Exam1 Flashcards
OSHA incidence rate
number of lost work days * 200,000hr / total hrs worked by all employees during period covered
Management of Change
requires review and authorization of proposed changes prior to implementation to ensure no unforeseen hazards are introduced. Also, all pertinent documentation including worker training must be kept up to date with regard to any changes implemented.
IDLH
Immediately Dangerous to Life or Health; “poses a threat of exposure to airborne contaminants when that exposure is likely to cause death or immediate or delayed permanent adverse health effects or prevent escape from an environment”
Teratogen
an agent or factor which causes birth defects
Hepatotoxic
damaging or destructive to liver cells
Nephrotoxic
damaging or destructive to the kidneys
FAR
No.Fatalities*10^8 hr / total hrs worked by all employees during period covered
FVC
forced vital capacity; total volume exhaled into a spirometer
Dermatoxic
damaging or destructive to skin cells
Neurotoxic
damaging or destructive to nervous system
Mutagen
causes chromosome damage
BI
business interruption = (lost profit) + (fixed cost)
Latency
time interval between the stimulation and response
Mutagen
causes chromosome damage
Hemotoxic
damaging or destructive to blood cells
Pulmonotoxic
damaging or destructive to lungs
Give an example of how culture affects the behavior of an individual or organization. Explain.
McAllen vs El Paso; The hospitals in McAllen thought treated patients as profit centers (by ordering excessive and unnecessary tests), while El Paso had a focus on the patient as people.
conformity bias
caused by group peer pressure
Beauty bias
think the most physically attractive person will be the most successful
similarity bias
tendency to like people who are similar to us
halo effect
tendency to see one great thing about a person, which affects our opinion of everything else about them
horns effect
tendency to see one ‘bad’ thing about a person and it affects our opinion of everything else about them.
Explain the difference between FAR and fatality rate.
While FAR is based on employee working hours, fatality rate is independent of hours worked. Fatality rate does not account for time on task
Give an example of a design change which had unintended consequences
Flixborough, England: Removal and bypass of reactor 5. No safety review was performed and the change was of substandard design, resulting in an explosion
What is a spirometer? What does it measure?
Device that measure lung capacity of lungs: total volume exhaled (FVC, L); forced expired volume measured at 1 second (FEV1, L/s); forced expiratory flow in the middle range of the vital capacity (FEV 25-75%, L/s); the ratio of the observed FEV1 to FVC*100 (FEV1/FVC%)
What dust size particle range is typically considered as most potentially harmful to the lungs?
0.2 – 5 microns.
What does PPE stand for? Give two examples of PPE
Personal protective equipment; hard hat, fire-rated shirt
Be able to fill in the NFPA diamond (which rating goes in which area, ranges of rankings, etc.)
LEFT: Health; TOP: Fire; RIGHT: Stability; Bottom: Specific Hazard
What are the four categories of inherently safer design techniques? Give brief descriptions of each.
MINIMIZATION: reducing the hazards by using smaller quantities of hazardous substances
SUBSTITUTION: safer materials should be used in place of hazardous ones.
MODERATION: using hazardous materials under less hazardous conditions (lowering temp to lower Psat)
SIMPLIFICATION: error tolerance – simpler plants provide fewer opportunities for error
Flixborough, England
installing the bypass line without a safety review or adequate supervision by experienced engineering personnel; holding excessive amounts of flammable material in close proximity
Bhopal, India
best ways to prevent a hazardous release is to engineer around it. Instead of using the reaction pathway that included the dangerous MIC intermediate
Seveso, Italy
TCDD released; civilians were not notified until several days later; proper procedure not followed
What do the categories ED, TD, and LD represent? What does LD50 mean?
ED: effective dose; response to chemical or agent is minor and reversible
TD: response to agent is toxic (not lethal, but irreversible, e.g. liver damage)
LD50 – dose that results in the death of 50% of the population
What are the four pathways by which toxicants typically enter biological organisms? Which pathways are typically the fastest? Which pathways are considered most important in an industrial setting?
Inhalation^, injection, absorption^, ingestion
Fastest*; Industrial importance^
Pasadena, Texas
It is important to perform PHAs on a regular basis. This can reveal sub-standard valving arrangements such as the one in the Pasadena plant
Texas City, Texas
overfilled tower caused hydrocarbons release; should performed a root cause analysis to prevent the last three near-misses, the contractor trailers would have never been allowed into the unsafe areas, and the ISOM unit would not have been started up before the existing problems were resolved
port wentworth, georgia
poor houscleaning; company failed to correct ongoing and known hazardous conditions; sugar dust explosion
jacksonville, Fl
Cooling line failed; importance of design redundancy in a cooling system cannot be understated, especially if explosions can occur within 10 minutes of failure; single- point failures should be eliminated when designing processes.
What does TLV mean? What are the different categories of TLV? Explain what each category
threshold limit value;
TLV-TWA: time-weighted average; 8hr/day; conc employees can be exposed to w/ no adverse effects
TLV-STEL: short-term exposure limit; 15min; conc employees can be exposed to w/o irritation, tissue damage, etc
TLC-C: ceiling: conc. that should never be exceeded; no duration
What does PEL stand for? What organization uses the PEL standard? PEL values are closely related to one of the TLV categories; which one?
permissible exposure level; defined by OSHA; closely relates to TLV-TWA
What are three common leading indicators of “best practices” related to process safety? When were these first published?
Regular, documented inspections of safety critical items (with follow up action items);
Documentation of keeping up with PHA/safety audit action items;
Number of demands on safety systems; “near misses”
SEPT 2014
What does IDLH mean? What exposure time period is associated with IDLH? What exposure responses are used to determine the IDLH concentrations?
immediately dangerous to life or health; 30min; without acute toxicity reactions (severe eye irritation);
What does ERPG stand for? What are the three levels of ERPG and how are they defined (time and exposure response)?
Emergency response planning guidelines;
max concentration one can be exposed to…
1 - w/ almost all only mild, transient effects
2 - w/o irreversible effects
3 - w/o life threatening effects
Explain what is meant by a causative variable. Explain how a probit is typically related to the response of some causative variable.
Causative factor represents dose of damaging agent; probit related to the causative variable by transforming the sigmoid shape of the normal response curve (for population for specified effect) into a straight line.
what are the five fundamental cannons of the AIChE Code of Professional Ethics relevant to process safety?
1) safety is paramount
2) one must only speak in objective truth
3) only perform in areas of competence
4) avoid conflicts of interests
5) follow ethical and professional responsibilities
what are the four pillars of Risk Based Process Safety? Briefly explain each.
1) COMMITMENT TO PROCESS RISK
safety culture is paramount
2) UNDERSTANDING PROCESS RISK
involves understanding chemistries and investigating potential hazards in plant design
3) MANAGING RISK
continuous performance of process hazard analysis and improvement of processes via MOC
4) LEARNING FROM PAST EXPERIENCE
includes learning from mistakes of other plants as well as the investigation and documentation of near-misses and performing of root-cause investigations
