environmentally conscious design & manufacturing

Environmentally Conscious Design & Manufacturing (ME592)

Date: March 10, 2000 Slide:1

Environmentally Conscious Design & Manufacturing

Class 3: Hazard Assessment

Prof. S. M. Pandit



Hazard Assessment

Agenda– Hazard Evaluation– Case study - Hazards and risks in Manufacturing– Stages of Hazard Identification and Risk Evaluation– Assessment Tools:

• Product• Process• Facility



Types of Hazards

Other hazards:

Civil Disturbances, Geological Events

Epidemics, Infestation

Fires, Meteorological,

Hydrological hazards

Technological hazards– Chemical Spills – Structural failure – Gas Explosions, Leaks – Oil Spills – Radiological, Nuclear

Ref: http://life.csu.edu.au/hazards/topics.html



Structural failure hazard assessment

Hazard Evaluation - 1

Getting data– Surveys, Designed experiments, Modeling and

simulation



Hazard Evaluation - 2

Assign scores to factors / sub-factors

Estimate relation between score & variables

Compare alternatives



Case Study

Waste Stream Hazards (Process related), also, Product related & facility related

Product Manufacturing Activity

Waste Streams

Fuel combustion

EnergyChipsCutting Fluids

SulphurNitrogenCarbon MonoxideCarbon particlesDust

Energy

HeatWater contaminationMist generationAcid RainAir Toxins

Environmental hazards



Solids Liquids GasesAerosolsEnergy

Hazard Scoring

Machining Wastes

Solids(Chips)

Liquids(Cutting Fluid)

Gases(Effluent gases)

Aerosols(Mist)

Energy (Heat)

Hazard Scoring

Environmental hazardRiskAssessment

Hazard & Risk



Risk Space

Observable- Oil well Explosion

Not Observable- CO concentration rise

Controllable- Manufacturing process parameters

Uncontrollable- Nature

• Risk: The probability of “suffering harm” from a product• Twin dimensions: Contaminant concentration, Duration of exposure



Risk - 1

Risk

Biological System Damage

Aesthetic Degradation

Damage to Planetary Systems

Product

Process

Facility



Risk - 2

Risk Assessment:

•Hazard Identification

•“Dose” Evaluation

•Probability of undesirable impact due to “dose”

•Exposure determination

RISK MANAGEMENT



Risk - 3

1 Log Probit model

2 Multistage model

1 P(d) = log10 d)

2 P(d) = 1 - e-[+ d+ +d2+ ... + rd

r]



Risk - 4

Multi stage model

“r” is the number of stages through which the

hazard is propagated, and ’s are constant

weighting factors. These are relatively easy to

visualize, although the weighting factors have a

strong influence on the calculated “risk.”



Risk-5



Risk-6

Exposure Determination

Risk Impact

I=N P(d)

where N is the number of exposed people



Risk - 7

Log - Probit modeling and analysis is discussed

comprehensively by Charles Annis at

http://www.statisticalengineering.com/index.html.

It uses Generalized Linear Modeling (GLC) where

the binary nature of the hazard (either there or not

there) is taken into account. An application to

fracture cracks is discussed.



Risk - 8

Radiation Risks

{Obtained by

multiplying by

appropriate

carcinogenic

factors for various

modes of exposure

http://omega.lbl.gov/select/risk.htm



Risk - 9

Example:

Radiation risk due to

ingestion, inhalation

and dermal exposure

summed and plotted

for individual with

assumed lifetime and

exposure duration



Risk - 10

Comparison of

alternatives



Risk - 11



Assessment Tools - 1

Life Cycle Assessment: (Goal - Understand & Improve)

Inventory AnalysisImpact AnalysisImprovement Analysis

Assessment ToolsProductProcessFacility




Environmentally Responsible Product Matrix

Environmental Concern

Life - Cycle Stage M{stage(i),concern(j)}




The sum of all the elements, which provides

an indication of the “Product Rating.”

Matrix elements are estimated on the basis

of underlying checklists and protocols, and

assume a value between 0 and 1.

REPRT=ijMi,j




Target Plots(From Env. Resp.Prod. matrix)

1,1




Environmentally responsible process matrix - similar analysis. (Life cycle stage / Environmental concern)

Environmentally Responsible facility matrix:Facility activity (site selection, maintenance)vsEnvironmental Concern



Homework #1

The following problems are out of the textbook “Industrial Ecology”1. Problem 1.1 (Answer: 0.9)2. Problem 1.2 (Answer: 3.77million)3. Problem 1.3 (Answer: 3.924 million)4. Problem 1.4 Answer:Country Eco2(Pg/yr) GNP/capita Eco2/dollar of GNP(103g)

Brazil 0.53 2950 1.22China 1.22 370 2.91India 0.56 310 2.13Nigeria 0.15 260 0.573United States 2.38 21,000 0.458

environmentally conscious design & manufacturing

Documents