ASTM F1780-97(2018)
(Guide)Standard Guide for Estimating Oil Spill Recovery System Effectiveness
Standard Guide for Estimating Oil Spill Recovery System Effectiveness
ABSTRACT
This guide covers the key factors to consider in estimating the effectiveness of containment and recovery systems that may be used to assist in the control of oil spills on water. The purpose of this guide is to provide the user with information on assessing the effective use of spill-cleanup equipment. It is intended for use by those involved in planning for and responding to oil spills. In evaluating the effectiveness of containment and recovery systems used in response to oil spills, many factors need to be considered of which skimmer performance is but one. The objective of this guide is to describe a range of factors that must be considered in estimating recovery system effectiveness. Response strategies will depend to some extent on the type of spill. The spill scenario should be defined as to whether it is an instantaneous or continuous release, whether or not the spill has ceased flowing, and whether the spill is contained or uncontained. The following oil slick properties must be specified for the spill scenario: spill volume; area; slick thickness; slick viscosity; and emulsification.
SCOPE
1.1 This guide covers the key factors to consider in estimating the effectiveness of containment and recovery systems that may be used to assist in the control of oil spills on water.
1.2 The purpose of this guide is to provide the user with information on assessing the effective use of spill-cleanup equipment. It is intended for use by those involved in planning for and responding to oil spills.
1.3 Sections of this guide describe calculation procedures for estimating recovery system effectiveness. It should be understood that any such calculations cannot be expected to predict system performance, but are intended to provide a common basis for comparing system performance.
1.4 One of the main reasons that the calculation procedures cannot be used to predict system performance is that the analysis is sensitive to assumptions made on the properties of the oil slick, and particularly the changes in slick thickness and emulsification. It is emphasized that the purpose of this guide is not to provide a standard method for estimating slick property changes, but rather to provide a standard guide for using that information in comparing system performance.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Buy Standard
Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F1780 − 97 (Reapproved 2018)
Standard Guide for
Estimating Oil Spill Recovery System Effectiveness
This standard is issued under the fixed designation F1780; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
2.1 ASTM Standards:
1.1 This guide covers the key factors to consider in estimat-
F625PracticeforClassifyingWaterBodiesforSpillControl
ing the effectiveness of containment and recovery systems that
Systems
may be used to assist in the control of oil spills on water.
F631Guide for Collecting Skimmer Performance Data in
1.2 The purpose of this guide is to provide the user with
Controlled Environments
information on assessing the effective use of spill-cleanup
F808Guide for Collecting Skimmer Performance Data in
equipment. It is intended for use by those involved in planning
Uncontrolled Environments (Withdrawn 1997)
for and responding to oil spills.
F1523Guide for Selection of Booms in Accordance With
Water Body Classifications
1.3 Sections of this guide describe calculation procedures
for estimating recovery system effectiveness. It should be
3. Terminology
understood that any such calculations cannot be expected to
3.1 Definitions:
predict system performance, but are intended to provide a
3.1.1 advancing skimmer, n—a skimmer that is designed to
common basis for comparing system performance.
be used to sweep out the spill area.
1.4 One of the main reasons that the calculation procedures
3.1.1.1 Discussion—The skimmer may be independent or
cannot be used to predict system performance is that the
maybeattachedtocontainmentboomtoincreasesweepwidth.
analysis is sensitive to assumptions made on the properties of
In some cases, the skimmer may not be attached to the boom
theoilslick,andparticularlythechangesinslickthicknessand
but is positioned in the pocket of the boom for skimming. As
emulsification. It is emphasized that the purpose of this guide
long as the skimmer operates while moving, it is considered to
is not to provide a standard method for estimating slick
be an advancing skimmer. Some skimmers are used in both an
property changes, but rather to provide a standard guide for
advancing and stationary mode. These are classified according
using that information in comparing system performance.
to their application.
1.5 The values stated in SI units are to be regarded as
3.1.2 contained spills, n—a spill that is restricted from
standard. No other units of measurement are included in this
spreading by containment boom or natural means.
standard.
