Safety hazards and accident prevention for building contractors, homeowners, building inspectors & workers:
Here we list and describe common home & building safety hazards described & illustrated for homeowners, building owners, home inspectors.
We include tables of accident frequency by type or cause, and we discuss and illustrate many common building dangers such as stair falls, ladder safety, electrical and environmental hazards, animal hazards, even encounters with deranged armed occupants in buildings.
But equally important as watching out for the obvious, is our approach to inspecting or working on or in buildings, mechanical systems, and the indoor environment.
Page to photo: dangerous, collapsing parking lots and buildings were still falling when ASHI home inspectors served the American Red Cross by providing building safety inspections following the Northridge Earthquake. Inspectors as well as residents faced very dangerous conditions including structural collapse, fire, electrical shock, gas explosions, and more.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
- Daniel Friedman, Publisher/Editor/Author - See WHO ARE WE?
Daniel Friedman, Connecticut Association of Home Inspectors Education Seminar - 03/26/2008 (updated to 2018)
Abstract: Accident prevention for home owners and home safety inspectors: the purpose of this free online home safety course and the accompanying home safety hazard checklist at
InspectaAPedia.com/home_inspection/Building_Inspector_Safety_Risks.php is to reduce the chance of serious injury or death for home inspectors, other building inspectors, and building occupants.
We review common and high-risk safety hazards in homes.
These risks are of particular concern to the home inspector who may be exposed to more varied and extreme conditions than other visitors to a building or site.
We provide clues for recognizing latent or "hidden" hazards, we set priorities of concern, identify strategies for recognizing safety hazards that may not otherwise be obvious, and and we suggest building inspection and reporting procedures that can reduce the accident rate in buildings.
Photo above: during repairs of a church in Guanajuato, Mexico, a worker steadies a ladder whose bottom feet rest atop a table.
Catalog of Home Safety Hazards for Building Inspectors, Home Inspectors, & building occupants
The range of hazards faced by home inspectors in the course of examining buildings is considerable.
It includes obvious catastrophes such as falling off of a roof or electrocution, and less obvious or less likely events such as structural collapse, exposure to bacterial hazards, fungal hazards, or even physical attack by violent building occupants, biting dogs, sneaky snakes, and pecking parrots.
Home inspectors and other professional building diagnosticians are expected to be observant and attentive to detail. Despite these skills, accidents happen to inspectors.
Home inspectors and other building investigators and workers spend a lot of time on ladders. Our photographs illustrate some of the crazy things people do to gain ladder access to areas of buildings.
Just above, a ladder catapult has been designed and placed into use in Tapalpa, Mexico.
A Canadian home inspector fell to his death during a roofing inspection. He was ascending a high ladder which he suspected was unsafe.
Following a home inspection in New Paltz, NY, Ballinger, a real estate agent who was angry with the results of the inspection, attacked and attempted to kill Steve Vermilye by driving his car off of the pavement, across a sidewalk, crashing into a building wall where Vermilye was walking. Another home inspector was badly injured when an attic fold-down stair fell out of its opening as the inspector was climbing it.
Hazards that an inspector should recognize affect other people too. An aggressive tenant threatened two elderly inspection clients with a rifle and then showered them with stones. An electrical inspector was killed by an electrical arc explosion while removing the cover of an electrical panel. A plumber was killed while leaning over a water pressure tank that, lacking a pressure relief valve, exploded.
We will list some of the more egregious and more interesting of these dangerous building hazards, review accident case histories, and we will illustrate procedures of attention, observation, and hazard recognition that can reduce the chances of accidents during building inspections.
General classes of accident during a building inspection can be understood as having two underlying causes:
We are more afraid of improbable hazards beyond our control (EMF) than we are of probable hazards over which we have control (smoking cigarettes). For example we (DF) have had clients who were very frightened about possible indoor air quality issues in their home.
But we discovered they were heavy smokers. Another smoking client told me that she does not expose her children to cigarette hazards since she does not smoke inside their home. But we discovered that she smokes constantly when in the family car driving with her children.
The risk of falling off of a roof is a hazard. Actually falling off of a roof is an accident.
We are exposed to a wide variety hazards at widely varying risks. Some accidents are more or less likely to occur than we believe. Some accidents are likely to result in greater or lesser degree of injury than we believe. Having a more accurate picture of where hazardous risks lie can help us learn to properly attend accident risks and thus to avoid accidents.
