Exam 2 Flashcards
What are the routes of entry for health hazards?
Inhalation: airborne contaminants
Absorption: penetration through the skin
Ingestion: eating or drinking
Injection: breaking of the skin for contaminated to enter
OSHA Hierarchy of Controls:
1) Engineering Controls
2) Work Practice Controls
3) Administrative Controls
4) PPE
What are the types of exposure?
Acute and Chronic
What is acute exposure?
Short term period between exposure and onset of symptoms
What is chronic exposure?
long term period between exposure to an agent and the onset of symptoms
What does OSHA stand for?
Occupational Safety and Health Administration
What does NIOSH stand for?
National Institute of Occupational Safety and Health
What does ACGIH stand for?
American Conference of Governmental Industrial Hygienists
What does OSHA cover for air contaminants?
PEL,STEL,Ceiling
What does NIOSH cover for air contaminants?
TWA,STEL,Ceiling
What does ACGIH cover for air contaminants?
TWA,STEL,Ceiling
What is TWA?
takes into account variable exposure through a full shift, 8 hour work day
What is STEL?
limit of exposure during a short period, 15 minutes
What is ceiling?
absolute maximum level of exposure not to be exceeded
What air contaminants are legally enforceable?
- OSHA PEL
- OSHA AL (action level)
- OSHA EL (exposure limit)
What is SEP?
Special Emphasis Program–Silica
What is Silica Special Emphasis Program (SEP)?
Collaboration of OSHA Compliance and Consultation Programs
What is silica?
SiO2
Why Target Crystalline Silica Exposure?
- Widespread occurrence and use
- Number of related deaths
- Number of exposed workers
- Health effects
What is SiO2?
basic component of sand, quartz & granite
What is Quartz?
2nd most common mineral in the earth’s crust
Airborne silica is produced by:
- sandblasting
- rock drilling
- foundry work
- stone cutting
- drilling
- quarrying
- tunneling jack hammering
- concrete manufacturing
- demolition
- asphalt pavement manufacturing
What is Construction Targeting?
- jack hammering
- rock drilling
- abrasive blasting
- concrete mixing
- brick and concrete block or slab cutting
Permissible Exposure Limit(PEL) for Silica?
10 mg/m3
% Quartz +2 = ? mg/m3
(PEL for respirable dust containing a % silica)
What is part of the Silicosis Prevention Program?
Medical surveillance program
- baseline examination
- -medical and occupational history
- -prior to exposure
When must medical examinations for silica exposure take place?
- every 5 years if < 20 years of exposure
- every 2 years if > 20 years of exposure
What is part of a silica exposure examination?
- baseline chest x-ray
- pulmonary function tests (PFT)
- x-ray upon termination of employment
What other factors are part of the Silicosis Prevention Program?
- Personal air monitoring program
- Training and information on crystalline silica
- Availability of air and medical surveillance data to workers
- Respiratory protection program
- Hygiene facilities and clothing change areas
- Recordkeeping
- Personal exposures below the PEL OR facility has an abatement program that provides interim worker protection
- Housekeeping program
- Regulated areas
intense crystalline silica exposure
Acute
more intense silica exposure over 5 to 15 years
Accelerated
20 to 45 years prolonged exposure to crystalline silica
Chronic
What are some common construction health hazards?
- Abrasive blasting
- Paint removal
- Renovation & demolition
- Road repair
What are some Exposure Controls through substitution?
- Coal slag (black beauty)
- Steel grit
- Aluminum oxide
- Wild stuff (frozen CO2, walnut shells, baking soda
What are some Exposure Controls through wet methods?
- Water suppression of dust
- Very effective method
- May be less efficient
- Requires supply of water and clean up
- Power tools with HEPA exhaust
What is cadmium (29 CFR 1926.1127)?
- Blue-white metal
- Grayish-white powder
- Found in lead, copper, and zinc sulfide ores
- Compounds
- -highly colored from brown to yellow and red
What are the uses of cadmium?
- electrode component in alkaline batteries
- stabilizer in plastics
- paints
What are short term cadmium exposure symptoms?
- irritation of upper respiratory tract
- constriction of the throat
- metallic taste
- cough
- flu-like symptoms
What are long term cadmium exposure symptoms?
- kidney damage
- lung cancer
- prostate cancer
All occupational exposure to cadmium compounds:
- in all construction work
- -construction
- -alteration
- -repair
What are covered activities?
- Wrecking
- Demolition
- Salvage
- Use of cadmium containing paints
- Cutting, brazing, burning, grinding or welding
- Electrical grounding w/cadmium
- Installation of cadmium products
- Emergencies
- Transportation, disposal, and storage
What is Action level (AL) for cadmium?
2.5 ug/m3
What does a Competent person do(29 CFR 1926.32)?
- determines presents of cadmium
- regulated areas
- access
- PPE
- training
Permissible Exposure Limit (PEL) for cadmium?
PEL = 5 ug/m3
Exposure Monitoring for cadmium?
- Prior to performance
- Exposure at or above the AL
- -relevant plans
- -reports
- -MSDSs
- -other records
- Frequency
- Additional monitoring
What are Prohibited Activities when working with cadmium?