3.1.3 oil slick encounter rate, n—the volume of oil slick per
unittimeactivelyencounteredbytheoilspillrecoverysystem,
1.6 This international standard was developed in accor-
and therefore available for containment and recovery (m /h).
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
3.1.4 oil spill recovery system, n—a combination of devices
Development of International Standards, Guides and Recom-
that operate together to recover spilled oil; the system would
mendations issued by the World Trade Organization Technical
include some or all of the following components: (1) contain-
Barriers to Trade (TBT) Committee.
ment boom, (2) skimmer, (3) support vessels to deploy and
operate the boom and skimmer, (4) discharge/transfer pumps,
(5) oil/water separator, (6) temporary storage devices, and (7)
shore based storage/disposal.
1 2
This guide is under the jurisdiction of ASTM Committee F20 on Hazardous For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Substances and Oil Spill Responseand is the direct responsibility of Subcommittee contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
F20.12 on Removal. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Sept. 1, 2018. Published September 2018. Originally the ASTM website.
approved in 1997. Last previous edition approved in 2010 as F1780–97 (2010). The last approved version of this historical standard is referenced on
DOI: 10.1520/F1780-97R18. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1780 − 97 (2018)
3.1.5 recovery system effectiveness, n—the volume of oil it is an instantaneous or continuous release, whether or not the
that is removed from the environment by a given recovery spill has ceased flowing, and whether the spill is contained or
system in a given recovery period. uncontained.
3.1.6 recovery period, n—the time available for recovery
5.2 Oil Slick Properties—The following oil slick properties
systems to carry out cleanup operations. must be specified for the spill scenario. As some of these
properties may vary with time, it may be desirable to use
3.1.7 response time, n—the time interval between the spill
computer-based behavior models to produce spill property
incident and the start of cleanup operations.
information for the time period of interest. For certain appli-
3.1.8 stationary skimmer, n—a skimmer that is intended to
cations it may be useful to produce standard sets of spill
be used in a fixed location and is moved to new accumulations
property information that describe spills of interest as a
of oil as skimming progresses.
function of time.
3.1.8.1 Discussion—Somestationaryskimmersareusedina
5.2.1 Spill Volume—The total volume of oil spilled should
containment boom system that moves to collect oil, then 3
be specified (m ). For spills that have not ceased, a spill rate
pausestopermittheskimmertorecovertheoilcollected.Even 3
(m /h) should also be specified.
though this system moves periodically, the skimmer is still
5.2.2 Spill Area—The total spill area must be estimated in
ranked as a stationary skimmer because it operates when the
order to calculate estimates of slick thickness. For uncontained
system is at rest.
spills, the total spill area will increase over time; estimates can
3.1.9 uncontained spill, n—a spill that continues to spread bemadeusingcomputer-basedbehaviormodels.Alternatively,
after the recovery effort begins.
a simplified spreading model (Fig. 1: example spreading
curves) can be used for first-order estimates.
4. Summary of Guide 5.2.3 Slick Thickness—Slickthicknessisusedinsubsequent
calculations of system encounter rate. Slick thickness is de-
4.1 In evaluating the effectiveness of containment and
fined as the overall average thickness of the slick, and is
recovery systems used in response to oil spills, many factors
estimated by dividing the spill volume by the total spill area at
need to be considered of which skimmer performance is but
any given time. For this calculation, spill volume should take
one.Theobjectiveofthisguideistodescribearangeoffactors
into account losses from the slick due to evaporation and
that must be considered in estimating recovery system effec-
natural dispersion, and increases to the slick volume due to
tiveness.
emulsification.Foruncontainedspills,naturalspreadingforces
4.2 In order to evaluate a recovery system, there are two
will cause the slick thickness to decline steadily during
general types of information required, a set of information to
recovery operations, and may result in a discontinuous slick
describe the spill scenario against which the system will be
composed of windows and patches separated by sheen or open
measured,andasetofinformationtodescribetheperformance
water, or both. These factors should be considered in estimat-
characteristics of the recovery system.
ing an overall average slick thickness.
