420 questions
When must a scaffold be inspected?
- a.Never
- b.Only once a year
- c.Before each work shift and after any event that could affect its integrity✓
- d.Only when it collapses
Scaffolds must be inspected by a competent person before each work shift and after any occurrence that could affect their structural integrity, such as a storm. Defective scaffolds must be tagged and taken out of service. Regular inspection prevents scaffold collapses and falls.
At what height must most scaffold platforms have fall protection?
- a.50 feet
- b.2 feet
- c.10 feet above a lower level✓
- d.25 feet
Most scaffold platforms require fall protection when they are more than 10 feet above a lower level. This may be provided by guardrails or personal fall arrest systems depending on the scaffold type. The 10-foot scaffold threshold differs from the general 6-foot construction rule.
How must scaffold platforms be planked to prevent workers or tools from falling through?
- a.Planked with 12-inch gaps
- b.Left mostly open
- c.Not planked at all
- d.Fully planked or decked with gaps generally no more than 1 inch around uprights✓
Scaffold platforms must be fully planked or decked, with the space between planks and between the platform and uprights generally not exceeding 1 inch. Larger gaps are only allowed where necessary to fit around uprights. Full planking prevents workers and tools from falling through.
How should a straight or extension ladder be positioned against a wall (the 4-to-1 rule)?
- a.Straight up vertically
- b.4 feet out for every 1 foot of height
- c.1 foot out at the base for every 4 feet of working height✓
- d.At a 90-degree angle
The 4-to-1 rule means the base of the ladder should be placed 1 foot away from the wall for every 4 feet of vertical working height. This angle provides stability and reduces the chance of the ladder sliding out. Setting the ladder too steep or too shallow increases fall risk.
How far above a landing must an extension ladder extend for safe access?
- a.Exactly at the landing edge
- b.It should stop below the landing
- c.10 feet above
- d.At least 3 feet above the landing surface✓
A ladder used to access an upper landing must extend at least 3 feet above the landing surface. This gives the worker something to hold while stepping on and off. If it cannot extend, a grab rail must be provided.
What is the '3-point contact' rule when climbing a ladder?
- a.Keep three limbs in contact with the ladder at all times✓
- b.Touch the ladder three times before climbing
- c.Use only three rungs
- d.Have three workers hold it
Three-point contact means keeping two hands and one foot, or two feet and one hand, on the ladder at all times while climbing. This maintains stability and reduces the chance of falling. Workers should carry tools in a belt or hoist them separately rather than in their hands.
Why should you never stand on the top cap or top step of a stepladder?
- a.It creates instability and a serious fall hazard✓
- b.It voids the warranty
- c.It scratches the ladder
- d.It is perfectly safe to do so
Standing on the top cap or top step of a stepladder raises the center of gravity and makes the ladder unstable, creating a serious fall hazard. Manufacturers label these areas as not for standing. Choosing a taller ladder is the correct solution when more height is needed.
What should be done with a ladder that has a cracked rail or broken rung?
- a.Tag it out of service and remove it from use until repaired or discarded✓
- b.Lend it to another crew
- c.Use it carefully
- d.Tape over the crack and continue
A ladder with structural defects such as a cracked rail or broken rung must be tagged out of service and removed from use. It should be repaired to original condition or destroyed. Using a damaged ladder can lead to sudden failure and a fall.
What is the purpose of a safety net system?
- a.Decoration
- b.To store tools
- c.To catch a falling worker when other fall protection is not feasible✓
- d.To block sunlight
Safety net systems catch a falling worker and are used where guardrails or personal fall arrest are not practical. Nets must be installed as close as practicable under the work surface, never more than 30 feet below. They must be inspected and drop-tested or otherwise certified.
What is a 'controlled access zone' used for in fall protection?
- a.Storing vehicles
- b.Designating an area where certain work may occur with access limited to authorized workers✓
- c.Parking equipment
- d.A break area
A controlled access zone is an area where certain work, such as leading-edge or overhand bricklaying, may take place and where access is limited to authorized workers. It is defined by control lines and used with a safety monitoring system in specific situations. It is a form of alternative fall protection where conventional systems are infeasible.
When is a floor hole or opening a fall hazard that must be protected?