-Eating
-Drinking
-Smoking
-Chew tobacco
-Apply cosmetics
OR
carry such products into regulated areas
FINISH HEALTH HAZARDS AFTER KAHOOT
FINISH HEALTH HAZARDS AFTER KAHOOT
At what distances is fall protection required?
4 feet or more for General Industry
5 feet or more for Maritime
6 feet or more for Construction
At unsafe distances what must be in use?
Must be protected by Covers, Guardrail, Safety Net, Personal Fall Protections Systems, Travel Restraint System or refers to another standard
(If not feasible, a fall protection plan that meets 1926.502(k) could be implemented under certain conditions)
What sections are in 1926 Subpart M Fall Protection?
.500 Scope, Application and Definitions
.501 Duty to have fall protection
.502 Fall protection system criteria and practices
.503 Training requirements
What is surface strength?
Walking/working surfaces must be strong enough to handle the maximum intended load
What is an unprotected side or edge fall hazard?
Each employee on a walking/working surface (horizontal and vertical surface) with an unprotected side or edge
Each employee who is constructing a _____ ______ must be protected
leading edge
Each employee in the hoist area shall be
protected from falling
Holes larger than ___ must be protected by covers, guardrails, nets or other means
2 inches
Employees on formwork or reinforcing steel must be protected when
6 feet or more above the surface below them
Protection is required on ramps, runways, and other walkways where
a fall could occur
Excavations over _______ that are not readily seen must be protected
6 feet deep
Wells, pits, shafts, or similar excavations ______
6 ft. or more must have protection
For repair, service and assembly pits,
Less than 10 feet deep do not require fall protection if the employer:
- Limits access within 6 feet to authorized employees trained
- Floor Markings or Warning Line at 6 feet from edge of pit
- “Caution - Open Pit” signs
Each employee working above dangerous equipment must be
protected from falling into or onto dangerous equipment
What is overhead bricklaying?
Laying bricks on the opposite side of the wall from the mason, requiring the mason to lean over the wall to complete the work
the hoisting, storage, application, and removal of roofing materials and equipment, including related insulation, sheet metal, and vapor barrier work, but not including the construction of the roof deck
Roofing work
Low-sloped means a roof having a slope less than or equal to
4 in 12
Steep roofs means a roof having a slope greater than
4 in 12
Workers on steep roofs need
guardrail systems with toeboards, safety net systems, or personal fall arrest systems
What is Pre-Cast Concrete Erection?
Concrete components are brought to the site and put together (tilted up) to create a structure
What is Residential Construction?
Applies for homes built with traditional wood frame construction and methods
If employer can prove “infeasibility” in Residential Construction than
A “Fall Protection Plan” can be used
Window sills and other openings _____ above foot level must have protection
less than 39”
Whenever overhead hazards exist, OSHA requires:
- Head protection
- Toeboards, screens, or guardrail systems
OR - Canopies and barricades
Any walking/working surface __ feet (General Industry)/___ feet (Construction) or more above the lower level needs protection
4
6
The employer must provide a training program for each employee that:
- Teaches each employee to recognize fall hazards;
and
- Teaches each employee your procedures to minimize fall hazards
What are the hierarchy of controls?
- Elimination
- Substitution
- Engineering Controls
- Administrative Controls
- PPE
What is elimination?
Physically remove the hazard
What is substitution?
Replace the hazard
What are engineering controls?
Isolate people from the hazard
What are administrative controls?
Change the way people work
What is PPE?
Protect the worker with personal protective equipment
What is the fall protection hierarchy of controls?
1) Eliminate the Fall Hazard
2) Passive Fall Protection
3) Active Fall Protection
4) Fall Arrest
5) Administrative Controls
What does eliminating the Fall Hazard consist of?
- Eliminate work at height
- Design changes to allow work to take place at ground level
What is passive fall protection?
- Physical barriers such as guardrails or parapets
- Safety net systems
What is active fall protection?
Travel restraint keeps the worker from reaching the fall zone
What is a fall arrest system?
- Personal Fall Arrest System (PFAS)
- Positioning Device Systems (PDS)
What are administration controls?
Controlled Access Zones (CAZ)
Safety Monitoring Systems
Warning Line Systems
Fall Protection Plan
What are Elimination: Cocoon Systems?
- Wrap the structure with material to create temporary walls
- Fall and falling object hazards are eliminated
What are Elimination: Move Work to Ground Level?
Assembling Roof Assemblies on the Ground
What are guardian systems?
Wood, cables, pipe, or steel
Surfaced to prevent injury
Must fully extend around the perimeter
Top rails for guardrails are must be ____
39 to 45 inches high.
Midrails, screens, or mesh are required
Guardrails should be _____ ______ and No opening can be wider than __ inches
fully closed
19
Top rails for guardrails must handle a ___ _____force to the outward or downward direction
200 pound
Guardrail mid rails must handle force of
150 lbs
Cables must be at least ____ diameter & flagged every ____ with high-visibility material
¼ inch
6 feet
When load is applied, the cable guardrail shall not deflect to a height less than
39 inches
Install nets close to the working surface, but no more than
30 feet below
What is Net Maintenance?