5.2.4 Slick Viscosity—The viscosity of the spilled product is
4.3 Information on the spill is required to adequately define
used as a criteria to evaluate skimmer performance, as many
the problem and thereby provide a focus for the evaluation
skimming and pumping units will perform less effectively as
process. The spill should be defined in sufficient detail as to
viscosity increases. The viscosity of the spilled product will
allowanunambiguousinterpretationofitsbehaviorintermsof
generally increase through the recovery period as the oil is
the operating parameters of the countermeasures system. For
subjected to weathering and emulsification processes. The
certain purposes it may be desirable to develop a set of
viscosity should be specified as mm /s (cSt).
standard spill scenarios against which response system effec-
tiveness would be measured in a quantifiable manner.
4.4 The performance characteristics must be identified for
therecoverysystemanditsvariouscomponents.Ingeneral,the
informationrequirementswillincludetheratesorcapacities,or
both, the operating limitations, and the support requirements.
4.5 This guide covers equipment-related factors that will
affect recovery-system effectiveness.Additional important fac-
tors that are not covered in this guide but should be considered
as being critical to the success of a spill response include:
contingency planning; communications plans; government ap-
provals; logistics of supporting manpower and equipment in
the field; and training and exercising of manpower.
5. Spill-related Information
5.1 Spill Type:
5.1.1 Response strategies will depend to some extent on the
typeofspill.Thespillscenarioshouldbedefinedastowhether FIG. 1 Total Slick Area versus Time
F1780 − 97 (2018)
5.2.5 Emulsification—Emulsification is important as a spill 5.3.4 Visibility—Duetoconcernswithworkersafetyinpoor
process not only for its effect on oil viscosity but also because visibility,aswellastheinefficienciesrelatedtothemonitoring,
an emulsified oil represents a greater total volume of spill tracking, and containment of oil slicks during periods of poor
product that must be handled by skimming and pumping visibility, it is assumed in general that recovery operations are
systems. Many crude oils and refined products will tend to only possible when there is daylight and visibility of greater
emulsify over the life of the spill depending on the properties than 500 m (0.25 n.miles). Both of these factors should be
oftheoilandthelevelofwaveenergyinthespillenvironment. expressed as the percentage of time that conditions exist that
The degree of emulsification should be specified as the would allow effective operations.
emulsified water content expressed as a percentage.
5.3.4.1 It may be possible to effectively operate during
5.2.5.1 It is recognized that emulsification rates for oil
periods of darkness and poor visibility if the recovery system
spilled in the marine environment will vary greatly depending
includes adequate lighting equipment, remote sensing systems
ontheoilproperties,spillsize,seaconditions,andtemperature.
for assisting monitoring and containment efforts, or highly
As noted in 1.4, it is not the intent of this guide to provide
accurate navigation systems, or combination thereof.This may
standardratesofemulsificationforavarietyofoilproductsand
be particularly applicable to spills in nearshore and protected
environmental conditions. For the purposes of comparing
waters. In such cases a more liberal criteria for visibility
system performance, the data in Table 1 is provided as an
limitations could be specified.
example of emulsification data for crude oil over a period of
5.3.5 Summary of Environmental Applicability Factors—
several days. Users of this guide are encouraged to use
The wave exceedance, daylight, and visibility factors can be
alternative data that suits their particular oils and environmen-
combined to produce an overall applicability factor that would
tal conditions.
represent the percentage of time that a given recovery system
could be effectively used for a given spill scenario. For
5.3 Spill Environment:
example, for an environment that has waves less than 2 m for
5.3.1 Temperature—Water temperature is important as a
80% of the time, receives 14 h of daylight, and has visibility
parameter for estimating oil slick properties as well as the rate
greater than 500 m for 95% of the time (note: all figures
of change of those properties due to weathering and emulsifi-
should be specified for the time of year of interest), the
cation.(Itisassumedthatthetemperatureoftheoilslickisthe
environmental applicability would be estimated as:
same as the water on which the oil is floating.) Water
(0.80)×(14⁄24)×(0.95)=44%.
temperature is defined as the temperature of the upper surface
layer and should be specified as °C.
