Most garages and filling stations now offer a jet wash in addition to the standard automatic car wash. Jet washes score over automated car wash facilities in these key areas:

• Rather than washing the whole car to a uniform standard, they allow the operator to concentrate on where cleaning is really needed, like areas of ingrained dirt.

• They are far less likely to snap off aerials, uproot wiper blades and tear off pieces of trim.

• They are generally cheaper.

• They can be fun to use.

• They may be used on a wide variety of shapes, sizes and types of vehicle, as well as for cleaning other suitable items.

A few words of warning: You would be ill advised to use a jet wash on an open-topped car unless the optional roof is attached and securely shut.

Guidelines on the Use of a Jet Wash

Before leaving home, take a moment to consider your clothing. Much of your body will be subjected to at least a little spray as you use the wash, and your feet will become particularly wet from both falling water droplets and from any puddles accumulated on the ground. If it is a hot day you may not mind this, otherwise you should wear clothing appropriate for light drizzle and remove your watch, mobile phone and other non-waterproof items if necessary. It is a good idea to have a tissue in your pocket, as will become apparent later.

Prior to using the jet wash, the usual procedure is to park your car out of the way somewhere while you go inside the forecourt kiosk. You should lock the car while you do this. At the kiosk you can give the cashier some money in exchange for a token, which you'll need to operate the wash. You are usually presented with a choice of different types of wash against a list of prices on an escalating scale. The type you choose will depend on how necessary you feel it is to have as clean a vehicle as possible, and... available finance.

On this last point, it is not considered appropriate etiquette to pay for a jet wash with a credit card or cheque unless combining this cost with some other, proportionally larger purchase, such as petrol.

The final choice is a personal one, however this Researcher recommends selecting the most expensive wash which excludes the waxing option. This will give you a good compromise between effectiveness and cost. Wax can give a gleaming finish, but paying more for a waxing cycle has mixed advantages as the wax can adhere to the car's windscreen and impede vision in the rain and at night.

Some machines are coin operated, in which case the above choices need to be made at a later stage, when parked directly in front of the jet wash.

Having obtained a token, or ascertained that you have a good mix of local currency coinage as appropriate, you should drive your car to the jet wash facility. It is possible that other users, who have either started their journey earlier, had a shorter distance to travel and/or made their way to the jet wash at a higher velocity, will have arrived before you. It is customary to adopt a queuing system on the basis of first come, first served. If you do not conform to this protocol you are likely to be verbally challenged by the other users.

Once it is your turn to proceed to the jet wash area, you should note that positioning is of some importance. Examine the point from which the hose or hoses extend. Using your knowledge of geometry and taking into account both the length and elasticity of the hoses, and the action of gravity thereon, you should aim to park the car where it will be accessible from all angles, yet least likely to snag the hose as you traverse your way around. Should a hose happen to be draped across the area, do not park with any of the car's wheels on top of it. This would render the jet wash extremely difficult to use. It may be necessary to make a temporary stop just short of the wash area to jump briefly out of the car and manually throw coils of hosing to one side. There will often be a drainage hole in the ground for channelling away waste water, so an additional challenge is to park in such a way that the drain is not obstructed by the wheels of the car.

It is vital to ensure that all windows, doors and the sunroof are securely closed to avoid ingress¹ of water during the washing process -jet washes are intended exclusively for cleaning the outside of the vehicle. If you wear glasses, but are comfortable without them, you may choose to remove these as they can cover with spray and become a hindrance. Make sure that the token or money required is on your person and not left in the car. The last door to be checked is always the driver's, as this is closed from the outside after having stepped through it.

Most jet washes have two hoses, one terminating in the jet device from which the machine derives its name, and the other in a brush. It is a good idea to untangle the hoses at this stage, for as soon as the machine is started it will operate for a strictly controlled period of time and you will need to focus quickly on the job in hand. Satisfy yourself that the hoses are tangle and kink free and select the one with the jet. Familiarise yourself with the feel and action of the jet mechanism. The device is designed to be held with the nozzle facing away from your body in the manner of a machine-gun, with the handle tucked into the chest. You will be working at close range, so there is no need to hold the device to your eye like a rifle. The trigger is designed to be squeezed comfortably by one hand while the other hand is placed further up the barrel for steadiness. There is usually a rubber grip with which to hold the barrel, this being necessary because the metal parts become hot during operation.