Even an apparently improbable event (being struck by lightning) deserves careful attention in some circumstances (you're on the golf course) if the cost of the occurrence is high (death). Further, the probability of an event (being struck by lightning) varies enormously with circumstances (you're indoors).
Total Risk = (Probability of Occurrence) x (Cost of Occurrence)
The attention we pay to various risks needs to be adjusted continuously as we move through a building from area to area (basement to roof) and topic to topic (plumbing to electrical).
Tune risk recognition to area and system: The home inspector's recognition of risks needs to attend the hazards peculiar to each building area and system.
Educate to improve hazard recognition and to teach safe inspection procedures: The level of inspector technical education affects the inspector's ability to recognize hazards and to reduce accidents.
The accident rate of injury by slipping, tripping, or falling is among the highest facing home inspectors and home owners.
The hazard level varies widely from unlikely: (such as 1/8" difference in an uneven concrete slab on either side of a crack) to severe (such as an improperly placed ladder accessing a high roof on a windy day while reaching far out to one side to photograph a roof defect while standing on an unsecured ladder).
(Drawing below is used for educational purposes only).
TYPES of ACCIDENTS: NUMBER OF INJURIES SUSTAINED IN THE UNITED STATES | ||||
CAUSES | FATALITIES | HOSPITALIZED | NON-HOSPITAL | LIFETIME COST (Billion $) |
Motor Vehicles | 45,923 | 23,028 | 4,803,000 | $48.7 |
Falls | 12,866 | 783,357 | 11,493,000 | 37.3 |
Firearms | 31,556 | 65,129 | 171,000 | 14.4 |
Poisonings | 11,894 | 218,554 | 1,472,000 | 8.5 |
Fires/burns | 5,671 | 54,397 | 1,403,000 | 3.8 |
Drownings | 6,171 | 5,564 | 26,000 | 2.5 |
All others | 28,487 | 696,707 | 35,001,000 | 42.4 |
Total injuries | 142,568' | 2,346,736 | 54,369,000 | |
Lifetime cost | $49.4 | $80.0 | $28.2 | $157.6 |
Percent of total lifetime cost | 31 | 51 | 18 | 100 |
1 Cost of Injuries in the United States and the Role of Building Safety, Jake Pauls BUILDING STANDARDS/July-August, 1991
This safety hazard pattern has shifted since about 1996 to reflect significant increases in mortality due to drug overdose and firearms. In fact, by the end of 2011 in the U.S. at least, the New York Times reported that for the first time, the U.S. Centers for Disease Control had found that drug overdoses represented the leading cause of accidental death, overtaing motor vehicle accidents.[2] However falls remains a very high risk and one which receives less attention than it deserves.
"Falls include both falling to another level -- as in falling from stairs, ladders & windows -- or same level falls such as slipping, tripping & stumbling. Deaths from falls were highest in Hungary, the Czech Republic, Norway, Slovenia & Finland -- and lowest in Albania, Mauritius, Bahamas, Argentina & Chile. (Countries listed in order of death rate.)" Reference: Causes of Death, Ben Best
2002 ACCIDENT DATA: TYPES OF DEATHS 2 | ||
ACCIDENT | PERCENT | |
1 | Motor Vehicle | 44.3 |
2 | Falls | 17.8 |
3 | Poisoning | 13 |
4 | Drowning | 3.9 |
5 | Fires, Burns, Smoke | 3.4 |
6 | Medical Surgical Complication | 3.1 |
7 | Other land transport | 1.5 |
8 | Firearms | 0.8 |
9 | Other (non-transport) | 17.8 |
2 National Vital Statistics Report, Volume 50, Number 15 (September 2002
Falls:
The highest risk of injury by falls occurs among the elderly. "Falls represent the most frequent non-transportation related accidents occurring among older adults and are the leading cause of home fatalities for this population. Stairways are particularly hazardous for the elderly.
Other types of falls include slipping in bathtubs and showers, slipping on tile or icy terrain, and tripping over objects on the floor. Falls associated with getting in and out of bed, getting on or off a chair, or using the bathroom are also frequent.