5.4 Spill Location:
5.3.1.1 Airtemperaturemaybeimportantasaparameterfor
5.4.1 Spill location should be specified with respect to
modifying or limiting the performance of skimming and
distanceofresponsebases,inordertoestimatetransittimesfor
pumping equipment, and should be specified as °C.
the recovery systems, and with respect to shoreline, in order to
5.3.2 Wind/Waves—The wind and wave environment is
estimate the time available to respond prior to shoreline oiling.
important to the analysis for two reasons; first, as a parameter
Spill location may also be of importance when evaluating
in estimating the behavior changes of the oil slick, and second,
recovery systems that include the shuttling of recovered oil
as a limiting factor for recovery operations. For the first
between the recovery site and temporary storage locations, in
purpose, average wind speeds (km/h) should be specified. For
which case transit times may have to be deducted from the
the purpose of establishing criteria for limiting recovery
on-site availability of storage systems.
operations, exceedance statistics (significant wave height)
should be specified for the spill location. Exceedance criteria
6. Recovery System Information
should be expressed as the percentage of time that conditions
willallowrecoveryoperationswithreferencetotheequipment 6.1 Containment System Operating Factors:
selected for the response and the environmental criteria listed
6.1.1 Encounter Rate—The encounter rate of the recovery
in Practice F625. For example, for spills in open water, wave
systemisaprimeconsiderationinevaluatingperformance.The
exceedance data should be specified as the percentage of time
encounter rate is simply the rate (m /h) at which the system
thatwavesarelessthanorequalto2m,whichwouldrepresent
encounters the oil slick. The encounter rate includes three
the percentage of time that equipment specified for open water
components: sweep width, encounter speed, and oil slick
use would be applicable.
thickness.
5.3.3 Current—The presence of water currents may i
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F1780 − 97 (Reapproved 2010) F1780 − 97 (Reapproved 2018)
Standard Guide for
Estimating Oil Spill Recovery System Effectiveness
This standard is issued under the fixed designation F1780; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This guide covers the key factors to consider in estimating the effectiveness of containment and recovery systems that may
be used to assist in the control of oil spills on water.
1.2 The purpose of this guide is to provide the user with information on assessing the effective use of spill-cleanup equipment.
It is intended for use by those involved in planning for and responding to oil spills.
1.3 Sections of this guide describe calculation procedures for estimating recovery system effectiveness. It should be understood
that any such calculations cannot be expected to predict system performance, but are intended to provide a common basis for
comparing system performance.
1.4 One of the main reasons that the calculation procedures cannot be used to predict system performance is that the analysis
is sensitive to assumptions made on the properties of the oil slick, and particularly the changes in slick thickness and emulsification.
It is emphasized that the purpose of this guide is not to provide a standard method for estimating slick property changes, but rather
to provide a standard guide for using that information in comparing system performance.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
F625 Practice for Classifying Water Bodies for Spill Control Systems
F631 Guide for Collecting Skimmer Performance Data in Controlled Environments
F808 Guide for Collecting Skimmer Performance Data in Uncontrolled Environments (Withdrawn 1997)
F1523 Guide for Selection of Booms in Accordance With Water Body Classifications
3. Terminology
3.1 Definitions:
3.1.1 advancing skimmer, n—a skimmer that is designed to be used to sweep out the spill area.
3.1.1.1 Discussion—
heThe skimmer may be independent or may be attached to containment boom to increase sweep width. In some cases, the skimmer
may not be attached to the boom but is positioned in the pocket of the boom for skimming. As long as the skimmer operates while
moving, it is considered to be an advancing skimmer. Some skimmers are used in both an advancing and stationary mode. These
are classified according to their application.
3.1.2 contained spills, n—a spill that is restricted from spreading by containment boom or natural means.
This guide is under the jurisdiction of ASTM Committee F20 on Hazardous Substances and Oil Spill Responseand is the direct responsibility of Subcommittee F20.12
on Removal.
Current edition approved June 1, 2010Sept. 1, 2018. Published July 2010September 2018. Originally approved in 1997. Last previous edition approved in 20022010 as
F1780 – 97 (2002).(2010). DOI: 10.1520/F1780-97R10.10.1520/F1780-97R18.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F1780 − 97 (2018)
3.1.3 oil slick encounter rate, n—the volume of oil slick per unit time actively encountered by the oil spill recovery system, and
therefore available for containment and recovery (m /h).