- a.Only outdoors
- b.Never, holes are always safe
- c.When a worker could fall through or step into it, requiring covers or guardrails✓
- d.Only if larger than a door
Holes and openings in floors or roofs through which a worker could fall must be protected with covers, guardrails, or personal fall arrest. Covers must be secured and marked, and be able to support the intended loads. Unprotected openings are a common and preventable fall hazard.
Who is required to train workers on fall hazards and the fall protection systems they will use?
- a.The equipment vendor only
- b.No training is required
- c.Any coworker
- d.A competent person, through a fall protection training program✓
OSHA requires that a competent person train each worker exposed to fall hazards to recognize those hazards and use the fall protection systems correctly. Retraining is required when conditions change or when a worker shows inadequate understanding. Training must be documented with a written certification.
What does the acronym LOTO stand for in workplace safety?
- a.Lift Over Turn Off
- b.Load On Time Out
- c.Lockout/Tagout✓
- d.Line Operator Task Order
LOTO stands for Lockout/Tagout, a procedure to control hazardous energy during servicing and maintenance. It ensures equipment is de-energized and cannot be unexpectedly started. Each authorized worker applies their own lock so the equipment stays safe until work is done.
What is the primary purpose of a lockout/tagout program?
- a.To label finished products
- b.To control hazardous energy so machines cannot start unexpectedly during service✓
- c.To track employee attendance
- d.To lock the tool room at night
The purpose of lockout/tagout is to control hazardous energy sources so that equipment cannot be energized or started while workers service or maintain it. Hazardous energy includes electrical, mechanical, hydraulic, pneumatic, thermal, and stored energy. Unexpected startup or energy release causes many serious injuries.
Under lockout/tagout, who is allowed to remove a lock from equipment?
- a.Any worker who needs the machine
- b.The first person to arrive that day
- c.Generally only the authorized worker who applied that lock✓
- d.A customer
As a rule, only the authorized employee who applied a lock may remove it. This ensures no one is still working on the equipment when it is re-energized. Special documented procedures apply if that worker is unavailable and the lock must be removed.
What does GFCI stand for and what does it protect against?
- a.Ground Fault Circuit Interrupter; it protects against electrical shock✓
- b.Gas Flow Control Instrument; it controls gas
- c.Ground Force Cable Insulator; it insulates cables
- d.General Field Control Inspector; it inspects fields
A GFCI is a Ground Fault Circuit Interrupter that protects workers from electric shock by quickly shutting off power when it detects current leaking to ground. It reacts to very small imbalances in current in a fraction of a second. GFCIs are required for many temporary power and outdoor circuits on construction sites.
On construction sites, what is one acceptable method to protect workers using temporary power from ground faults?
- a.Removing all grounding
- b.Using bare wires
- c.Using GFCI protection on receptacles or an assured equipment grounding conductor program✓
- d.Working in the rain
OSHA requires either GFCI protection on 120-volt temporary receptacles or an assured equipment grounding conductor program on construction sites. GFCIs are the more common and reliable choice. These measures protect against the shock hazards common with temporary wiring and portable tools.
What is the safest approach when working near overhead power lines?
- a.Spray them with water
- b.Touch them to test if they are live
- c.Lean ladders against them
- d.Maintain a safe clearance distance and assume all lines are energized✓
Workers should assume all overhead power lines are energized and maintain the required minimum clearance distance, which increases with voltage. Equipment such as cranes and ladders must be kept well away from lines. Contact with overhead lines is a leading cause of electrocution in construction.
What should you do before using an electrical cord or tool that appears damaged?
- a.Remove it from service and do not use it until repaired or replaced✓
- b.Use it only in dry areas
- c.Use it quickly before it fails
- d.Wrap it in cloth
A damaged cord or tool must be removed from service and not used until it is properly repaired or replaced. Frayed insulation, exposed conductors, or damaged plugs create shock and fire hazards. Inspecting cords and tools before each use is a basic electrical safety practice.
Why should the grounding prong on a three-prong plug never be removed?
- a.It is purely decorative
- b.The grounding prong provides a safe path for fault current, reducing shock risk✓
- c.It makes the plug fit better
- d.It saves electricity
The grounding prong provides a low-resistance path for fault current to flow safely to ground, reducing the risk of shock if a tool develops a fault. Removing or bending it defeats this protection. Tools with a missing ground prong should be taken out of service.
What is the correct action if a coworker is in contact with a live electrical source?
