# Presentation: 403157

## How High Is the Layout?How Deep Are the Scenes?

*Applying Basic Ergonomics to Model Railroad Design  *
*By Les Dahlstedt *

## Not that discussion again!(a disclaimer)

- While it’s true that the matter of layout height
- has gotten attention and  printers’ ink during the
- past 60 years, a comprehensive analysis that
- includes statistics on the human element
- appears to be greenfield territory.
- Hopefully...this will be something you haven’t
- seen before...

## Introduction

*Why the subject draws attention*

## We’ve done it at least once:

- Made some portion of the layout too low or too high.
- Made some of the scenes too deep.
- Made the ‘below-decks’ space uncomfortably low, cluttered with support members and painful to work in.
- Built a multi-level layout that made upper level access for maintenance a pain in the neck (or back).

## ...and thus

- Some builders and their operators will have difficulty because the layout is too high or low.
- Some scenes will be too deep to work on and maintain.
- And you _will_ despise having to get under the layout to work.
*...**.please don’t ask me how I know this stuff*

## Ergonomics & Model Railroad Design

## What is Ergonomics?

- According to the CDC...
*Ergonomics is a discipline that involves*
*arranging the environment to fit the person in it.*
*When ergonomics is applied correctly in the*
*work environment, visual and musculoskeletal*
*discomfort and fatigue are reduced*
*significantly.*

## Why Ergonomics?

- Manufacturers and the insurance industry have long recognized the importance to modify workers’ surroundings to minimize the potential for workplace injury and fatigue. More attention is being paid to chair and desk heights, the design of human interface to manufacturing equipment and to office machines.
- We now see ergonomic design used in automobiles, home furnishings, commercial aircraft interiors,  the tools we buy and the utensils found in the kitchens. *So why not in model railroad design?*
- We can borrow on portions of industry’s research in order to create layouts that will be more ergonomically efficient for ourselves as we build and maintain them, and for our friends and guests who operate them.
- The Payoff: As an ageing group, we’ll feel less stress while working on the layout and be able to operate for longer periods of time.

## The Layout with Ideal Ergonomics 

- Will be at the perfect height for everyone.
- Will be deep enough for dramatic scenery.
- Will be shallow enough to be easily maintained.
- Will be high enough off the floor to permit a comfortable vertical workspace underneath.

## Taking it from the Top... as well as the front, sides and bottom

- We’ll examine layout design from multiple axes:
- X  - Permissible Lateral Space (under the layout)
- Y  - Permissible Depth
- Z1  - Permissible Overall Height
- Z2  - Permissible Vertical Clearance
- We’ll also see whether the materials used to build layouts might drive some ergonomic advantages.

## Ergonomic AxisObjectives

## Permissible Lateral Space: X Axis (the easy stuff) 

- Objective: To have access below the layout be as unencumbered as possible
- Cut off risers that drop below the designed low points in the bench work.
- Install soft cushioning materials on hazardous corners.
- Eliminate vertical support legs in favor of cantilevered bench work that employs angular support members.
- Route wiring to eliminate sags and loops that catch on tools and fingers while working under the layout.
- Install permanent work lighting and convenience outlets.
- Eliminate all ‘permanent’ clutter.

## Permissible Depth: Y Axis 

- Objective: All workers and operators will be able to reach to the furthest depth point with the least amount of effort.
*Depth, as measured horizontally from the plane of the fascia to the physical feature on the layout surface most distant from the fascia*

## Permissible Overall Height:  Z1  Axis

- Objective: The height and proximity to layout features will be in comfortable reach for most everyone who works on or operates the layout.
*Height, as measured vertically from the standing surface in the operating aisle to the railhead.*

## Permissible Vertical Clearance: Z2  Axis

- Objective: The under-layout clearance will permit a comfortable environment for most everyone who needs to work there.
*Clearance,  as measured vertically between the floor directly under the layout and the typical lowest point under the bench work.*

## Ergonomic Layout Design By the Numbers

## Starting Assumptions

- We’re dealing with adults of average mobility, who have limb and trunk lengths that are consistent with their particular height.
- The average total thickness of the bench work, roadbed and track is ~6” or less. Exceptions are noted for instances of extreme layout topography such as ravines and canyons where the bench work can drop well below track level.
- Builders and operators will be working in close proximity to, but not leaning over the fascia.
- There will be minimum obstructions under the layout.

