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Hazard Controls

Worker in PPE

Recognize-Evaluate-Control (REC)

The REC approach to managing hazards is designed to reduce the risk of illness, injury, and death in the workplace.

  1. Survey the work area, equipment, and tasks performed. Look for  existing or potential hazards. A basic checklist is available for use, a consultant may be available in your area, training may be available, or you may rely on the knowledge and experience of farm managers, supervisors, and  workers. Examples of hazards on farms includes, tractor turnover, entanglement from farm implements (i.e. rotating shafts, PTOs, gears, belts, etc.), large animal handling, lifting heavy items, climbing or working at heights, slippery walking surfaces, various machinery and equipment such as chain saws or ATVs, operating heavy equipment such as dump trucks or back hoes where there may be an obstructed view to the rear, entering confined spaces such as silos or manure pits, heat stress or hypothermia, adverse weather conditions, etc. 
  2. Each hazard should be reviewed to determine the risk involved. Risk refers to the severity of injury (should one occur) and the probability of it happening. A routine (i.e. daily) task that could result in  a serious injury or death should be considered "high" risk, where intervention should occur. For example, climbing a ladder 10-15 feet tall where there is no means of fall protection and rungs may be slippery. A fall from as little as 4 feet could result in an injury where days of work are missed. Working around PTOs when cutting hay, for example, may only occur during summer months, but the severity of injury could be quite high. Other tasks may only result in minor injuries, and would be considered low risk. Intervention for low risk situations may not be necessary.
  3. Consider solutions or controls for the high and medium risk situations.  Can the hazard be eliminated? If not, are there engineering controls that can be incorporated to eliminate access to the hazard? Examples would include guarding, ventilation, automation of physically intense tasks, or isolation of the hazard.  Can exposure to the hazard be reduced or controlled to such a manner that  injury is greatly reduced? Examples include training on the hazard, procedures that reduce the chance of exposure to a hazard or injury, or working early in the morning or at night to reduce heat stress, etc.  As a last resort, the use of personal protective equipment, such as safety glasses, gloves, respiratory protection, steel-toed work boots, should be considered.

All serious hazards should be addressed immediately. Avoid selecting controls that may directly or indirectly introduce new hazards. Examples include exhausting contaminated air into occupied work spaces, or using hearing protection that makes it difficult to hear backup alarms.

Managing the risks associated with your work is a shared responsibility. Involve workers who are using the machinery/equipment or performing the task to help identify hazards, and offer solutions.  Regulations, laws, training, and workplace policies are only a small part of what makes a workplace safe. We encourage each of you to be innovative as you work with each other, your supervisors, and senior managers to create a safe and healthful workplace.  Ask questions, talk openly, and share your ideas and solutions with each other.

Hierarchy of Controls

When evaluating any given hazard, always start with the possibility of eliminating the hazard.  Is there a substitution available? Engineering controls isolate or remove the hazard and eliminate or greatly reduce the possibility of exposure. Administrative controls help manage behaviors and procedures that reduce the likelihood of an injury or exposure to a hazard. The purpose of personal protective equipment is to minimize the extent (severity) of the injury.

Hierarchy of Controls graphic

Elimination of a hazard is completely removing the hazard so that it does not pose an issue. Examples include:

  • Getting rid of old machinery or equipment which is not properly guarded, or cannot be guarded for some reason
  • Relocating elevated work to ground level so that exposure to a fall is removed
  • Backfilling a pit that is no longer used, or filling a groundhog hole
  • Removing snow, ice, or mud from walking surfaces
  • Ask yourself if the task or process even necessary?


damaged drill

Substitution involves replacing the hazard with a non-hazardous option. Examples include:

  • Using water instead of a hazardous chemical for cleaning
  • Painting with a brush instead of aerosolized spraying
  • Using a less hazardous chemical for a hazardous one
  • Automated mixing instead of manual methods
  • Bolting two pieces of metal together rather than welding it (which creates a fire hazard, burn hazards, and potential damage to the eyes) 
box of spray cans

Engineering controls isolate people from the hazard so that injury or illness is not possible. Examples include:

  • Machine guarding
  • Guardrails or proper work platforms
  • Hole covers
  • Electrical covers on junction boxes and in panels
  • Ventilation
  • Dust collection systems/features
PTO guarding

Administrative controls do not remove the hazard, but rather reduce the likelihood of serious injury or exposure by changing the way people work around the hazard. It may not reduce the risk to an acceptable level, and additional means such as personal protective equipment may be necessary. Examples include:

  • Reading and following manufacturer's instructions on machinery and equipment
  • Use of warning signs or markings
  • Safe work practices or procedures (ex. ladder safety, animal handling)
  • Back up alarms on heavy equipment
  • Safe distances from the hazard
  • De-energize and secure any hazardous energy source before performing servicing/maintenance activities or entering confined spaces
  • Check the air before entering confined spaces
  • Frequent breaks to rest, hydrate, cool off or get warm 
Person walking a horse

Personal protective equipment (PPE) protects the worker from the hazard and/or minimizes the severity of injury or exposure. It is worn by the worker, and the degree of protectiveness can vary due to factors such as proper use, cleaning, maintenance, or design limitations. Examples include:

  • Protective headwear
  • Safety glasses or goggles
  • Face shields or welding helmets
  • Respirators and dust masks
  • Flame-retardant jackets or sleeves
  • Various types of gloves (i.e. hazard-specific)
  • Chaps and shin guards
  • High-visibiltity shirts, vests, or jackets
  • Slip-resistant footwear or steel-toed boots
  • Use of seatbelts
  • Sunscreen and/or brimmed hats
person in muck boots