Seal Appeal: Dock Seals' Saving Graces

A modern loading dock may be extremely efficient in many ways. Capable cargo handling depends on a number of factors but two specific features stand out over the rest. Moreover, they interrelate.

The two allied notions of getting the trucks to the goods and getting the goods to the trucks sound simple. They are simple enough but in relating with one another, they have a downside. Placing the truck to be loaded close to the dock that will load it is an obvious requirement. Having an aperture that allows the goods to be taken on or off the truck is equally obvious; the resulting disadvantage isn't necessarily so apparent. Simply, where goods can go, so can wind, rain, sleet and snow, which is why a means of protecting the goods concerned, as well as the personnel handling them, is needed.

There are two devices for keeping the elements at bay, while also keeping the expensively-heated interior of the loading dock at a comfortable working temperature. Dock shelters and dock seals both offer weather protection and the maintaining of loading dock temperature; here, we'll look at the latter.

To work effectively, dock seals must meet a number of needs. To work effectively over time, they must meet further needs. The good news is that, as they are made to a proven design and constructed using modern materials, good quality dock seals will do what their name implies over a lengthy service life.

So, what must dock seals be capable of doing? As the compressible medium that temporarily makes the loading dock and a truck into a single unit, they have to be able to…

• Accept the compression load imposed as the truck is reversed against them.
• Spread this compression load evenly over their mounting surface.
• Maintain a heat-retaining, weather-resistant seal between the truck and loading dock.
• Resume their original profile quickly when the truck is driven away.

Modern dock seals fulfill these demands without demur, by courtesy of the experience that goes into making them and through the materials used in their manufacture. They have an energy-absorbing core that transmits the load the truck puts on them evenly around the aperture they're protecting. Their external skin is resistant to chafing, proof against damage by heat and penetration, and is capable of re-forming quickly even in low temperatures.

What happens if the truck is pressing too hard against the dock seal? In a word, nothing, because over compression cannot happen. Generally, the maximum allowable compression (i.e. the minimum permitted thickness of the dock seal) is in the order of 150 millimetres. A buffer stop is incorporated into the installation and this allows the truck being unloaded to compress the dock seal so far and no further.

This is all well and good but for two parameters relating specifically to trucks. In an ideal world, trucks' tails are vertical and a dock seal with a square section profile will work perfectly. The world, however, isn't always ideal and some trucks don't have a vertical tail. This is solved by the availability of dock seals with an angular section profile. Similarly, vehicle heights vary; to cater for this, dock seals can have adjustable head pad units – problem solved.

As will now be clear, dock seals provide a workable, efficient solution to keeping goods clean and dry, and the loading dock warm, in all conditions. Choose a high quality, well designed, durable dock seal installation and efficiency will be enhanced.

Chase Equipment are a leading international supplier of dock seals. See our website at Chase Equipment for more information.

Hot Topic: Identifying Dock Seal Fire Risks

Ten years ago, loading dock seal fires in the USA suddenly became big news. The number of fires reported peaked suddenly in 1999, to the bafflement of those concerned. Even the firefighters were mystified until investigations revealed the cause. As a consequence, something could be done about the problem.

As we probably all believe, loading dock seals are just there. They keep goods dry, keep the heat in the buildings they serve and, given regular safety inspections, aren't likely to be too much trouble. So why did they start going up in flames in considerable numbers? The answer's simple – when you know it. It turns out that Federal Motor Vehicle Safety Standards were to blame. They required vehicles of a given size to have three rear identification lamps and two rear clearance lamps near the upper edge of their trailer. Drivers were loading or unloading with these lights on. The fitting of bigger alternators to the vehicles, to run an on-board TV, a VCR, a microwave oven, a satellite dish and/or GPS was making matters worse by over-driving the lights, making them prone to overheating. In any event, it was discovered that in as little as 20 minutes, a temperature high enough to cause foam-filled loading dock seal pads to ignite could be reached.

This begs a question: what has this to do with loading dock seals in the UK? Well, in the USA, it's estimated that there are over 100,000 loading docks with compression-style
foam dock seals with unprotected head pads. So what? Any loading dock seal material may be fire-retardant but it has a service life and its fire-retarding abilities can degrade with time. Moreover, the material isn't necessarily fire-resistant and in the UK, lorries have lights. The bottom line is that if you see scorch marks, let alone holes burnt into the material, a danger exists. Such marks suggest hidden damage that must be addressed.

Does this cautionary tale say it all for the fire risks associated with loading dock seals? In a word, no. Like any safety issue, fire safety needs attention. Unlike some safety issues, it isn't something that can be – let's say, put on the back burner...pun intended.

While many of the safety aspects of fire risks in relation to loading dock seals involve commonsense, there are elements that demand special caution. You may be proud of your company's fire safety arrangements, citing installations including smoke and fire detection alarms and an automatic sprinkler system. These are all well and good but their effectiveness – and therefore their value – is very much dependent on what materials you handle.

In 2006, a lorry load of cream cheese caught fire, closing the eastbound carriageway of the A55 at Colwyn Bay. This was down to a burst tyre causing a lorry fire but bring it closer to home and it's no fun. Should you be handling flammable materials, you need to safeguard against their ignition. How? There are cargo-handling techniques, such as limiting the amount of inflammable material held at any one spot at a given time. There are gas detectors, should you be handling this material. There is also a very important rule concerning the point where a loading dock seal will be fitted. This is quite simple: never consider a loading dock as an emergency fire exit. On more than one occasion, personnel have attempted to escape., become wedged between the dock and a lorry – and died.

It's a sobering but unarguable fact that commonsense isn't always enough...and there's no shame in seeking help. From whom? The fire brigade. A Fire Safety Officer will hold the rank of Watch Commander and may rank higher still. Above all, he or she will be trained to spot the risks for you. 'Better safe than sorry' is an old adage but it applies as much as it ever did. Should you be in any doubt, think about this. Suppose there was a fire in your loading dock? Enough said.

Chase Equipment are a leading international supplier of loading bay equipment. See our website at Chase Equipment for more information.