Ramps as part of the set design

[IJWesley]

Hi

 

The director/designer of the show I am working on (in Sydney) would like a ramp on the stage for artistic effect. I'd like some advice on the maximum gradient that would be prudent.

 

The ramp top will be 2400mm in length and only used for actors to walk up/down and to stand on. As far as I can ascertain, it will not be used for wheeling anything up or down.

 

A search of the forum would suggest that if this were a building access ramp, a gradient of about 1:12 would be appropriate, givinn a drop of about 200mm and a slope of 5 degrees. However, the director would like a drop of 500mm (ie about 1:5, angle of 12 degrees).

 

In my view, this is far too steep for safety, but I'd appreciate comments, and pointers to any other information that is available on the www.

 

Ian

[paulears]

I've lit a couple of shows with odd set with ramps and other strange shapes - One ramp was difficult to go up and down - the compromise was simply bolt on batten ebery foot or so - this worked perfectly well.

[Piers Shepperd]

Hi Ian,

 

This comes down to your risk assessment!

I did a ramp recently which was very steep at 36deg. You couldn't walk down it easily but take a look;

36 Degree Ramp

However we certainly wouldn't let any cast to walk down it as part of the show.

 

Refer to architecture as a starter e.g. look in your library for 'Neufert Architects’ Data' - This gives us a guide;

Wheel chair ramps 6%

Ramps with non-slip surface 6-10%

Steep ramps 10-24%

 

As another guide there are too main kinds of scaffold type staging in use.

Kwikform (ESS & others) - Bay size 2400mm - vertical height of 495.5mm

Layher (Stageco & others - Bay size 2072mm - vertical height of 500mm

 

1) This means your proposal of a drop of 500mm over 2400mm is considered a 'steep' ramp but not extraordinary in the events world.

2) This means you can safely proceed to doing your Risk Assessment (based on a mock up maybe);

Looking at the following things;

a) Risk of wheeled objects being used on the ramp

b) Action being asked to take place on the ramp e.g. are people running, walking etc and what that might mean in the event of a fall

c) Risk of slipping. Can this be mitigated by using a non-slip surface? Will there be any rain or water?

d) Surrounding environment - if people slip and fall what will they hit? and can you make that safer?

e) Do you need a kick rail?

f) Do you need a handrail?

g) Will there only be actors / crew potentially on this ramp? (i.e. no public)

h) Anything else - you are responsible for this not me!

 

3) This should give you a feel for the topic, which you must then feed back and discuss with your team.

 

I don't know what your position / role is within the production, but as ever you must be 'compentant' to complete the above - don't guess at it!

 

Cheers,

 

Piers

[DavidLee]

... the director would like a drop of 500mm (ie about 1:5, angle of 12 degrees). In my view, this is far too steep for safety...

We have innumerable roads steeper than 1:5 and I've never seen pedestrians banned on safety grounds!

 

Just looked back over my stage plans and we have an 8ft ramp used to access a 2ft stage from the auditorium floor - that's 1:4 or 14 degrees. Actors have never had any problems using it. However it does have a ridged rubber non-slip surface.

 

David

[IJWesley]

Many thanks for the info.

 

Just a bit of background - the show is an amateur production being performed in a church hall environment using the existing stage. The ramps in question will run parallel to the front of the stage, rather like a ramped stage extension 1200mm deep (see picture).

 

My involvement is to provide assistance and guidance where necessary and appropriate as I have been involved with the group for many years and have produced/designed/directed many shows in the venue. Basically, I know what we have got and what is possible on the budget.

 

My day job (what I get paid for) is a scientist, where one of my responsibilities is safety officer for the company - hence my nervousness about the safety issues. This particular problem is not somethig that occurs in my sphere of experience on a daily basis (nasty chemicals are a breeze though!)

 

My main concern is that the actors will be asked to do something more energetic than simply walking up or down the ramps.

[Piers Shepperd]

Two things I'd add or suggest to the team;

 

1) to add a flat 1200mm x 1200mm flat deck offstage L+R at the same height as the existing main stage, before you go down the ramp. This just reduces the risk of tripping as people move on and off the main stage.

2) add a 50mm x 50mm very low wooden batten to act as a guider kick-rail on the downstage edge of the ramp. this doesn't actually give you anything meaningful, but will give people something they'll feel with their feet if they come too close to the edge.

 

Cheers,

 

Piers

[tom w]

I would tend to agree with Piers. Our (layher based) modular production ramps are 500m lift over a 2072 bay. Giving slightly better than 1:4. This is fine for short runs and perfectly safe to walk up and down. If you are to do without a handrail, I would definately ensure a grip surface is added!

For longer runs the gradient needs to be less, or have a flat bay every few bays.

For Accessible Viewing Platforms you need 1:8 for assisted access or 1:12 for self access. There was some talk of 1:20 for building regs, which generally filter to the event industry over time. How your average AVP would look with a 20m long ramp for 1m height is another story.

Regards,

Tom

[Ike]

My main concern is that the actors will be asked to do something more energetic than simply walking up or down the ramps.

In the industry performers do things that would be classed as dangerous in real life (e.g. a dance routine near an open pit) with the understanding that they are a repeated, rehearsed, controlled activity for which they have received sufficient training and gained sufficient experience, i.e. they are competent.

Start with walk-throughs in good light and slowly speed it up, asses the performers continuously and stop them if you feel its unsafe, make sure they are happy to stop if they feel unsafe, watch them closely through technical rehearsals and make sure they are happy. Treat it as a stunt and I can't see there being any problems.