Burns:
are also common among older people. In fact, burns and other consequences of fire rank second as a cause of death among persons aged 65+. Among activities that lead to burns are cooking, smoking, and accidentally turning on and failing to turn off appliances. Scalds from hot water are also a frequent source of injury, especially in bathtubs and showers.
Poisoning:
from improper doses of medication ranks third as the most prevalent type of home accidents. [Poisoning fatalities and hospitalizations have increased dramatically in the U.S. recently in association with illegal drug use. --DF]
Older people are especially susceptible to this kind of occurrence as they are likely to be taking several highly potent drugs at one time, to have visual or cognitive disabilities, and to live in environments that are conducive to medication errors (e.g., environments that are poorly lit).
The high rate of home accidents among older persons:
points to the need to understand the etiology of these accidents so that we can develop design interventions.
The reasons for the high frequency of such accidents are complex but are likely to include the fact that older people spend most of their time at home and that age-related changes in functional abilities make it more difficult for them to complete home tasks.
Moreover, the demands of the home environment are often substantive in that the homes of elderly people tend to be older than those of younger people, more difficult to operate and maintain, and more often in need of repair.
As a result, housing deficiencies, such as broken stairs or poor electrical wiring, are more common in elderly housing."
Reducing slip, trip, and fall hazards for home inspectors is discussed within individual building area and hazard topics which follow.
Canadian home inspector fatality, inspector ascending exterior ladder secured to building knew the ladder was unsafe, told his wife he was afraid of it but felt he had to ascend to inspect the roof during a multi-day inspection of a large building.
The ladder came away from the building and the inspector fell to his death. (Ca. 1998)
Stunning stairs, remarkable railings, loopy ladder tricks.
The author has consulted in depth concerning fall injuries and has performed case studies investigating stair and rail accident and injury lawsuits.
American home inspector injury: inspector ascending or descending an improperly-secured attic stair was badly hurt when the stair came out of its opening and fell. Falling tangled in a stairwell increases injuries.
Investigation of the stairwell wall found evidence of removed railings tenant falls, no railing-removed by landlord; tenant falls, sues building owner.
Landlord responded to tenant's complaint of loose railing by removing it entirely.
Inspection confirmed that the stairway railings had been removed in one case (photographic evidence of wall modification confirmed separate testimony) and stair railings had been improperly installed (secured only to drywall) in a second case.
Note bad steps and rails to yourself and report orally and in writing to your clients
Ladder angle (OSHA: the horizontal distance from the top support to the foot of the ladder should be approximately one-quarter of the working length of the ladder)
At DEBRIS STAINS on ROOFS I comment that climbing onto this roof in Two Harbors MN in order to remove accumulated debris placed me smack into an area where there was already an accumulation of hemlock needles just hoping they could send me back down to earth in a hurry.
Below: workers in Mexico are using wood scraps to shim the uneven surface below the bottom of a ladder.
Below: in one of my favorite ladder photos workers in San Miguel de Allende needed a taller ladder than what was at hand, so the ladder was set atop a table. This is not an OSHA-approved ladder procedure.
Unsafe attic stairs
REF: http://www.aachenconsultancy.co.uk/index5.html on work accident claims
Watch out for snakes: I encountered a crawl space with snakes here in AZ not a huge surprise but after I had to leave the crawl space rather rapidly, the home owners informed me that they had them put snakes in the crawl area to take care of a rat problem!
But this leads to a useful lesson for Arizona home inspectors: ask all parties if they know of any "proactive measures for rodent control " that have been applied to the space below the building before you enter such an area.
The snake handlers had to be called out and then the crawl space was ready to be inspected!
That was not an isolated incident.
The author inspected a mold-contaminated reptile vendor's property in Orange County New York. The owner had died. His wife entered a few days after the funeral to feed the turtles, snakes, iguanas. A boa constrictor had found its way into the ceiling, from where it dropped onto her and encircled her neck.
The owner won the battle, escaped the snake, locked the doors and never went in again.
At my [DF] inspection the reptiles were long dead. They had been succeeded by leaks and mold growth enough to make even a suited-up environmental test expert sick.
The most common injury associated with lifting is back pain. It is said that up to 5 million working days are lost due to back pain every year.
REF: http://www.aachenconsultancy.co.uk/index4.html
New York City worker found dead in duct system after falling through a ceiling and remaining trapped over a weekend.