Inspect regularly for net damage
Inspect after any incident that could harm the net
Remove damaged nets from service
Drop testing or certification is required for
Net Testing
Hole Covers requirements?
Use sturdy material to cover the hole
Secure the cover
Mark with “Hole” or “Cover”
What are some Protective Methods Allowed in Specific Situations?
Controlled access zones (CAZ)
Warning lines
Safety monitors
Fall protection plans
How is infeasibility handled?
Impossible to do the work with conventional fall protection (guardrails, safety nets or PFAS)
Standard presumes feasibility
Employer has the burden of proving infeasibility
How can Controlled Access Zones (CAZ) be used?
- May be used as part of a fall protection plan for
- -Leading edge work
- -Precast operations
- -Residential construction
- May be used as part of a fall protection alternative withouta fall protection plan for
- -Overhand bricklaying operations
What is necessary for Leading Edge Work?
Conventional fall protection
If infeasible or greater hazard, use a fall protection plan
Controlled access zone is part of a fall protection plan
Safety monitor is part of thefall protection
Control lines must be between
6 and 25 feet from edge
- Except when erecting precast (will discuss shortly)
- Except when used in overhand brick laying (will discuss shortly)
Control line must:
Have a 200 pound breaking strength
Be between 39 and 45 inches high
Be flagged or marked at least every six feet
As part of a fall protection plan, CAZ required in areas where conventional fall protection is infeasible:
- Setting and bracing roof trusses and rafters
- Installing floor sheathing and joists
- Roof sheathing operations
- Erecting exterior walls
For Low Slope Roofing OSHA allows:
- Conventional fall protection
- Warning lines and guardrails
- Warning lines and safety nets
- Warning lines and personal fall arrest system
- Warning lines and safety monitor
- On roofs 50-feet wide or less, a safety monitor alone
Warning Line Systems should have:
Ropes, wires, or chains
34” to 39” high
Flagged every 6’
16-pound tipover strength
Roofing Warning Line Requirements state:
- Must extend around all sides of the work area 6’ or more from roof edge
- Workers outside warning lines protected with conventional fall protection or safety monitor
Parapets must be at least __ high orfall protection must be provided
39”
Safety Monitoring Systems require:
Competent person
Be on the same surface close enough to see and communicate
Have no other responsibilities
Fall Protection Plans ______
Only allowed for leading edge work, precast concrete work, or residential construction
Demonstrate that it is infeasible or creates a greater hazard to use conventional fall protection
Must develop and follow a fall protection plan
Plan must be kept at the site
What are Fall Protection Plan Elements?
1) Written specific to each site by a qualified person
2) Kept up to date, changes made by qualified person
3) Copy kept on site
4) Implemented by competent person
5) Document infeasibility of conventional fall protection
6) Discussion of alternative measures and why they cannot be used.(scaffolds, ladders, lifts etc.)
7) Identify locations – CAZ
8) Implement a safety monitor
9) Identify each covered employee
10) Reevaluate after fall or serious incident
What are the benefits for Prevention Through Design (PtD)?
-Concept of “designing out” health and safety risks during design and development
- Reduce risk for the people who:
- -Build the structure
- -Live or work in the structure
- -Maintain the structure
- -Demolish the structure
What are Active Fall Protection Systems?
Personal Fall Arrest Systems (PFAS)
Positioning Device System (PDS)
Restraint Systems
Lifelines (Horizontal and Vertical)
What are the ABCs of Active Fall Protection?
Anchorages
Body holding device
Components
What is a Personal Fall Arrest System (PFAS)?
A system used to stop a fall in mid-air
Has an anchorage, body harness and deceleration device
May use connectors, lanyards, and lifelines
What is a Positioning Device System (PDS)?
Body belt or body harness system rigged to
Support worker on a vertical surface
Work with both hands free
Limit the fall to no more than 2 feet
What is a Restraint System?
Keeps the worker from reaching the edge
Combination of anchorage, anchorage connectors, lanyard and body support
What is a Horizontal Lifeline System (HLL)?
Uses a horizontal line supported on posts
Connect the worker with other components
Fall arrest or travel restraint
Installed under the supervision of a qualified person
What is a Vertical Lifeline System (VLL)?
Vertical lifeline (a suspended flexible line) attached at top and bottom fall arrestor slides on the line
What are Active Fall Protection Components?
- Body Holding Device
- Anchorages
- Connectors
- Lanyards
- Lifelines
- Deceleration Devices
What is Anchorage?
-Overhead I-beams
-Davit arms
-Concrete columns
-Form work
-Reinforcingbar(Rebar)
-Manufacturedanchorattachedto structure
What are PFAS Anchorage Strength requirements?
Can support at least 5,000 pounds for each employee
OR
Is designed, installed and used with a safety factor of at least two under the supervision of a qualified person
Must support at least 3,000 pounds
OR
Twice the potential impact load of an employee’s fall
What is Evaluating Anchorage?