## Sizing Them Up

| Height | Eye Level | Arm Length | Sitting Height |
| --- | --- | --- | --- |
| 5'  0' | 56 to 57" | 23" | 28" |
| 5'  2" | 58 to 59" | 24" | 29" |
| 5'  4" | 60 to 61" | 25" | 30" |
| 5'  6" | 63 to 64" | 26" | 31" |
| 5'  8" | 64 to 65" | 27" | 32" |
| 5' 10" | 66 to 67" | 29" | 34" |
| 6'  0" | 68 to 69" | 30" | 35" |
| 6'  2" | 70 to 71" | 31" | 37" |
| 6'  4" | 72 to 73" | 32" | 39" |

## Y Axis

- Permissible Depth

## Layout Depth Chart

| Height | 

Arm | Realistic Reach (from fascia plane) | Max. Depth |
| --- | --- | --- | --- |
| 5'  0' | 23" | 19" | 17" |
| 5'  2" | 24" | 20" | 18" |
| 5'  4" | 25" | 21" | 19" |
| 5'  6" | 26" | 22" | 20" |
| 5'  8" | 27" | 23" | 21" |
| 5' 10" | 29" | 25" | 23" |
| 6'  0" | 30" | 26" | 24" |
| 6'  2" | 31" | 27" | 25" |
| 6'  4" | 32" | 28" | 26" |
|  |  | All of the above assumes a proportional railhead height |  |

## Z1 Axis

- Permissible Overall Height

## Using An Eye Level Calculation to Determine Railhead Height

- The eye level calculation will help to determine layout height
- The calculation is easy but should be made with each of the people who will be regular operators.

## Optimum Layout Height Derived from an Eye Level Calculation

- Measured with the individual standing 12” from a vertical surface, such as a wall.
- Have them tilt their head down to a comfortable angle and look at an imaginary spot on the surface.
- Measure the distance from the floor to that spot. Mark it with a piece of tape.
- Repeat the measurement with the person standing at 18” and 24” from the wall.
- Average the heights of the three spots
- The resulting number will be the ideal layout height for that individual.
*Note:     The most comfortable height is going to be between 60 and 65% of the      **	**person’s actual height. A variable in this test between two people of **	**the same height can occur if one is wearing bifocals and one is not.*

## Railhead Height Chart

|  |  |  |
| --- | --- | --- |
|  |  |  |
|  |  |  |
|  |  |  |
|  |  |  |
|  |  |  |
|  |  |  |
|  |  |  |
|  |  |  |

| Eye Level  | Operator Ht. | Railhead Height |
| --- | --- | --- |
| 4’9” | (5’0”)  | 38-39" |
| 4’11”  | (5’2”)  | 39-40" |
| 5’1” | (5’4”)  | 40-41" |
| 5’3” | (5’6”)  | 41-42" |
| 5’5” | (5’8”)  | 42-43" |
|  5’7”  | (5’10”)  | 44-45" |
| 5’9”  | (6’0”)  | 45-46" |
| 5’11”  |                     (6’2”) | 46-47" |

## Z2 Axis

- Permissible Vertical Clearance

## Z2: The Under-Layout Vertical Space

- 	Whenever possible, try to aim for the most vertical space you can achieve under the layout. Make your calculations for someone who is in a relaxed sitting position on a 12” high chair, with legs outstretched. Give the person at least 4” vertical clearance from the top of their head to the average low point on the bench work. The following chart will help.

## Z2 Clearance Chart

**	****Height****	****Seated Ht.**
- 5'  0'		28"
- 5'  2"		29"
- 5'  4"		30"
- 5'  6"		31"
- 5'  8"		32"
- 5' 10"		34"
- 6'  0"		35"
- 6'  2"		37"
- 6'  4"		39"

- Add 16” to the seated height...
- 12” high seating surface
- 4” clearance to underside of layout

## So What Has BeenLearned?

## There’s a Vertical Conundrum

- The ideal under-layout vertical clearance will always be a number greater than the optimum layout height for that person’s height.
- The answer to ‘Which is more important, my railhead height or my under-layout clearance’ will subjective. Except...
*	**a. You can elevate the aisles with raised walkways, while keeping the space under the bench work at grade level.*
*	**b) You can reduce the overall thickness of the bench work and scenery to gain precious Z**2.*

## Conclusions

- The vertical conundrum suggests that single level mushroom layouts are probably the most ergonomic and offer other advantages such as improved square footage utilization and elimination of stacked operating areas.
- Single level layouts with raised walkways would seem to be the next most ergonomic.

## Engineered Materials

## Engineered Materials

- Engineered materials make it possible to have layouts that can be...
- much lighter in weight
- potentially thinner in overall thickness
- less expensive to build
- needing less physical support
- potentially ergonomically friendly

## Engineered Materials

- High Performance Bench Work & Supports
- 1/8” Plywood, fabricated into engineered shapes
- High performance adhesives.
- High strength joints that are stronger than the parent materials.
- Lends itself to either foam insulation board or cardboard web scenery
- Cantilever bench work by using thin-section fabricated wall brackets.
- _Industrial Correlation_:
- a) Commercial and residential construction use of glue-laminated beams
*b) Commercial  aircraft industry relies upon adhesives to build the skins of*
*    **today’s aircraft. *

## Concluding Thoughts

- Not an expert, just thinking in common sense terms.
- Existing Layouts: Contemplate what you can do to improve access for work,  maintenance and operations.
- New Layouts: Consider ergonomics and materials as you design and build.

## Thanks For Listening

- For an electronic copy of this material, send your email request to:
- l_dahlstedt@earthlink.net