- a.Do nothing and wait
- b.Grab them immediately with bare hands
- c.De-energize the source or use a non-conductive object to separate them, then call for help✓
- d.Pour water on them
You should never touch a person who is in contact with a live electrical source with bare hands, because the current can pass to you. First de-energize the source if possible, or use a non-conductive object to separate the person from the source, then call for emergency help. Attempting a bare-hand rescue can create a second victim.
What is the role of PPE when selected as part of electrical safety?
- a.To make workers look uniform
- b.To protect the worker as a last line of defense when hazards cannot be otherwise removed✓
- c.To increase productivity
- d.To replace training
PPE, such as insulating gloves and arc-rated clothing, protects the worker as the last line of defense when electrical hazards cannot be eliminated or controlled by other means. It must be rated for the voltage and hazard involved. PPE supplements, but never replaces, de-energizing and safe work practices.
What is an arc flash?
- a.A warning label
- b.A type of light bulb
- c.A sudden release of energy from an electrical arc that can cause severe burns✓
- d.A camera flash
An arc flash is a rapid release of energy caused by an electrical arc, producing intense heat, light, and pressure that can cause severe burns and other injuries. Proper arc-rated PPE and safe work distances reduce the danger. De-energizing equipment before work is the best protection.
Which PPE is specifically designed to protect against electrical shock when handling energized conductors?
- a.Cotton work gloves
- b.Rated insulating rubber gloves✓
- c.Leather gloves alone
- d.No gloves needed
Rated insulating rubber gloves, often worn with leather protectors, are designed to protect against electrical shock when working on or near energized conductors. They must be voltage-rated for the task and tested regularly. Ordinary work gloves offer no shock protection.
Why is it dangerous to use electrical equipment in wet or damp conditions?
- a.It makes tools quieter
- b.Water insulates the worker
- c.It has no effect
- d.Water improves conductivity and greatly increases shock risk✓
Water is a conductor and dramatically lowers the body's resistance, increasing the severity of an electric shock. Wet conditions make ground faults far more likely to injure a worker. GFCI protection and keeping connections dry are essential in these environments.
What is the first step in a typical lockout/tagout procedure?
- a.Prepare for shutdown by identifying energy sources and notifying affected employees✓
- b.Start the machine
- c.Leave the area
- d.Remove all guards
The first step of lockout/tagout is preparation: identifying all energy sources and notifying affected employees of the planned shutdown. The equipment is then shut down, isolated, locked and tagged, and any stored energy released. Finally, the isolation is verified before work begins.
After applying locks and tags, what critical step verifies the equipment is safe?
- a.Skip verification to save time
- b.Attempt to start the equipment to confirm it will not operate (verify zero energy)✓
- c.Paint the machine
- d.Assume it is off
After isolating and locking out energy, workers must verify a zero-energy state, often by attempting to start the equipment to confirm it will not operate. Test instruments are used to confirm electrical circuits are de-energized. Skipping verification is a common and dangerous mistake.
What does 'stored energy' refer to in lockout/tagout?
- a.Solar panels
- b.Backup generators
- c.Residual energy such as in capacitors, springs, hydraulics, or elevated parts that must be released or restrained✓
- d.Energy in batteries only
Stored energy is residual or potential energy that remains after the main source is disconnected, such as in capacitors, compressed springs, pressurized hydraulics, or raised machine parts. This energy must be released, blocked, or restrained before servicing. Overlooking stored energy can cause unexpected and dangerous movement.
What should unqualified workers do around exposed energized electrical parts?
- a.Stand as close as possible
- b.Stay outside the limited approach boundary unless qualified and protected✓
- c.There is no concern
- d.Touch them to test
Unqualified workers must stay outside the established approach boundaries around exposed energized parts. Only qualified persons with proper training and PPE may approach closer under controlled conditions. Maintaining distance prevents accidental contact and arc-flash exposure.
Why must extension cords used in construction be rated for hard or extra-hard usage?
- a.To conduct more electricity
- b.To withstand the rough conditions of a job site without insulation damage✓
- c.To look professional
- d.To reduce cost
Construction extension cords must be rated for hard or extra-hard usage so their insulation can withstand abrasion, moisture, and rough handling on a job site. Cords rated only for household use damage easily and create shock and fire hazards. The rating is marked on the cord jacket.
What is the danger of overloading an electrical circuit or extension cord?