When you are considering an anchorage, you need to look at several factors
Design and integrity of structure
The fall protection system
Weight of worker(s), tools, and materials
Large gate hooks ______ be used for connections to the body
SHALL NOT
For a compatible connection, the _____ of the anchorage connector should be greater than (>) the _____ of the connector
‘A’ dimension
‘B’ dimension
What is Improper Snaphook Use?
Do not attach directly:
- To each other
- To a horizontal lifeline
- To webbing, rope or wire rope
What do Deceleration Devices do?
Any mechanism for fall arrest which:
dissipates a substantial amount of energy
OR
limits the energy imposed on an employee
What are the PFAS Specifications?
- 1,800 pound maximum arresting force on the employee
- Complete stop in 3.5 feet
- Rigged so the employee cannot free fall more than 6 feet and cannot contact any lower level
- Take twice the impact of an employee free falling a distance of 6 feet
What are Rescue Planning - OSHA requirements?
Provide for prompt rescue of employees in the event of a fall
OR
Assure that employees are able to rescue themselves
Provide prompt rescue to fallen persons
Written rescue procedures for
- -Self rescue
- -Assisted rescue
Suspension trauma occurs when
blood flow is restricted by the harness leg straps
Onset of Orthostatic Intolerance:
After 5 minutes:
- Straps impede blood return
- Muscle venous pump fails
- Blood becomes toxic and highly acidic
After 15 minutes:
- Lightheadedness, dizziness, confusion, ‘pre-fainting’ symptoms can occur
- Anxiety and onset of shock
- Heart rate increases
- Cardiac irritability
After 30 - 60 minutes:
- Loss of vision
- Blocked airway
- Cardiac arrest or brain damage
- Death can occur
While waiting:
DO NOT ______ OR _______
Also, ______ Harness Leg Straps
allow worker to lie flat
stand upright after rescue
loose
The ‘FALL’ Acronym:
Study on slide 189 Subpart M
What are adequate ground conditions for crane use?
Firm, drained
and graded
Sufficient to support crane (in conjunction with blocking, mats, etc.)
Controlling Entity must ___ equipment user & operator of known underground hazards
Inform
What are the two options for crane ASSEMBLY / DISASSEMBLY?
Manufacturer procedures
or
Employer procedures (criteria requirements)
Crane OPERATOR QUALIFICATION / CERTIFICATION options?
OPTION 1: Accredited testing organization OPTION 2: Audited employer program OPTION 3: U.S. military OPTION 4: State/local gov’t license
Signal Types for crane use?
- Hand, voice, audible or “new”
- Only time an operator can use a cell phone while lifting (but must be hands free)
Signal person requirements?
Point of operation not in full view of operator
View of direction of travel is obstructed
Site-specific safety concerns
Signal person Qualification Requirements:
Know & understand signals
Competent in using signals
Basic understanding of crane operation
Verbal or written test plus practical test
______ and ______ cause many injuries and fatalities among construction workers
Stairways
Ladders
About half the injuries caused by slips, trips and falls from ladders and stairways require
time off the job
There must be a stairway or ladder at points of access where there is an elevation break of _______
19 inches or more
Rails must be able to withstand a force of
200 pounds
Stairways with _________ must be equipped with at least one handrail
four or more risers, or higher than 30 inches
Stairways with four or more risers or more than 30 inches high must also have
a stairrail along each unprotected side or edge
Stairs should be installed between ___ and ___ degrees.
30
50
Stairs must have uniform _____ and _____, with less than a ____ variation.
riser height
tread depth
1/4-inch
Only use pan stairs if filled with
filler material at least to the top edge of each pan
Stairways landings must be at least
30 inches deep and 22 inches wide at every 12 feet or less of vertical rise
Unprotected sides of landings must have standard _____ guardrail systems
42 inch
Where doors or gates open directly on a stairway, provide a platform that extends at least _____ beyond the swing of the door
20 inches
Keep the area around the ____ and _____ of a ladder clear
top
bottom
Ensure rungs, cleats, and steps are _____ and ________
level
uniformly spaced
For ladders, Ensure rungs are spaced __ to __ inches apart
10 to 14
What are the ladder don’ts?
Tie ladders together to make longer sections, unless designed for such use
Use single rail ladders
Load ladders beyond the maximum load for which they were built, nor beyond the manufacturer’s rated capacity
Why do we secure ladders?
to prevent accidental movement due to workplace activity
Portable ladders must:
Be inspected before use for cracks, dents, and missing rungs
Designed or treat rungs to minimize slipping
Side rails – at least 11 1/2 inches apart
Must support 4 times the maximum load
When should a double-cleated ladder be used?