Watch out: Contractor's ladder blew down, trapped on high roof on weekend (cut hole through to interior)
Here we give some tips on how to inspect the electrical panel, including the risks of relying on test instruments (resistance drops do not equal bad connections).
See details at SAFETY for ELECTRICAL INSPECTORS
Also see HOW TO TURN OFF ELECTRICITY in a building that has been wet or flooded - separate article
See details at SAFETY for ELECTRICAL INSPECTORS
Standing water, wet floors - do not touch electrical components
Loose wires not capped, arcing hazards during inspection
Spring-loaded panel covers may permit bus assembly to move when cover or inner panel face is removed - arc explosion hazard.
https://InspectAPedia.com/electric/Electrical_Panel_Inspection.phpHow to Inspect Residential Electrical Panels
"Lightning as a cause of death seems to excite a disproportionate amount of interest, associated with the mistaken idea that it is a random, uncontrollable natural event. Lightning is comparable to floods as a storm-related cause of death in the US.
In a given year the chance of being struck by lightning is about one in 700,000 and the chance of being killed by lightning is less than one in 6 million in the United States. But the chance is far less where thunderstorms are infrequent, such as in San Francisco and far greater where thunderstorms are frequent, such as in central Florida.
The chances are far greater for avid golfers who refuse to leave the golf course when a thunderstorm is approaching. A safe location should be sought immediately whenever the sound of thunder follows lightning by less than 30 seconds.
Avoid high places, open areas, bodies of water, metal fences and isolated trees or poles. In a house, avoid contact with
plumbing or electrical fixtures. A vehicle can be a safe shelter if the
windows are rolled-up and there is no contact with metal surfaces."
-- Ref: Causes of Death - Ben Best
Gas tank or gas piping leaks are a potential explosion or fire hazard. There may also be carbon monoxide or other asphyxiation hazards from equipment malfunctions.
https://InspectAPedia.com/plumbing/Gas_Controls_Piping_Valves.phpHow to Check Gas Piping, Controls, Regulators & LP Gas Tank Defects
https://InspectAPedia.com/plumbing/Gas_Leak_Detection.phpHow to Identify & Correct LP Gas or Natural Gas Leaks
https://InspectAPedia.com/heat/Heating_Safety_Inspection.php Heating Inspection Safety Guide
See SAFETY, HEATING INSPECTION
Also see these heating safety-related recall notices
Collapse Accidents and Hazards of Special Risk to Home Inspectors & Home Owners.
Masonry structures
such as this carriage house in Saugerties, NY, can be very unstable and risk sudden even imminent sudden collapse, depending on just how it is damaged.
Broken bond courses in brick are a particular concern as are severely-bowed masonry block walls. Discouraged about other inspection defects, SV's realtor kicked the brick foundation asserting that at least the foundation was salvageable. The building collapsed.
Wood framing and sheathing,
especially unsafe roof framing or rotted sheathing (Donna Smith fell through roof); this is an argument for inspecting in the attic first but certainly for being alert for old worn roofing or areas of probable leakage, and stepping carefully when walking a roof of any type;
The author inspected this deck and warned of its probable collapse, indicated that it was dangerous, informed the client to "stay off of the deck" until it was repaired.
The client moved into the new home, invited friends to celebrate, partied on the deck, and rode it to the ground as it collapsed.
Six people were hospitalized (none with serious injuries). Children playing below the deck as it collapsed ran to safety.
The author re-inspected the collapsed deck to photograph construction details that led to the structural failure of this component. Litigation was broached.
See details at STRUCTURAL COLLAPSE HAZARDS
Inspection Hazards at Septic Systems, Drywells, Cesspools
Collapsing covers over tanks, cesspools, drywells, especially wood, steel, or home-made Collapsing site-built septic tanks, cesspools, drywells.
Particularly dangerous are unsafe covers, home made, rusted steel, wood; cesspools, particularly site-built of dry-laid stone or block, especially if "serviced" by pumping which undermines the walls;
Steel cover cuts lead to severe infections.
Bacterial (sewage) and fungal (mold) hazards for home inspectors may be present if there has been sewage backup.
Methane gas explosions & Asphyxiations at Septics
Hand-Dug wells may also have unsafe covers.