- a.Faster tool operation
- b.There is no danger
- c.Overheating that can cause fires and equipment damage✓
- d.It saves money
Overloading a circuit or cord draws more current than it is rated for, causing it to overheat and potentially start a fire or damage equipment. Cords should be sized for the load and length of the run. Daisy-chaining cords and power strips increases this risk.
Which of the following best describes a 'qualified person' for electrical work?
- a.Anyone wearing gloves
- b.A person trained and knowledgeable in electrical equipment operation and the hazards involved✓
- c.A new apprentice on day one
- d.A visitor to the site
A qualified person is trained and knowledgeable in the construction and operation of electrical equipment and installations and in recognizing and avoiding the associated hazards. Only qualified persons may perform certain energized electrical tasks. Proper training and demonstrated skill define this designation.
What does the Hazard Communication Standard (HazCom) require employers to provide about chemicals?
- a.Only a phone number
- b.A discount on the chemicals
- c.Nothing
- d.Labels, safety data sheets, and worker training about chemical hazards✓
The Hazard Communication Standard requires employers to inform and train workers about the hazardous chemicals they may be exposed to. This includes proper labeling, accessible Safety Data Sheets, and a written hazard communication program. Workers must be trained on how to protect themselves.
What is a Safety Data Sheet (SDS)?
- a.A vacation request
- b.A payroll form
- c.A building permit
- d.A document providing detailed hazard, handling, and emergency information about a chemical✓
A Safety Data Sheet provides detailed information about a hazardous chemical, including its hazards, safe handling, storage, first aid, and emergency measures. SDSs follow a standardized 16-section format. They must be readily accessible to workers on every shift.
How many sections does a standardized Safety Data Sheet contain under the Globally Harmonized System?
- a.3 sections
- b.5 sections
- c.16 sections✓
- d.50 sections
A standardized Safety Data Sheet contains 16 sections under the Globally Harmonized System of Classification and Labeling. The sections cover identification, hazards, composition, first aid, firefighting, handling, exposure controls, and more. This uniform format makes information easier to find.
What health hazard is associated with breathing respirable crystalline silica dust?
- a.Temporary sneezing only
- b.Improved lung function
- c.Better eyesight
- d.Silicosis, an incurable and sometimes fatal lung disease✓
Inhaling respirable crystalline silica dust can cause silicosis, an incurable and potentially fatal lung disease, as well as lung cancer and other illnesses. Silica is released when cutting, grinding, or drilling concrete, brick, and stone. Controlling dust at the source is critical to prevention.
Which is an effective engineering control to reduce silica exposure when cutting concrete?
- a.Holding your breath
- b.Cutting in an enclosed room with no ventilation
- c.Working faster
- d.Using water (wet methods) or local exhaust ventilation to suppress dust✓
Wet cutting methods and tools with local exhaust ventilation and vacuum dust collection are effective engineering controls that keep silica dust out of the air. These controls are preferred over relying on respirators alone. Reducing dust at the source protects everyone nearby.
When engineering controls cannot reduce silica below safe levels, what additional protection is used?
- a.A cloth bandana
- b.Sunglasses
- c.A properly selected and fit-tested respirator✓
- d.No protection
When engineering and work-practice controls cannot reduce silica exposure to acceptable levels, a properly selected and fit-tested respirator must be used. Respirators require a program including medical evaluation, fit testing, and training. They supplement, not replace, dust controls.
What is the purpose of a respirator fit test?
- a.To test breathing speed for fun
- b.To check the color
- c.To measure the worker's height
- d.To ensure a tight-fitting respirator seals properly to the wearer's face✓
A fit test verifies that a tight-fitting respirator forms an effective seal against the wearer's face so contaminants cannot leak in. It must be done before first use and periodically thereafter. Facial hair or an improper size can break the seal and defeat protection.
What is the best way to prevent back injuries when manually handling materials?
- a.Lift with a rounded back
- b.Use proper lifting technique, mechanical aids, and team lifting for heavy loads✓
- c.Lift the heaviest object alone quickly
- d.Twist while carrying
Back injuries are prevented by using proper lifting technique, keeping the load close, lifting with the legs, and avoiding twisting. Mechanical aids like carts and hoists and team lifting should be used for heavy or awkward loads. Planning the lift and clearing the path also reduce risk.
What is a symptom of heat exhaustion that workers should recognize?