- when ladders are the only way to enter or exit a working area with 25 or more employees
- when a ladder will serve simultaneous two-way traffic
What should not be used on wood ladders?
paint and opaque covering (like varnish) on a wood ladder
For non-self supporting ladders, Position at an angle where the horizontal distance from the top support to the foot of the ladder is ___ the working length of the ladder
1/4
When using a portable ladder for access to an upper landing surface, the side rails must extend at least _____ above the upper landing surface
3 feet
Equip a fixed ladder 24 feet or longer with either a:
- Ladder safety device
- Self-retracting lifelines with rest platforms every 150 feet or less
- Cage or well, and multiple ladder sections, each section not exceeding 50 feet
If using ladders where the employee or the ladder could contact exposed energized electrical equipment, they must have
nonconductive siderails such as wood or fiberglass
Do not use the _________ as a step
top or top step of a stepladder
A competent person must inspect ladders for
visible defects, like broken or missing rungs
If a defective ladder is found, immediately
mark it defective or tag it “Do Not Use”
How should one properly climb a ladder?
Face the ladder when going up or down
Use at least one hand to grab the ladder when going up or down
Do not carry any object or load that could cause you to lose balance
Always use the ________ _______ for the job
correct ladder
Never ______ a ladder
overload
Employees must train you in proper use of a ____
ladder
Maximum allowable slope for stable rock?
Vertical (90 degrees)
Maximum allowable slope for Type A (2) soil?
3/4 : 1 (53 degrees)
Maximum allowable slope for Type B soil?
1 : 1 (45 degrees)
Maximum allowable slope for Type C soil?
1 1/2 : 1 (34 degrees)
Spoil piles need to be at a minimum of ___ _____ from the excavation hole
2 feet
What depth of an excavation is protection required?
5 feet or more
What is the maximum allowable distance to closest egress point within a trench?
25 feet
At what depth is a ladder or steps required for trench access or egress?
4 feet
Ladder must extend at least ___ ____ above their surface.
3 feet
for excavation, 3 feet above top of trench
Fall protection is required at ____ feet
6
What does I x R measure?
V : Voltage
How is Power measured?
V x I
What is the minimum voltage that can cause ventricle fibrillation?
75 mA
What is Table K-1 in Subpart K?
Working Clearances
What is the minimal working clearance (normal voltage to ground)?
3 ft^2
What is the minimum front working clearance with electricity?
3 ft
When using distance as a guard against 50 volts or more, what is the minimum elevation?
8 ft
Does electrical equipment need to be thrown out if it is broken?
No, a qualified electrician may be able to fix it
How far must a ladder extend beyond a surface?
3 ft
What is the distance in which employees must be protected against a fall in construction?
6 ft
A hole means a gap or void _____ inches or more in its least dimension
2 inches
An opening means a gap or void ____ inches or more high
30 inches
The top rail of a guardrail must be a minimum of ___ inches
39
What is the optimal heigh in inches for the top rail of a guard rail to be?
42 inches
42 +/- 3
What is the maximum free fall distance allowed?
6 feet
The top rail must be able to withstand how much force?
200 lbs
The mid-rail must be able to withstand how much force?
150 lbs
The anchorage point for RESTRAINT must be able to withstand 2x the intended load or a force of ____ lbs
3000 lbs
The anchorage point for ARREST must be able to withstand 2x the intended load or a force of ____ lbs
5000 lbs
What is the minimum distance that excavated materials, tools, and other supplies be kept back from an excavation’s edge?
2 feet
At what depth must a ladder, ramp, steps, or runway be present for quick worker exit in an excavation?
4 feet
Unless work is being done in stable rock, at what minimum depth is protective system required in a trench?
5 feet
What is the maximum distance a worker can travel to a degree point in a trench?
25 feet
What are the routes of entry for health hazards?
Ingestion
Injection
Absorption
Inhalation
What role does a competent person NOT play in scaffold work?
design
Who is in charge of design for scaffolds?
A qualified person (such as an engineer)
What’s the max exposure to noise for 8 hours?
90 dB
What is PFAS?
Personal Fall Arrest System
What is V ?
Voltage
What is I ?
Current
What is R ?
Resistance
What is P ?
Power
V =
I x R
P =
V x I
How can electricity cause harm?
- Shock
- Burns
- Falls due to contact with electricity
- Electrocution (death)
What is Ohm’s Law?
used to describe the mathematical relationship between voltage, current, and resistance
What is the ventricular fibrillation threshold?
100 mA
Ventricular fibrillation will cause death in a few minutes unless
defibrillator is used
What are the primary causes of electrocution?
- Contact with overhead powerline
- Contact with live circuits in panels
- Poorly maintained cords and tools
- Lightning strikes
What is the best way to avoid electrical harm?
Eliminate the hazards
When it comes to electricity, one must have ______ protection on construction sites
“open neutral”
Electrical protection must be provided against:
- Ground faults, the most common form of electrical shock hazard
- Fires
- Overheating
- Destruction of insulation on wiring
What is a GFCI’s?
Ground Fault Circuit Interrupters
How do GFCI’s work?
Fast-acting circuit breaker sense small imbalances in the circuit caused by the current leakage and shuts off the electricity
What are the three NEC classifications?
1) Class (material type)
2) Group (material properties)
3) Division (likelihood of hazardous atmosphere)
What is a class I NEC?
Flammable and Combustible liquids and flammable gases
What is a class II NEC?
Combustible dust
What is a class III NEC?
