Crew Habitability: What You Need to Know

Crew Habitability: What You

Need to Know

Dr. Kevin McSweeney

Manager - Human Factors Department

ABS, Corporate Technology, Houston Texas

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What is Habitability?

• The acceptability of a vessel (or facility) as determined by its physical arrangements, as well as the ambient environmental qualities of vibration, noise, indoor climate, and lighting

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Why Habitability?

• Proper facility design and ambient environmental conditions are influential factors for enhancing human performance and reducing human error

• Ambient environment conditions where the crew work, sleep, eat, rest and relax can influence overall sense of comfort (habitability), well-being and perhaps crew recruiting and retention

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Guide for Crew Habitability on Ships

• Crew Habitability– Basic notation (HAB)

aimed at supporting task performance

– Higher notation (HAB+) aimed at enhancing crew habitability

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Guide Contents

Crew Habitability

Accommodations Design

Checklists for Various Spaces

Compliance Criteria& Measurement Methods

Ambient Environmental

Qualities

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Accommodations Design

• Access/egress• Berthing• Sanitary spaces• Offices• Food services• Recreational

facilities • Laundry• Medical spaces

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Ambient Environment

• Human Whole-

Body Vibration

• Noise

• Indoor Climate

• Lighting

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Human Whole-Body Vibration

• Criteria included for:– Crew task performance– Enhanced habitability

• Basis of measurement methodology:– BS 6841

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Vibration Frequencies of Interest

• 0.5 Hz to 25 Hz

– Motion induce instability (MII) modest discomfort and fatigue

– Internal body parts resonate

• 25 Hz to 80 Hz– Performance degradation due

to decay in sensations and perceptions

z-axis

y-axis

x-axis

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Interference with Crew Activities

• Vibration Frequency range (Hz)– Reading (instruments) 0.5 - 12

– Reading (text) 0.5 - 50

– Control manipulation 0.5 - 30

– Speech 1 - 20

– Depth perception 25 - 40

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Noise

• Criteria based on:– Normal activities in a

space– Frequency of occupation

of a space– Communications needs– Crew’s expectations

• Basis of measurement methodology: – ISO 2923

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Noise Levels

• Adverse / improper levels can:– Cause speech interference

– Interfere with concentration and thought processes

– Disrupt sleep

– Cause fatigue and aggression

• Appropriate noise levels can:– Provide an environment for improved human

performance

– Have a positive psychological effect on people

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Big Contributor – HVAC Noise

• Potential Solutions:– Configurations including largest feasible duct

diameter, gradual turns– Use of HVAC

silencers / resonators– Tuning of resonators

to the blade frequency– Reduction of pressure

changes– Proper Supports for

Exhaust and Piping Systems– Secure ventilation ductwork piping systems will

reduce vibration against shipboard structures

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Indoor Climate

• Criteria based on human performance data

• Basis of measurement methodology :

– ANSI / ASHRAE 55a

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What Determines Comfort?

• Environmental factors– Air temperature– Air speed– Humidity

• Individual factors– Activity– Clothing insulation

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Lighting

• Criteria based on supporting tasks via general and activitylighting

• Basis of measurement methodology:

– IESNA RP-12

– ISO 8995

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Lighting Requirements

• Relationship between age and lightrequired for readinggood print

Source: Phillips Lighting

Ligh

t R

equi

rem

ent

(x 1

00 L

ux)

~ 3x greater

~7x greater

Age (years)

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Lighting

Visual performance vs. Light level (in Lux) for an assembly task

Young

Older

Source: Phillips Lighting

~7x greater

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HAB and HAB+ Notation HAB and HAB+ Notation

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Habitability Data Gathering

• Data collection efforts started in 2001 and continues today

• Data has been obtained from multiple sources:– Offshore installations– Commercial ships– Workboats

(OSV’s and crew boats)– Passenger vessels

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Data Gathering

• Data from Pacific, Europe, and Americas

• Review of accommodations design and layout

• Focus on ambient environment characteristics (noise and vibration)

• Informal (but informative) interviews with crew members

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Questions?

Dr. Kevin McSweeneykmcsweeney@eagle.org

281-877-5965