- a.No symptoms at all
- b.Improved concentration
- c.Heavy sweating, weakness, dizziness, and nausea✓
- d.Feeling energetic
Heat exhaustion symptoms include heavy sweating, weakness, dizziness, headache, nausea, and clammy skin. Affected workers should move to a cool area, rest, and drink water. If symptoms worsen or confusion appears, it may signal heat stroke, a medical emergency.
What are the key elements of preventing heat illness on the job?
- a.Skipping breaks
- b.Wearing heavy dark clothing
- c.Water, rest, and shade✓
- d.Working nonstop in the sun
The key elements of heat illness prevention are water, rest, and shade, along with acclimatization for new or returning workers. Workers should drink water regularly, take breaks in shaded or cool areas, and watch for symptoms in themselves and others. Gradually building tolerance to heat is especially important.
What does an occupational noise exposure program aim to prevent?
- a.Faster work
- b.Noise-induced hearing loss through monitoring, controls, and hearing protection✓
- c.Better hearing
- d.Louder equipment
A hearing conservation program aims to prevent permanent noise-induced hearing loss. It includes noise monitoring, engineering and administrative controls, hearing protection, audiometric testing, and training. Hearing loss from noise is permanent but entirely preventable.
Which pictogram on a chemical label under GHS indicates a serious health hazard such as carcinogenicity?
- a.A smiley face
- b.A dollar sign
- c.A clock
- d.A human silhouette with a star-burst on the chest (health hazard symbol)✓
The GHS health hazard pictogram shows a human silhouette with a star-burst on the chest and warns of serious health effects such as carcinogenicity, respiratory sensitization, or organ toxicity. Recognizing GHS pictograms helps workers quickly understand chemical dangers. Each pictogram has a red diamond border.
What should a written hazard communication program include?
- a.A chemical inventory, labeling system, SDS access, and employee training plan✓
- b.Only the company logo
- c.Only a list of employees
- d.A lunch menu
A written hazard communication program must describe how the employer will maintain a chemical inventory, ensure containers are labeled, keep Safety Data Sheets accessible, and train employees. It ties together all elements of the HazCom standard. The program must be available to workers on request.
Why is it important to keep containers of hazardous chemicals properly labeled?
- a.To make them heavier
- b.To increase the price
- c.For decoration
- d.So workers can identify the contents and hazards and take proper precautions✓
Proper labeling ensures workers can quickly identify a chemical and its hazards so they can handle, store, and dispose of it safely. Labels must include the product identifier, signal word, hazard statements, and pictograms. Unlabeled or mislabeled containers are a serious and common violation.
What is the main hazard of working in a poorly ventilated area with solvents or fumes?
- a.Stronger materials
- b.Cooler temperatures
- c.Inhalation of toxic vapors that can cause illness or asphyxiation✓
- d.Better air quality
Poor ventilation allows toxic vapors, fumes, or gases to accumulate, which can cause illness, unconsciousness, or asphyxiation. Adequate ventilation, respiratory protection, and atmospheric monitoring reduce the risk. Solvent vapors may also create fire and explosion hazards.
What is 'acclimatization' in the context of working in hot environments?
- a.Gradually building the body's tolerance to heat over several days✓
- b.Wearing more layers
- c.Instantly working full shifts in heat
- d.Avoiding all water
Acclimatization is the process of gradually increasing a worker's exposure to heat over about one to two weeks so the body adapts. New workers and those returning from time off are at highest risk before they acclimatize. Many heat fatalities occur in a worker's first few days on the job.
How should hazardous materials generally be stored to reduce risk?
- a.In open buckets
- b.According to compatibility, with incompatible chemicals separated and containers labeled✓
- c.Mixed together to save space
- d.Near ignition sources
Hazardous materials should be stored according to their compatibility, keeping incompatible chemicals such as acids and bases separated to prevent dangerous reactions. Containers must be closed, labeled, and kept away from ignition sources where flammable. Safety Data Sheets provide storage guidance for each material.
What is the purpose of medical surveillance for workers exposed to certain health hazards?
- a.To replace ventilation
- b.To increase work hours
- c.To detect early signs of illness so exposure can be reduced before serious harm occurs✓
- d.To reduce wages
Medical surveillance monitors workers exposed to hazards such as silica, lead, or asbestos to detect early signs of illness. Early detection allows intervention before disease becomes serious or irreversible. It also helps evaluate whether workplace controls are effective.