage.
• Ensure the fixture is designed for the task and confirmed by a competent person before use.

Keeping the muzzle against the work surface during a misfire and disassembly reduces the risk that a delayed ignition will expel fragments or a projectile at a person. The rule requires holding the tool in position for at least 15 seconds and keeping the muzzle against the work surface while removing the powder load. See 1915.135(c)(5).

• Maintaining contact helps contain any sudden discharge and prevents the tool from recoiling toward an operator or bystander.
• Follow manufacturer procedures when removing a misfired charge and get assistance from a competent person if necessary.

Prevent flying missile hazards by using backing material behind soft substrates, following the minimum edge distances in 1915.135(b)(6), and using guards or fixtures when needed. See 1915.135(b)(5) and 1915.135(b)(6).

• Always back soft materials so fasteners cannot pass through and become projectiles.
• Observe the required clearances from unsupported edges (3 inches for brick/concrete, 1/2 inch for steel, 2 inches for other work when fastening 2×4, etc.).
• Use appropriate shields, muzzle guards, or fixtures to support and guide the fastener.