Chapter 2: Common Injuries and Health and Safety Hazards in Blasting Operations

Learning Objectives

• Identify the three most common blasting and drilling claims.
• Distinguish between exposure and transport claims.
• Describe types of musculoskeletal injuries (MSIs) often presented in drillers and blasters.
• Identify machinery and equipment hazards in blasting and drilling environments.
• Identify risk factors associated with drilling.
• Identify employer requirements to minimize MSIs in the workplace.
• Identify employer requirements to reduce the risk of hearing loss in workers exposed to noise above the noise exposure limit.
• Describe the different noise levels that can occur from equipment or events and through job position.
• List steps in the hierarchy of controls to reduce risks associated with airborne contaminants (e.g., silica dust).
• Describe factors that contribute to impairment in the workplace.
• Explain worker and employer responsibilities related to impairment in the workplace.
• Discuss methods to discourage improper conduct at the worksite.
• Identify potential risks and associated strategies to reduce the risks when blasting or drilling.

Overview

This chapter provides an overview of the most common injuries in blasting operations. It also describes the main blasting-related and other hazards, and discusses how to reduce the risks. Good blast-site management is crucial for eliminating or minimizing safety issues on a site.

Most Common Injuries Among Blasters and Drillers

The following information is based on WorkSafeBC accident statistics for blasters and drillers over a 10-year period.

Top Three Injury Claims

1. Exertion/bodily reaction (40.5%) - Includes strains, sprains, and other musculoskeletal injuries (MSIs). These injuries are typically caused by overexertion (e.g., from moving heavy objects such as rocks and equipment, lifting tools and explosives, and climbing slopes).

2. Falls (23.7%) - Includes sprains and strains, fractures, dislocations, and other injuries. These injuries are caused by falls on snow or ice, falls from trucks or rocks, falls down slopes, and slips and trips on rocks and gravel.

3. Contact with objects (23.0%) - Includes amputations, fractures, eye injuries, burns, concussions, cuts, and other injuries. Some of these injuries are caused by being caught between objects such as pipes, rocks, and equipment. Others are caused by being struck by objects such as drills, tools, and rocks.

Other Claim Types

• Exposures (6.2%) - Includes hearing loss, silicosis (a lung disease caused by inhaling silica dust), and illness caused by exposure to nitroglycerine (NG) products.
• Transport (4.7%) - Includes injuries related to equipment such as excavators and drilling machines, as well as motor vehicle accidents.
• Other (1.8%) - Miscellaneous injuries.

Health and Safety Hazards

Overexertion and Repetitive Movement

Drillers and blasters typically do a lot of bending, lifting, carrying, twisting, and hoisting. These movements can involve overexertion or be repetitive. In some cases, these movements can result in sprains, strains, hernias, and other musculoskeletal injuries (MSIs). MSIs account for roughly one-third of all workplace injury claims accepted by WorkSafeBC.

MSI Risk Factors

The factors that contribute to the risk of MSI are called risk factors. A risk factor is something that may cause or contribute to an injury. Risk factors for MSI include:

• Force
• Duration
• Working position
• Vibration
• Repetition
• Contact stress

There can be two or more risk factors at the same time, increasing the risk of injury.

Employers must identify risk factors that may expose workers to a risk of MSI, assess those risks, and determine and implement appropriate risk controls.

Worker Education

Employers must ensure that workers who may be exposed to a risk of MSI are educated to identify the risks related to the work. Workers should also learn how to recognize early signs and symptoms of MSIs and their potential health effects.

References

Regulation:

• Sections 4.46 to 4.53, Ergonomics (MSI) requirements

Publications:

• Preventing Musculoskeletal Injury (MSI): A Guide for Employers and Joint Committees
• Understanding the Risks of Musculoskeletal Injury (MSI): An Educational Guide for Workers on Sprains, Strains, and Other MSIs

Web (worksafebc.com):

• Sprains & strains
• Lift/lower calculator

Contact with Machinery or Equipment

Unguarded or inadequately safeguarded machinery and equipment are hazards in any workplace that uses powered equipment. Every year, physical contact with machines and powered equipment causes a significant number of injuries, including amputations, and may also result in workplace fatalities. Most of these incidents can be prevented by effective safeguarding procedures and training.

For more information on safeguarding, see the Safeguarding webpage on worksafebc.com.

Vibration

Vibration is a risk factor for a number of conditions, including injuries to the fingers, hands, and back. Two types of vibration hazard can affect workers:

• Hand-arm vibration - Occurs when vibrating objects such as power tools send vibration through the hands and arms.
• Whole-body vibration - Occurs when vibrating surfaces where a worker stands or sits send vibration throughout the body.

In a blasting operation, hand-operated pneumatic rock drills (also known as jackhammers, sinker drills, or pluggers) used for drilling small-diameter drill holes expose workers to high levels of hand-arm vibration or whole-body vibration, depending on how the drill is handled.

Additional Risk Factors

Other risk factors can increase the likelihood of injury from vibration, including:

• Working in cold, damp environments
• Increased grip force
• Using a vibrating tool for long periods

Employers must conduct risk assessments for musculoskeletal injuries (MSIs) in the workplace, and eliminate or minimize the risks. Employers must also educate and train workers about MSI risks in the workplace. For more information, visit the Vibration webpage on worksafebc.com.