Ignitable fibers or flyings
What is a division 1 for NEC?
hazard generally exists during normal conditions
What is a division 2 for NEC?
hazard generally exists only during abnormal conditions
a letter designation (A-G) indicating the type of gas or dust we are dealing with
Group
What are the main ignition sources?
Arcs and Sparks
Open Flames
Hot Surfaces
What examples of arcs and sparks?
Power sources Static electricity Lightning Mechanical sparks Light-alloy enclosures
What examples of open flames?
Welding and cutting
Ovens and furnaces
What are some other sources of ignition?
Electromagnetic waves Laser Radiation Chemical reactions Stray currents
Class I equipment shall not have any exposed surface that operates at a temperature in excess of ____ of the ignition temperature of the specific gas or vapor
80%
The ignition temperature of the methane is
1112 degrees F
The maximum temperature of any exposed surface cannot exceed _______ for class I equipment
890 degrees F
All electrical systems should have a ______ so that all branches of the circuit are properly protected
short circuit evaluation
Do not use electrical equipment unless it has
- manufacturer’s name
- trademark
- descriptive marking
Guard electric equipment operating at ______ accessible only by qualified persons
50 volts or more
An assured equipment grounding conductor program should contain:
(A) Written description of program
(B) Competent person
(C) Inspect all cord sets before use daily
Inspect insulating equipment:
- prior to each day’s work
- immediately after any incident
Unqualified Person:
- know safe work distances
- recognize dangers of exposed energized parts
Qualified Person:
- know safety related work practices
- know step by step requirements necessary to provide protection
Unless identified for use in the operating environment, no conductors or equipment shall be located:
-in damp or wet locations
=where exposed to gases, fume, vapors, liquids, or other agents having a deteriorating effect on the conductors or equipment
-where exposed to excessive temperatures
What are some electrical hazards?
- Electrical shock
- Arc flash
- Arc blast
Arc Flash occurs when _____
electric current passes through air between ungrounded conductors or between ungrounded conductors and grounded conductors, the temperatures can reach 35,000 degrees Fahrenheit
Burns skin directly and ignite clothing causing secondary burns
Arc Flash
Arc flashes can cause _____ if flammable substances are present, and can create dangerous vapors
explosion
Every year over _____ people are admitted to burn centers with severe arc flash burns (NFPA)
2000
Hazards Associated with Arc Flash are:
- Heat (35,000 ºF)
- -Burns
- -Ignition of Materials
- -Molten metal
- -Copper vapor
- Second Degree Burn Threshold :
- -80 ºC / 175 ºF (0.1 sec), 2nd degree burn
- Third Degree Burn Threshold:
- -96 ºC / 205 ºF (0.1 sec), 3rd degree burn
- Intense Light
- -Damage eyes – cataracts
What is an Arc Blast?
Extreme temperatures of the electrical arc cause explosive expansion of both the surrounding air and the metal in the arc’s path
The sudden expansion of an arc blast creates
- Extremely high air pressures
- Loud sound
- Shrapnel and molten metal that fly at speeds exceeding 700 mph
What effects do Arc Blasts have on the body?
- Pressure can knock you off your feet and collapse your lungs
- The sound (as loud as 160 dB) can rupture ear drums
- Flying material and molten metal can burn you and penetrate deep into your body
_______ is red and sensitive to touch. There is minimal skin damage and only the skin surface is involved
First Degree Burn
_______ involves the first and second layers of skin. The skin reddens intensely and blisters develop. Severe pain and swelling occur and chance for infection is present
Second Degree Burn
_______ causes charring of skin and coagulation of blood vessels just below the skin surface. All three layers of skin are affected. Extensive scarring usually results
Third Degree Burn
Elements of Safe Electrical Work Practices
- Safety principles
- Program controls
- Rules for working on or near live parts
- A hazard evaluation procedure
- -Used to calculate the risks before you begin work on or near live parts operating at 50 volts or more
- Job briefing requirements
- Job briefing checklists
Equipment is ____ and _____ be energized
not
cannot
Circuit or part to be worked on or near is:
- Disconnected from energized parts
- Locked and/or tagged so it can’t be energized unexpectedly
- Tested to make sure there is no voltage
- Grounded if necessary
an assessment performed by your employer to determine the voltage, boundary requirements, and personal protective gear needed to prevent electrical shocks; determine approach boundaries
Shock Hazard Analysis
determines the risk of arc flash, sets a flash protection boundary based on incidence energy, and list required PPE and other safety measures
Flash Hazard Analysis
What is a Flash Protection Boundary?
The distance from exposed live parts within which you can get a second degree burn if an arc flash occurs
In most systems of 600 volts or less, the Flash Protection Boundary is
four feet
A mathematical formula is used to
calculate the boundary at higher voltages and for various fault currents and clearing times
Personal Protective Equipment, PPE, for the arc flash is
the last line of defense
Third party qualified evaluator
Documentation - Yes
Portable - Yes
Employer qualified evaluator
Documentation - Yes
Portable - Yes
Operations procedures must be developed by a qualified person
when the manufacturer’s procedures are unavailable
Procedures related to the capacity of the equipment must be developed by a __________ (familiar with the equipment) when the manufacturer’s procedures are unavailable
registered professional engineer
When workers must be in the fall zone to handle a load, the load must be rigged by
a qualified rigger
OPERATOR QUALIFICATION / CERTIFICATION Options:
1) Accredited testing organization
2) Audited employer program
3) U.S. military
4) State/local license
What are the types of crane inspections?
