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Dragons Teeth FAQs
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Q. How do Dragons teeth actually work?
Q. Will they make all the traffic go one way?
Q. We charge money for parking can we stop people leaving without paying?
Q. We have a lot of trucks on our site will they break them?
Q. Can I lock them down; sometimes we want to go both ways?
Q. Do they slow the traffic down?
Q. Are they noisy?
Q. . Will they puncture the tyres?
Q. Will they damage vehicles going the wrong way?
Q. Will they bolt down on my road?
Q. What about cyclists and pedestrians?
Q. What happens if one of the spring's breaks and it get stuck down?
Q. Can we install them and how long does it take?
Q. Do we need to have signs?
Q. Am I responsible for any damage caused to a vehicle that drives over the wrong way?
Q. What maintenance do they require?

Q. How do Dragons teeth actually work?

a. It is mainly a visual thing. Dragon’s teeth are not going to burst the tyres of offending drivers. When you see these teeth in front you it is clear that the “spikes” go down when you drive in the right direction. People feel confident that they are allowed to drive over and they will be safe. However, if you are attempting to drive in the wrong direction the bright yellow steel teeth generally give drivers a much clearer message i.e. to back up and go another way. Drivers take the common sense approach not to drive over to avoid the risk of any damage.
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Q. Will they make all the traffic go one way?

a. A qualified yes. A HGV’s wheels are much larger than Smart cars so on some level the deterrent is less but clearly the potential for damage if you drive the wrong way is still there. Installing Dragons teeth makes a statement, we are serious about traffic control and the vast majority of drivers will respect that.
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Q. We charge money for parking can we stop people leaving without paying?

a. No. The determination of drivers to avoid payment is legendary. Our product is designed to enforce your traffic control and make your car park or site roads safer not more secure.
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Q. We have a lot of trucks on our site will they break them?

a. Heavy trucks have more axles and wheels to distribute the load. Driving in a straight line over the product is within the working limits. When designing the layout avoid allowing vehicles to turn or drive over the teeth at an angle. Back to top

Q. Can I lock them down; sometimes we want to go both ways?

a. Yes in a fashion. We do not lock the teeth down; the conditions down at ground level are so harsh mechanical locks would fail over time. There is a simple steel cover plate, 500mm long section yellow and black. When the steel checker plate covers are in place the teeth are transformed into a metal speed ramp, allowing traffic to drive in both directions.
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Q. Do they slow the traffic down?

a. Definitely. As vehicles drive over the teeth go down from a 100mm high to 50mm high. The profile of the product (with teeth down) is of a 5 to 10mph metal speed ramp, very effective. Back to top

Q. Are they noisy?

a. No, unlike the counterbalanced foundation versions that made a clatter as vehicles drove over the spring operation these teeth are virtually silent.
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Q. Will they puncture the tyres?

a. No. We are a safety company. That said we have supplied a tyre-bursting version for the military for very restricted use at security and manned control points. Back to top

Q. Will they damage vehicles going the wrong way?

a. Possibly. Going in the wrong direction, against the flow, can cause damage to any low-slung part of a vehicle. The teeth will be against their backstop and will effectively pull down something like a badly fitted exhaust system. Back to top

Q. Will they bolt down on my road?

a. We use the very proven fixing system developed for installing speed ramps. Tarmac, asphalt, concrete and block surfaces are ideal. Watch out for any pronounced camber in the centre of the road our steel teeth units are one metre long sections and not flexible. Back to top

Q. What about cyclists and pedestrians?

a. Neither want to pass over Dragons teeth so we supply splayed end shoulders (200mm wide) so that type of traffic can pass safely at the gaps left at each end of the installation. Back to top

Q. What happens if one of the spring’s breaks and it get stuck down?

a. We tested it 3 million times but things do break. Each tooth is in a cassette that can be easily removed and either re-sited or replaced. On a typical installation only 50% of the teeth ever come in contact with a vehicles wheels. Back to top

Q. Can we install them and how long does it take?

a. We do carry out install but everyone seems to be able to fit them their selves. You need to drill six 14mm x 100mm deep holes per metre section and we supply the anchor bolts. A typical 3-metre section takes a couple of hours to fit. For H&S it is recommended that you divert the traffic using chapter 8 approved safety equipment and the fitters wear high visibility waistcoats. Back to top

Q. Do we need to have signs?

a. Yes and we are not saying that because we sell them. Drivers need clear instructions using reflective MOT signage. The red and white No entry is the most important. Any driver with a driving licence knows what that sign means and should not be attempting to drive the wrong way! Back to top

Q. Am I responsible for any damage caused to a vehicle that drives over the wrong way?

a. To limit your liabilities use reflective MOT signage i.e. no entry a red circle with a white bar to stop any civil claim that driver was not informed correctly. It would be hard to explain to a judge that you held a UK approved drivers but you did not know what a no entry sign meant. Back to top

Q. What maintenance do they require?

a. Use Rocol instant grease in an aerosol form to lubricate the teeth every 6 months. Back to top