Noise

Workers in blasting operations are often exposed to noise that can permanently damage hearing. If workers are exposed to noise that goes over noise exposure limits, employer requirements include the following:

• Develop and implement an effective noise control and hearing conservation program.
• Investigate options for engineered noise control. Implement one or more of those options to reduce noise exposure to or below the exposure limits.
• Post warning signs for noisy areas.
• Provide hearing protection. Make sure it fits each worker and can be worn effectively. Typically, you'll need to provide a variety of hearing protection devices.
• Ensure that workers wear hearing protection as required.
• Make sure workers are provided with an initial hearing test within the first six months and at least once a year after the initial test.

Employers should also make sure workers have their "hearing test card." Workers should carry their cards at work.

The program and hearing protection must meet the requirements of the applicable standard. For more information on what's required in a hearing conservation program, see Part 7 of the Regulation.

Potential Noise Hazards in Blasting Operations

Noise Levels by Job Position

If a worker is or may be exposed to potentially harmful levels of noise, or if information indicates that a worker may be exposed to more than 82 decibels (dBA Lex), the employer must measure the noise exposure.

If workers are exposed to noise that exceeds noise exposure limits, the employer must ensure they have their hearing tested every year to monitor the effectiveness of hearing protection. You can find a list of authorized industrial audiometric (hearing test) facilities at worksafebc.com.

Breathing Hazards

Workers may be at risk of breathing in airborne contaminants such as silica dust. Employers must assess the workplace for breathing hazards and control worker exposure to these hazards.

If elimination isn't practicable, follow the remaining steps in the hierarchy of controls: substitution, engineering controls, administrative controls, and PPE. In many cases, you'll need to use a combination of these controls to keep worker exposures as low as reasonably achievable.

If you can't reduce dangerous air contaminants to safe levels, you must provide your workers with training and appropriate respirators. You must also ensure they use the respirators as they were trained. Respirators must meet and be used in accordance with the requirements of a standard acceptable to WorkSafeBC and the employer's respirator program.

For more information, see sections 8.32 to 8.45 of the Regulation and the WorkSafeBC publication Breathe Safer.

Impairment

Impairment means being unable to perform optimally because of diminished physical or mental capacity. The most common causes of impairment in the workplace are fatigue and substance use.

• Fatigue - The state of feeling tired, weary, or sleepy. It can result from lack of sleep, prolonged mental or physical work, or extended periods of stress or anxiety.
• Substance use - Includes the use of illicit or prescription drugs, alcohol, cannabis, or any other substance that causes impairment.

Risk Controls

Employers can reduce the risk of incidents by following these guidelines:

• Develop a written impairment policy for your workplace. Ensure workers understand the policy and expectations.
• Train supervisors on your policy. They shouldn't be expected to recognize specific effects of substances but should be able to assess acceptable performance and behaviour.
• Limit overtime hours so workers don't work excessively long shifts.

Workers must tell their supervisor or employer if their ability to perform assigned work safely is impaired for any reason. If you are physically or mentally impaired, don't keep working if your impairment could create a risk for you or anyone else.

Employers must not assign impaired workers to activities where impairment may create a risk. Employers must also not knowingly allow workers to remain at work while their ability to work safely is affected by alcohol, a drug, or another substance or condition.

References

Regulation:

• Section 4.19, Physical or mental impairment
• Section 4.20, Impairment by alcohol, drug or other substance

Web (worksafebc.com):

• Substance use & impairment in the workplace
• Fatigue impairment

Horseplay and Similar Conduct

A person must not engage in any improper activity or behaviour at a workplace that might pose a hazard to themselves or anyone else. This includes horseplay, practical jokes, unnecessary running or jumping, and similar conduct. Improper activity or behaviour must be reported and investigated. Employers should put in place written rules prohibiting horseplay and similar conduct, and then enforce those rules.

Flying Material

Flying material (e.g., fly rock) can cause serious injuries, fatalities, and property damage. Fly rock has been known to travel great distances, and the blaster must take into account worst-case scenarios.

At the time of detonation, the blaster of record must be absolutely certain that the area is completely clear and access to the blast site is controlled. A predetermined plan must be prepared for safeguarding all workers and the public prior to the blast. Since many incidents are caused by flying material, the plan must emphasize precautions related to fly rock. Precautions include using sound blast designs, good loading practices, and security procedures.

For more information, see:

• Chapter 10, "Blast design"
• Chapter 13, "Priming and loading explosives"
• Chapter 14, "Controlling the effects of a blast"

Electrical Storms

If there is any sign of thunder or lightning storm activity, all blasting activity must be suspended. In addition, the danger area must be cleared and guarded if explosives are present at the blast site. These actions are required regardless of the types of explosives or initiation systems being used.

Important: Some blasters may have the misconception that electrical storms are not a threat when non-electric initiation systems are used. But a lightning strike can initiate any explosive.

For more information, see "Securing the area surrounding a blast" on page 161 and "Electrical storms" on page 296.