Old hand-built septic systems and covers are at extra risk of collapse after:
This home made septic tank next to the foundation and stairs had about 200 gallons capacity; a sump pump (foreground) was used to pump effluent to an uphill home-made drain field.
A manual switch operated the pump; leaky piping sprayed septic-dyed effluent over certain bystanders during the inspection.
Other causes of septic collapse include:
Case study 2002. System "serviced" improperly (a failing cesspool was rejuvenated by aerating and agitating its bottom), owner walked over system next morning, was buried alive in a collapse.
Other unsafe covers, Septic Fatalities, fatalities in CA; recent report by email of an owner's visitor stepping into the septic tank
SEPTIC & CESSPOOL SAFETY - Septic & Cesspool Safety Procedures
SEWER GAS ODORS - Diagnosing and Curing Sewer Gas Smells and Septic Tank Odors
SEWAGE BACKUP, WHAT TO DO - Sewage or Septic contamination in buildings - Investigation, Testing and Remediation
SEWAGE PATHOGENS in SEPTIC SLUDGE - Residential Septic Tank Sludge and Scum - what pathogens and contaminants do they contain?
SEWAGE & SEPTIC CONTAMINANTS
Septic system contaminants: identifying water and soil contaminants produced by onsite waste disposal systems
Rusting oil tanks
are a possible collapse hazard, though without being full of
sewage are perhaps a less odious hazard.
Buried oil tanks
or other tanks near a foundation are also a source of water entry, channeling ground water towards the
foundation.
Sink Holes,
usually known ahead of time by area when based on geological conditions; others occur due to sudden subsidence following plumbing leaks or other site changes.
Problematic and larger mold reservoirs may be present; risk varies by extent, history, location of leaks, building materials used, mechanical disturbance of moldy materials, other factors.
How to recognize problem molds and cosmetic molds by visual inspection - is it possible? Learn to recognize obviously cosmetic-only mold infections such as BlueStain.
What level of mold exposure is likely to be a risk to home inspectors? More than 30 sq .ft. of highly-airborne-type mold or even small areas of toxic mold if touched to an open cut or an eye.
Reference:
COSMETIC MOLD, RECOGNIZE
When to suspect mold or fungal contamination when no mold is visible:
Reference:
https://InspectAPedia.com/mold/Find_Invisible_Mold.php How to Find Hidden Mold
Wear a HEPA (and preferably also an organic vapor filtering double-canister) respirator.
Paper dust masks (except the 3M N-95) are ineffective and thus dangerous. Repeated exposure to mold or other allergens can lead to increased sensitization, adult-onset asthma (DF), and even sudden and severe asthmatic attacks and anaphylactic shock (hearing booth client).
https://InspectAPedia.com/mold/Mold_Action_Plan.php Mold Action Guide: What to do about mold, mildew, and other indoor allergens
https://InspectAPedia.com/sickhouse/IAQ_Investigation.php When to hire a professional to investigate a building for toxic mold
https://InspectAPedia.com/sickhouse/Stains_Not_Mold.php Stuff that is Not Mold or Stuff that is Harmless Mold
https://InspectAPedia.com/mold/Mold_Test_Method_Validity.php Mold Prevention: a guide to mold-resistant construction
Dealing with violent or threatening building occupants, dogs, spiders, snakes, rats, other pests; weapons, threats, realtors. When and how to leave a threatening environment. How to get the inspection done.
Note: For reasons that will be apparent, I do not have photographs of these encounters.
Assess the level of risk, monitor and change the assessment as needed Maintain professionalism, calmness, do not respond to hostility. As a professional guiding clients through a building:
Ask that dogs be off premises or confined in areas not to be entered during the inspection. Same for other potentially dangerous or hard to control pets.
Do not permit owner's pets to escape, be lost, injured.
Owner's dog bit DF, giving the death bite by latching onto his calf and twisting its head to try to tear off a mouthful off leg flesh. On asking the owner to put the dog out of the way, and perhaps afraid of liability, she expressed amazement.
"I can't understand it, he never bites anyone" she exclaimed.
But her eight year old daughter, standing a few feet away told a different storry.
"Mommy!" she exclaimed: "that's not right. He bites everybody!".