3.1.4 oil spill recovery system, n—a combination of devices that operate together to recover spilled oil; the system would include
some or all of the following components: (1) containment boom, (2) skimmer, (3) support vessels to deploy and operate the boom
and skimmer, (4) discharge/transfer pumps, (5) oil/water separator, (6) temporary storage devices, and (7) shore based
storage/disposal.
3.1.5 recovery system effectiveness, n—the volume of oil that is removed from the environment by a given recovery system in
a given recovery period.
3.1.6 recovery period, n—the time available for recovery systems to carry out cleanup operations.
3.1.7 response time, n—the time interval between the spill incident and the start of cleanup operations.
3.1.8 stationary skimmer, n—a skimmer that is intended to be used in a fixed location and is moved to new accumulations of
oil as skimming progresses.
3.1.8.1 Discussion—
Some stationary skimmers are used in a containment boom system that moves to collect oil, then pauses to permit the skimmer
to recover the oil collected. Even though this system moves periodically, the skimmer is still ranked as a stationary skimmer
because it operates when the system is at rest.
3.1.9 uncontained spill, n—a spill that continues to spread after the recovery effort begins.
4. Summary of Guide
4.1 In evaluating the effectiveness of containment and recovery systems used in response to oil spills, many factors need to be
considered of which skimmer performance is but one. The objective of this guide is to describe a range of factors that must be
considered in estimating recovery system effectiveness.
4.2 In order to evaluate a recovery system, there are two general types of information required, a set of information to describe
the spill scenario against which the system will be measured, and a set of information to describe the performance characteristics
of the recovery system.
4.3 Information on the spill is required to adequately define the problem and thereby provide a focus for the evaluation process.
The spill should be defined in sufficient detail as to allow an unambiguous interpretation of its behavior in terms of the operating
parameters of the countermeasures system. For certain purposes it may be desirable to develop a set of standard spill scenarios
against which response system effectiveness would be measured in a quantifiable manner.
4.4 The performance characteristics must be identified for the recovery system and its various components. In general, the
information requirements will include the rates or capacities, or both, the operating limitations, and the support requirements.
4.5 This guide covers equipment-related factors that will affect recovery-system effectiveness. Additional important factors that
are not covered in this guide but should be considered as being critical to the success of a spill response include: contingency
planning; communications plans; government approvals; logistics of supporting manpower and equipment in the field; and training
and exercising of manpower.
5. Spill-related Information
5.1 Spill Type:
5.1.1 Response strategies will depend to some extent on the type of spill. The spill scenario should be defined as to whether
it is an instantaneous or continuous release, whether or not the spill has ceased flowing, and whether the spill is contained or
uncontained.
5.2 Oil Slick Properties—The following oil slick properties must be specified for the spill scenario. As some of these properties
may vary with time, it may be desirable to use computer-based behavior models to produce spill property information for the time
period of interest. For certain applications it may be useful to produce standard sets of spill property information that describe spills
of interest as a function of time.
3 3
5.2.1 Spill Volume—The total volume of oil spilled should be specified (m ). For spills that have not ceased, a spill rate (m /h)
should also be specified.
5.2.2 Spill Area—The total spill area must be estimated in order to calculate estimates of slick thickness. For uncontained spills,
the total spill area will increase over time; estimates can be made using computer-based behavior models. Alternatively, a
simplified spreading model (Fig. 1: example spreading curves) can be used for first-order estimates.
5.2.3 Slick Thickness—Slick thickness is used in subsequent calculations of system encounter rate. Slick thickness is defined as
the overall average thickness of the slick, and is estimated by dividing the spill volume by the total spill area at any given time.
For this calculation, spill volume should take into account losses from the slick due to evaporation and natural dispersion, and
F1780 − 97 (2018)
FIG. 1 Total Slick Area versus Time
increases to the slick volume due to emulsification. For uncontained spills, natural spreading forces will cause the slick thickness
to decline steadily during recovery operations, and may result in a discontinuous slick composed of windows and patches separated
by sheen or open water, or both. These factors should be considered in estimating an overall average slick thickness.