At this point you should insert the token or money according to any instructions printed on the front of the machine. The jet wash machine should start to create a noise level of around 60dB accompanied by a noticeable vibration caused by the internal workings. The jet is then ready for use and will commence spraying cleaning fluid on squeezing the trigger.

You should be warned that the fluid is under extreme pressure and, unless you are trained in handling a firearm, you may not be prepared for the power of recoil when the trigger is pulled. In the author's experience, the basic body reaction to being thrown backwards is to thrust forwards clumsily in over-compensation. If the jet is being held close to the car when this happens, there is a very real danger of the nozzle hitting and scratching the paintwork. It is thus better to operate the trigger while standing a safe distance from the car, at least until you have established a feel for the forces involved.

Begin spraying the car freely. You can concentrate on areas of dirt such as mud or bird droppings, spray under wheel arches or just make swirly patterns with the foam. Make a mental note of any areas where the dirt is so ingrained that the spray alone cannot shift it - you can come back to these later with the brush.

After a period of time preset by the manufacturers of the machine, the jet wash will emit a new noise, this time of a much higher frequency. This is an alarm to warn you that the next phase of the wash cycle is about to commence. Should you want a last attempt to blast foam at a particularly resilient stain, this would be a good time. If you have opted for one of the cheaper cycles which excludes a brush wash, please skip the next paragraph.

Replace the jet in an available holster and pick up the hose with the brush attachment. At commencement of the brush wash cycle, yet more of the aforementioned white foam will begin dribbling from the end of the brush. Use the brush on any remaining mud and dirt patches. The brush is particularly well suited to cleaning parts with contoured shapes and deep recesses such as wheel hubs. It is important to note that most users will utilise the brush for their own respective wheel hubs in exactly the same way, especially if they should happen to have read this entry. Thus, unless you can ascertain that the machine or the brush are brand new, you may expect the brush bristles to contain all manner of contaminants gleaned from other people's car wheels, including road gravel. Caution is required in order to avoid these causing damage to paintwork. It is for this reason that the brush is usually used for wheels, bumper and light clusters alone, where scratches are commonplace anyway and are unlikely to effect the overall look and perceived value of the car. At the end of the brush cycle the warning alarm will again sound. Replace the brush in its holster and pick up the jet hose once more.

The next cycle is the final rinse. The jet is held and used in exactly the same manner as before, only water is ejected instead of foam. Use the water jet to rinse off all visible traces of the foam previously applied. It is normal to rinse the vehicle in a top-downwards fashion to avoid foam migrating onto areas already rinsed, under the influence of gravity. Don't forget to rinse out the wheel arches and any other hidden areas where cleaning foam may lurk. Operate fairly quickly lest the rinse cycle end before you have removed all the foam. 'Chase' any clods of mud away down the drain with the jet, otherwise you may drive through these when you leave and muddy the car again.

The rinse cycle employs cold water for the task and, if the ambient air temperature is uncomfortably warm, you may wish to take advantage of the cooling properties of the water by allowing spray to accumulate on your clothing and body. Firing the jet vertically into the air above and letting the spray fall on your head can be a rewarding and tactile experience, though asking a partner or a bystander to fire the jet directly at you would be considered too extreme by most.

A final alarm signal from the machine will warn you that the end of the rinse cycle is near. Hang the jet device in its holster and push any drooping coils of hose to one side as this will be helpful to the next user. Walk around the car to check for any damage. Most garage forecourts display a disclaimer notice stating that customers use the facilities at their own risk, but this is not strictly true from a legal standpoint. Sure enough, if you cause damage to your car through misuse of the jet wash then you cannot expect compensation but if, for example, a piece of the machinery or roofing falls onto you or the car then you still have full legal rights despite any disclaimer.

Paradoxically for a cleaning device, some parts of the jet wash may be fairly dirty and you may find that your hands are less than clean by this point. Your tissue will come in handy here should you wish to avoid spreading any dirty fingermarks on the newly-cleaned paintwork or on the steering wheel of your car.

Having inspected the car, climb back in and drive forward carefully onto the main forecourt area. You should test the brakes before moving onto the open road as brake pads and discs will have become wet. This completes the jet wash procedure.

Other Uses

One of the advantages of a jet wash is that it may be used to clean items other than cars, though there are limitations. Electrical goods, upholstery and devices with delicate or intricate moving parts would be unwise choices. Most vehicles including cars, vans, caravans and bicycles may be washed by this method to good effect. Never use a jet wash to clean pets or livestock.