Site clearing requirements

Yes — employers must both protect workers from poisonous or irritating plants and teach them what first aid to use if exposure happens. This means employers should identify plant hazards, provide controls (such as gloves, protective clothing, or changing work methods), and give workers clear, practical first-aid instruction for exposures (for example, washing affected skin, removing contaminated clothing, or seeking medical help).

• Primary requirement: 1926.604(a)(1).
• How to decide what protection and training are needed: perform a hazard assessment to select PPE and training appropriate to the risks, following OSHA guidance on employer hazard assessments (see the PPE hazard assessment interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

Yes — all equipment used in site clearing must be equipped with rollover guards that meet the requirements of this subpart. That includes tractors, brush cutters, and other mechanized clearing equipment when they are used for site clearing operations.

• See the requirement in 1926.604(a)(2).
• Employers should also conduct a hazard assessment to determine any additional protective measures or PPE needed for workers operating or working near such equipment (see the PPE hazard assessment interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

The overhead canopy must be made of at least 1/8-inch steel plate or 1/4-inch woven wire mesh with openings no greater than 1 inch, or a material of equivalent protective strength. In short: use 1/8" steel plate or 1/4" woven wire mesh (max 1" openings) unless you can show another material gives the same protection.

• See the exact material and size requirements in 1926.604(a)(2)(i).

The rear opening of the canopy must be covered with not less than 1/4-inch woven wire mesh with openings no greater than 1 inch. In other words, the back of the canopy cannot be left open; it must have 1/4" woven wire mesh (max 1" openings).

• See the rear-canopy requirement in 1926.604(a)(2)(ii).

"Or equivalent" means you may use another material or construction only if it provides the same level of overhead protection against flying or falling objects as the specified 1/8-inch steel plate or 1/4-inch woven wire mesh with 1-inch maximum openings. You should be able to demonstrate equivalence by documentation or testing showing equal protective strength.

• The base requirement is in 1926.604(a)(2)(i).
• Use your employer hazard assessment to justify any alternative material; OSHA guidance on PPE and hazard assessments explains employers’ responsibility to evaluate and document protective choices (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

No — 1926.604(a)(1) requires that employees be suitably instructed in the first aid treatment available, but it does not set a specific written-first-aid format or mandate CPR retraining intervals. Employers must provide appropriate first-aid instruction based on the hazards present, and some other OSHA standards do require specific training where applicable.

• See the site-clearing instruction requirement in 1926.604(a)(1).
• OSHA guidance explains that while OSHA recommends regular CPR retraining (for example, annually), OSHA does not mandate a retraining interval for CPR in general industry construction except where a specific standard requires it; see the CPR/first aid interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2023-02-23 for more context.

Suitable first-aid instruction should directly address the likely injuries from plant and clearing hazards — for example, recognizing and treating contact with poison ivy or other toxic plants, basic wound care for cuts and punctures, decontamination (washing skin/clothing), and how to get emergency medical help. Training should be clear, practical, and available before workers begin hazardous tasks.

• Requirement reference: 1926.604(a)(1).
• Employers should base the content on a workplace hazard assessment and follow OSHA guidance on PPE and hazard assessment to determine what first-aid topics and PPE are needed (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28 and the CPR LOI at https://www.osha.gov/laws-regs/standardinterpretations/2023-02-23).

The standard specifically requires rider-operated equipment to have an overhead and rear canopy guard constructed as described. Walk-behind or non-rider handheld equipment is not subject to the rider-operated canopy specifications, but employers must still protect workers from hazards and provide appropriate guards and PPE as determined by a hazard assessment.

• Rider-equipment requirement: 1926.604(a)(2).
• For any equipment, employers should perform a hazard assessment and supply appropriate guards or PPE per OSHA guidance (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

Yes — the overhead canopy (if mesh is used) must be 1/4-inch woven wire mesh with openings no greater than 1 inch, and the rear opening must be covered with at least 1/4-inch woven wire mesh with openings no greater than 1 inch. Both places limit openings to no larger than 1 inch.

• Overhead mesh spec: 1926.604(a)(2)(i).
• Rear mesh spec: 1926.604(a)(2)(ii).

The employer is responsible for deciding and providing the first-aid supplies and PPE that are readily available to protect workers; decisions should be based on a hazard assessment of site-clearing tasks. Employers must determine which hazards are present and then supply appropriate first-aid measures and PPE.

• Site-clearing duty to instruct and protect: 1926.604(a)(1).
• OSHA stresses that employers must perform hazard assessments to select PPE and protections — see the PPE hazard assessment interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28 for guidance on employer responsibilities.

The regulation requires that rider-operated equipment be equipped with the specified overhead and rear canopy guards, but it does not mandate that the guards be factory-installed. Field-installed guards are acceptable provided they meet the material and size requirements (e.g., 1/8" steel plate or 1/4" woven wire mesh with openings no greater than 1"), or are shown to be equivalent in protective value.

• Material and performance requirements are set out in 1926.604(a)(2)(i) and 1926.604(a)(2)(ii).
• Any alternative or field modification should be documented and justified via your hazard assessment (see OSHA's PPE hazard assessment interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

1926.604 requires protection from plant hazards and specifies machine guards, but it does not itself detail respiratory protection. If site clearing creates airborne hazards (dust, mold, asbestos), the employer must assess those hazards and provide appropriate respiratory protection and controls under the applicable OSHA standards — for example, follow the employer PPE and hazard assessment obligations and the specific respirator or asbestos standards as applicable.

• Site-clearing requirements: 1926.604(a).
• Employers must perform hazard assessments and select PPE (including respirators) as required by OSHA; see the PPE hazard assessment interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28. If asbestos is a potential hazard, consult OSHA's asbestos-in-construction requirements (see the asbestos interpretation at https://www.osha.gov/laws-regs/standardinterpretations/2024-11-14 for guidance on which asbestos standard applies).

No — 1926.604(a)(2) specifies required guards and materials but does not set specific maintenance or inspection intervals. However, employers are responsible for ensuring equipment remains in safe, working condition; regular inspections and maintenance are a best practice and often required by other applicable equipment or employer-responsibility standards.

• Guard requirement: 1926.604(a)(2).
• For how to determine maintenance and PPE program needs, perform a workplace hazard assessment and follow OSHA guidance on PPE and employer responsibilities (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

Yes — the wording covers employees engaged in site clearing generally, regardless of job size or duration; workers must be protected from irritant and toxic plants and be instructed in available first-aid treatment, and equipment used must have the required guards when applicable.

• See the general requirements in 1926.604(a).
• Employers should perform a task-specific hazard assessment even for short jobs to determine needed PPE, training, and equipment guards (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

The employer employing the workers performing the site-clearing tasks is responsible for training them about toxic plants and first-aid available. If multiple employers are on the same site, each employer must ensure their employees receive required protections and training; coordination between contractors is essential to cover shared hazards.

• Training and protection duty: 1926.604(a)(1).
• Employers should base training on a hazard assessment and coordinate with other employers on site to ensure all workers are protected (see PPE hazard assessment guidance at https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).

If a rider-operated machine already has a solid overhead surface (for example, a factory-installed steel roof of at least the strength equivalent to 1/8-inch steel plate), that satisfies the overhead covering requirement. The standard's goal is adequate overhead protection, so a solid roof meeting or exceeding the protective level is acceptable.

• Overhead protection specification: 1926.604(a)(2)(i).
• If using an alternative design, be prepared to show it provides equivalent protection — employers should document hazard assessments and decisions about protective features (see https://www.osha.gov/laws-regs/standardinterpretations/2024-03-28).