- Modified or repaired/adjusted
- Post-assembly
- Shift
- Monthly
- Annual
Modified or repaired/adjusted
Qualified person
Post-assembly
Qualified person
Shift
Competent person
Monthly
Competent person
Annual
Qualified person
What is total fall distance?
18.5
What are the factors that go into the 18.5 requirement?
6 feet: height of worker
6 feet: free fall lanyard
3.5 feet: deceleration distance
3 feet: clearance
What is the difference between a Personal Fall Arrest System and a Personal Fall Restraint System?
A personal fall arrest system keeps the worker from hitting the ground and getting injured or dying at the result of a fall while a personal fall restraint system keeps the worker form even entering the fall zone and prevents the fall from occurring
What is the difference between an excavation and trench?
OSHA defines an excavation as any man-made cut, cavity, trench, or depression in the Earth’s surface formed by earth removal. A trench is defined as a specific type of excavation, a human-made narrow surface cavity that is deeper than it is wide and is less than 15 feet wide
What is the role of competent person for excavations?
- Required training and knowledge
- -Soil classification
- -Use of protective systems
- -OSHA’s requirements for excavation
- Able to identify hazards and have the authority to eliminate hazards
When must inspections must be made for excavation work?
- Before work begins.
- After rainstorms, high winds, or other occurrences that may increase hazards.
- When it can reasonably anticipated that a worker will be exposed to hazard(s).
What is the greatest hazard for excavations?
Cave-ins pose the greatest risk and are much more likely than other excavation related accidents to result in worker fatalities
One cubic foot of soil weighs between
90-130 lbs
Never enter an unprotected trench that is ____ in depth
5 or more feet
The competent person must first choose and implement
a protective system
Even excavations less than 5 feet deep need to be _____ by the competent person
deemed safe
What are types of Protective Systems for excavations?
- Support/shoring systems
- Sloping and benching
- Shielding systems (trench boxes)
if designed and installed correctly, prevents movement of the excavated wall
Shoring
removes the risk of cave-ins by sloping the soil of the trench back from the trench bottom
Sloping
are designed to protect workers from the forces of a cave-in
Trench shields and boxes
Structures become unstable when
earth next to them is removed
Before starting work, the OSHA standard requires your employer to do the following:
- Determine the approximate location of utility installations—sewer, telephone, fuel, electric, and water lines; or any other underground installations
- Contact the utility companies or owners involved to inform them of the proposed work within established or customary local response times
- Ask the utility companies or owners to find the exact location of underground installations. If they cannot respond within 24 hours (unless the period required by state or local law is longer) or cannot find the exact location of the utility installations, you may proceed with caution.
What is a spoil pile?
excavated or other materials or equipment that could pose a hazard by falling or rolling into excavations near the edge of the excavation
When mobile equipment is operated adjacent to an excavation;
the operator must have a clear and direct view of the edge of the excavation, or… A warning system shall be utilized such as barricades, hand or mechanical signals, or stop logs. If possible, the grade should be away from the excavation
Employees exposed to public vehicular traffic shall be provided with, and shall wear
warning vests or other suitable garments marked with or made of reflectorized or high-visibility material
A competent person must test any excavation deeper than ______ or where an __________ or could reasonably be expected, such as a landfill or where hazardous substances are stored nearby, before an employee enters it
4 feet (1.22 meters) oxygen deficiency or a hazardous atmosphere is present
Water changes everything and
makes soil less stable
What degrees of access/egress should ramps be used?
0 - 20 degrees
What degrees of access/egress should stairs be used?
30 - 50 degrees
What degrees of access/egress should ladders be used for substandard use?
60 - 75 degrees
What degrees of access/egress should ladders be used for preferred use?
75 - 90 degrees
_____ must be worn in excavations because of overhead hazards
Hard hats
During excavations, employers must:
- preplan the work and use the one-call system to identify underground utilities
- protect you from cave-ins and other excavation-related hazards
- inspect the excavation at least daily and throughout the shift as needed
- take prompt corrective action when a hazard is identified
- respond to and correct hazards pointed out by you, the worker
- make sure a ladder is within 25’ of your work area when deeper than 4’
- keep excavated dirt, rocks and other materials back 2’ from the excavation’s edge
- Test and monitor the air within the trench in areas suspect to atmospheric hazards
If a trench box or shoring is used, never
leave its protection while in the trench
What is the minimum distance that excavated materials, tools, and other supplies be kept back from the excavation’s edge?