5.2.4 Slick Viscosity—The viscosity of the spilled product is used as a criteria to evaluate skimmer performance, as many
skimming and pumping units will perform less effectively as viscosity increases. The viscosity of the spilled product will generally
increase through the recovery period as the oil is subjected to weathering and emulsification processes. The viscosity should be
specified as mm /s (cSt).
5.2.5 Emulsification—Emulsification is important as a spill process not only for its effect on oil viscosity but also because an
emulsified oil represents a greater total volume of spill product that must be handled by skimming and pumping systems. Many
crude oils and refined products will tend to emulsify over the life of the spill depending on the properties of the oil and the level
of wave energy in the spill environment. The degree of emulsification should be specified as the emulsified water content expressed
as a percentage.
5.2.5.1 It is recognized that emulsification rates for oil spilled in the marine environment will vary greatly depending on the oil
properties, spill size, sea conditions, and temperature. As noted in 1.4, it is not the intent of this guide to provide standard rates
of emulsification for a variety of oil products and environmental conditions. For the purposes of comparing system performance,
the data in Table 1 is provided as an example of emulsification data for crude oil over a period of several days. Users of this guide
are encouraged to use alternative data that suits their particular oils and environmental conditions.
5.3 Spill Environment:
5.3.1 Temperature—Water temperature is important as a parameter for estimating oil slick properties as well as the rate of
change of those properties due to weathering and emulsification. (It is assumed that the temperature of the oil slick is the same
as the water on which the oil is floating.) Water temperature is defined as the temperature of the upper surface layer and should
be specified as °C.
5.3.1.1 Air temperature may be important as a parameter for modifying or limiting the performance of skimming and pumping
equipment, and should be specified as °C.
5.3.2 Wind/Waves—The wind and wave environment is important to the analysis for two reasons; first, as a parameter in
estimating the behavior changes of the oil slick, and second, as a limiting factor for recovery operations. For the first purpose,
average wind speeds (km/h) should be specified. For the purpose of establishing criteria for limiting recovery operations,
exceedance statistics (significant wave height) should be specified for the spill location. Exceedance criteria should be expressed
as the percentage of time that conditions will allow recovery operations with reference to the equipment selected for the response
and the environmental criteria listed in Practice F625. For example, for spills in open water, wave exceedance data should be
specified as the percentage of time that waves are less than or equal to 2 m, which would represent the percentage of time that
equipment specified for open water use would be applicable.
5.3.3 Current—The presence of water currents may influence the selection of response strategies for a spill scenario, and may
lead to a reduction in containment effectiveness in certain applications. The water currents, in m/s, should be specified for a given
environment, with due regard to any local variations.
TABLE 1 Example Data for Emulsified Water Content versus
Time for Crude Oil
12 h 1 day 2 days 3 days
% Water Content 30 50 65 75
F1780 − 97 (2018)
5.3.4 Visibility—Due to concerns with worker safety in poor visibility, as well as the inefficiencies related to the monitoring,
tracking, and containment of oil slicks during periods of poor visibility, it is assumed in general that recovery operations are only
possible when there is daylight and visibility of greater than 500 m (0.25 n.miles). Both of these factors should be expressed as
the percentage of time that conditions exist that would allow effective operations.
5.3.4.1 It may be possible to effectively operate during periods of darkness and poor visibility if the recovery system includes
adequate lighting equipment, remote sensing systems for assisting monitoring and containment efforts, or highly accurate
navigation systems, or combination thereof. This may be particularly applicable to spills in nearshore and protected waters. In such
cases a more liberal criteria for visibility limitations could be specified.
5.3.5 Summary of Environmental Applicability Factors—The wave exceedance, daylight, and visibility factors can be combined
to produce an overall applicability factor that would represent the percentage of time that a given recovery system could be
effectively used for a given spill scenario. For example, for an environment that has waves less than 2 m for 80 % of the time,
receives 14 h of daylight, and has visibility greater than 500 m for 95 % of the time (note: all figures should be specified for t
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.