Owner's dog biting clients, jumps out window -
(DF- Newburgh NY). We shut the dog in a bedroom to stop it from biting our inspection clients. The dog jumped out the window onto the roof of a porch below.
It was a hot summer day; the dog was found whining and lifting its feet off of the hot metal roof - we rescued it of course.
Owner of snake farm died
(toxic mold, respiratory illness), owner operated exotic snake business in premises (DF - Orange County). Owner died, wife went in to feed the reptiles, and a boa constrictor fell onto her shoulders from its hiding place in a suspended ceiling.
The wife was so terrified she never returned to the building, leaving all of the animals to die, in turn creating a mold and health hazard for people living in apartments upstairs.
Leave the premises if:
Contact: owner, realtor(s), attorneys, and if appropriate, police;
Do not return to the property without assurance that the potentially dangerous party is not on and will not be on or at the premises
What is the Right or Obligation of a Licensed Home Inspector to
The "last man in the building" is typically held responsible for subsequent catastrophes such as exploding equipment, fires, shocks, collapses. A professional is expected to be able to observe, evaluate, and act appropriately.
The balance between risk of damage to property, possible fire, explosion, shock, or fatality, versus inconvenience to occupants or risk of freeze-damage:
Please see ELDERLY & VETERANS HOME SAFETY for the full-text version of this article. A summary is just below.
The author's mother, at age 91, fell down carpeted stairs in her home in Boca Raton, Florida. Injuries from falls can be very serious, even fatal to more fragile elderly people.
At 2AM mom decided to carry an armload of clothes downstairs to her washing machine.
Wearing open-heeled slippers with smooth soles, carrying an armload of laundry with both arms full, and stepping down stairs that were poorly designed with narrow treads and thick soft nosed carpeting, she lost a slipper and fell.
Mom's injuries included three broken ribs, an elbow so severely broken that an elbow replacement was required, and multiple lacerations to her head.
The author's neighbor, at age 85, made a wrong turn in an upstairs hallway after using the bathroom late at night.
Dr. S. fell down stairs to a landing, narrowly-missing a fatal fall through a window located at the landing, and while he recovered, his injuries were so severe, both mental and physical, that he had difficulty walking and rarely left his home again until his death years later.
Falls like these are so severe that they can materially affect the length and quality of life for the elderly. Yet the hazards involved could be easily spotted by an experienced home inspector or home safety inspector.
In a home safety article "Making Home a Safer Place, Affordably" by Lesley Alderman and appearing in the New York Times (July 2009), Alderman provided some excellent home safety inspection and home safety improvement financing suggestions that we summarize here:
...
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In addition to any citations in the article above, a full list is available on request.
Accident Frequency, Place of Occurrence, and Relation to Chronic Disease, Selwyn D. Collins, F. Ruth Phillips, Dorothy S. Oliver
Marguerite Keller, The Milbank Memorial Fund Quarterly, Vol. 33, No. 2 (Apr., 1955), pp. 199-203 doi:10.2307/3348401 This article consists of 5 page(s).
The Denominator Blindness Effect: Accident Frequencies and the Misjudgment of Recklessness, W. KIP VISCUSI
Vanderbilt University Law School; National Bureau of Economic Research (NBER); Vanderbilt University - Department of Economics; Vanderbilt University - Owen Graduate School of Management RICHARD J. ZECKHAUSER, Harvard University - John F. Kennedy School of Government; National Bureau of Economic Research (NBER) October 2002, Harvard Law and Economics Discussion Paper No. 387
"People seriously misjudge accident risks because they routinely neglect relevant information about exposure. Such risk judgments affect both personal and public policy decisions, e.g., choice of a transport mode, but also play a vital role in legal determinations, such as assessments of recklessness.
Experimental evidence for a sample of 422 jury-eligible adults indicates that people incorporate information on the number of accidents, which is the numerator of the risk frequency calculation.
However, they appear blind to information on exposure, such as the scale of a firm's operations, which is the risk frequency denominator. Hence, the actual observed accident frequency of accidents/exposure is not influential."
http://www.benbest.com/lifeext/causes.htmlCauses of Death, Ben Best
Implementation of Safety and Health on Construction Sites: Proceedings of ... by Amarjit Singh, Jimmie Hinze, Richard J. Coble Published 1999 Taylor & Francis Building sites ISBN 9058090361