2 feet
At what depth must a ladder, ramp, steps, or runway be present for quick worker exit:
4 feet
What is the greatest hazard facing a worker while working in a trench:
cave-ins
Unless made in entirely stable rock, at what depth is a protective system required for a trench:
Any depth if the competent person says so
and
5 feet deep and greater
Almost _____ scaffold related injuries annually
10,000
Over __ scaffold-related fatalities annually
75
Trigger height for fall protection for scaffolds is
10 feet
What is guardrail height when primary its the primary fall protection?
38 inches
__ inch when guardrails required and fall arrest used (e.g.: suspended scaffolds)
36
________ determines Fall Protection feasibility for erectors and dismantlers
Competent Person
Scaffold Competent Person must have:
Knowledge of structural integrity
Maintenance of scaffolds
Effects of potential hazards
Knowledge of standard
General RequirementsFor All Scaffolds
- support own weight and 4 X the maximum intended load.
- suspension rope & hardware, 6 X the maximum intended load.
- stall load of scaffold hoist not to exceed 3 times its rated load.
- designed by a qualified person and built and loaded to design
Scaffold platform construction requirements
- Platforms fully planked or decked
- -no more than 1” gaps
- -maximum openings of 9½”
- -scaffold platforms and walkways 18” wide
- -ladder jack, top plate bracket, roof bracket, and pump jack scaffold at least 12” wide
- -guardrails and/or personal fall arrest systems for platforms and runways not 18” wide
Two of the most common scaffold violations:
No guardrails
Safe access not provided
Scaffold access requirements
- Must have safe access
- No access by cross braces
- Bottom rung not more than 24” high
- Rest platforms at 35’ intervals
- Sets access requirements for erectors and dismantlers ( September 2, 1997)
- Can use some end frames for access
_____ can be used in lieu of guardrails on some scaffolds
PFAS
Toe boards should be at edges of platforms because of
falling object protection
Common Sources of Scaffolding Hazards
- Bases
- Bracing
- Scaffolds Loads
- Working Loads
An aerial lift can be used to
work safely at elevations
PPE is the ___ level of control
last
Engineering Controls:
- Physical changes to workplace
- -Isolation
- -Ventilation
- -Equipment modification
Administrative Controls:
- Requires worker to do something
- -Proper procedures
- -Inspection and maintenance
- -Housekeeping
- -Supervision
- -Regulated areas
- -Limit exposure by time or distance
Employers must ensure that their employees wear head protection if any of the following apply:
- Objects might fall from above and strike them on the head
- They might bump their heads against fixed objects, such as exposed pipes or beams
- There is a possibility of accidental head contact with electrical hazards.”
What are the classes of hard hats?
G,E,C
General
Electrical
Conductive
Class G (General) Hardhats:
General service (e.g., building construction, shipbuilding, lumbering, and manufacturing)
Good impact protection
Limited voltage protection(proof-tested at 2,200 volts)
Class E (Electrical) Hardhats:
Electrical work
Protect against falling objects
Protect against high-voltage shock/burns (proof-tested at 20,000 volts)
Class C (Conductive) Hardhats:
Designed for comfort, offers limited protection
Protects heads that may bump against fixed objects
Does not protect against falling objects or electrical hazards
Common Causes of Eye Injuries:
- Dust
- Flying particles
- Harmful chemicals
- Intense light
- -Welding
- -Lasers
Safety Glasses protect against:
Flying particles from wood, metal, cement, plastics, or other materials
Airborne particulates such as ashes, dust, embers, sand blast, grit, paint, or other materials
Goggles protect
eyes, eye sockets and facial area around eyes from impact, dust, & splashes
Welding Shields:
- Protect eyes from burns
- -Infrared light
- -intense radiant light
- Protect face and eyes from
- -flying sparks
- -metal spatter slag
Shields are for face protection, not
eye protection
Exposure to over ____ can cause hearing loss
85 dB
Hearing protection required at
90 dB
Employers must provide hand protection when employees are exposed to hazards
- Skin absorption of harmful substances
- Severe cuts or lacerations
- Severe abrasions
- Punctures
- Chemical and thermal burns
- Harmful temperature extreme
What are the different types of gloves?
Anti-vibration, leather palm, permeating resistant, heat resistant, cut resistant
Causes of Foot Injuries:
- Heavy objects
- Sharp objects
- Molten metal
- Hot surfaces
- Slippery or wet surfaces
- Electrical hazards
Causes of bodily injuries:
- Intense heat
- Splashes of hot metals or hot liquids
- Impacts from tools, machinery, or materials
- Sharp objects
- Hazardous chemicals
- Contact with potentially infectious materials
- Radiation
Employers must in terms of PPE:
- Assess hazards
- Select appropriate PPE and determine when to use
- Provide some PPE at no cost to employee
- Make sure that employee-owned PPE is adequate, properly maintained and sanitary
- Train employees and enforce use of PPE
Who is responsible for providing PPE?
The employer
Safety controls must meet the following order of priority:
Substitution, engineering, administrative, and PPE
Which type of hard hat would provide the most protection from electrical hazards?
Class E
Who is responsible for providing specialized work footwear?
The employer
Which of the following is considered approved eye protection?
Glasses meeting ANSI standard Z87