Operators of heavy earth-moving equipment must be well trained and must know the hazards associated with heavy equipment operations. Observe these common precautions:

Driving and Operating

Before starting any equipment, be certain that it has been inspected and serviced according to the regular schedule.
Before hooking up equipment, make sure any attachments are lowered, the shift lever is in neutral, and the brakes are set.
Make sure everyone is clear before moving or backing up.
Never leave a machine on an incline with the engine running. Vibration may put the machine into motion.
Never allow people to ride on the equipment.
When operating equipment on an active road, display flashing lights and a slow vehicle triangle.
Never coast down a hill.
When working near trees, watch for dead branches (“widow-makers”) above the equipment.
Use great care when working near the edges of cuts or fills.
Most mobile equipment is required to be ROPS equipped. Be sure equipment is properly equipped.

Maintenance and Repair

Shut off engines during refueling.
Shut off equipment before making repairs.
When equipment is under repair, place a sign “Under Repair” in the seat, remove the start key, or lock out the controls.

Parking and Security

Always lower attachments and set the parking brake before dismounting the equipment.
Always set the brake, lower the equipment, and place the shift lever in neutral at the end of each work shift.

Secure the equipment when finished for the day. Make sure it is clear of traffic. If it is not clear, mark it with glares or red lights. Lock it up.

Buying a Dozer or Earth Moving Equipment

Anytime most of us envision a work site where there is the potential for demolition or earth work, the first piece of equipment which will come to mind is a bull dozer. Dozers can range in weight from 100,000 pounds (50 tons) to 160,000 lbs or 80 tons. Dozers are in the heavy equipment category and essential in open pit mining. Dozers or mobile equipment usually are fitted with a heavy blade which is attached to the front of the equipment.

Types of dozer blades can vary depending on the project scope or work which is to be performed. The common types of blades which are used on a bulldozer include:

1. Universal blade- a universal blade is a curved shape blade which is required to move or push bulky materials.

2. Straight blade- a straight blade is generally used for fine grading.

3. Combination blade- as the name suggest, this blade is a combination of a straight blade and a universal blade and which manages a dual purpose of fine grading and carrying bulky materials forward.

Dozers have come a long way since their inception in the 1920's and are even used in the military where they tow tanks, prepare roads and displace burnt equipment from rough terrain areas.

They are usually equipped with steel tracks which enable them to work on muddy or rough terrains. These tracks offer stability or traction on sandy or muddy terrain.

Bulldozers can be equipped with a rear attachment. The most common attachment is a called ripper shank or tooth which helps loosen densely-compacted soils. A large bulldozer usually has only one shank on the ripper, and a small bulldozer generally has multiple shanks. The shank is considered a wear part or ground engaging part which is replaceable as and when required.

GPS in the Earthmoving Industry

GPS Technology was officially introduced as a guidance system for earthmoving machines in the late 1990s. Since this time, many manufacturers of earthmoving equipment now offer GPS and other guidance systems as a factory option. Many companies exist that also sell GPS guidance systems for the earthmoving industry as a retrofit option.

GPS when applied in the earthmoving industry can be a viable asset to contractors and increase the overall efficiency of the job. These systems allow the equipment operator to use GPS position data to make decisions based on actual grade and design features. Some heavy equipment guidance systems can even operate the machine's implements automatically from a set design that was created for the particular jobsite. GPS guidance systems can have tolerances as small as two to three centimeters making them extremely accurate compared to relying on the operator's skill level. Since the machine's GPS system has the ability to know when it's off the design grade, this can reduce surveying and material costs required for a specific job.

GPS Applications

The key to successfully using GPS in the earthmoving industry is having an accurate site design. The site design, typically created by an engineering firm, can be imported from the original design file into the machine's GPS display. Most GPS guidance systems also have the ability to allow the operator to define a specific grade elevation or grade angle without a specific design. The following describes common machine applications that utilize GPS guidance systems.

Track-Type Tractors

TTT are an extremely popular machine platform for GPS guidance systems specifically in the smaller sized models that are used for fine grading. One example of GPS being used on a TTT would be on a road project.

Motorgraders

Motorgraders are another popular machine platform since they also perform fine grading activities that can benefit from the GPS accuracy.

Hydraulic Excavators

Hydraulic excavators are just beginning to be integrated using GPS technology and are typically indicate only. Excavators use GPS technology in conjunction with angle sensors integrated in the machine's boom, stick, and bucket. This allows the operator to see how deep they are digging by comparing the actual bucket location to the site design on the GPS display.

Scrapers

Scrapers use GPS technology and are typically indicate only. The GPS antenna is typically mounted on the bowl of the scraper and allows the operator to compare the depth of the cut versus the site plan. This takes a lot of the ambiguity out of moving large amounts of material.

Compactors

GPS technology is applied in both trash compactors and soil compactors. Typical systems record where the compactor has been in order to create a map of the area's compaction. Usually the display has various colors that indicate that the machine has compacted the area.

GPS Limitations

GPS is extremely versatile in the earthmoving industry but it does have its limitations. GPS satellite signals can only be received in a non obstructed view of the sky with the exception of clouds. If a contractor wanted to perform grade work in preparation for a concrete floor within a building for example, the roof would block the view to the GPS satellites preventing the system from working. Working too close to a structure can also obstruct the machine's view of the sky creating dead zones. GPS satellite coverage can also be weaker during certain parts of the day lowering the amount of satellites the machine's system can use. This all depends on the geographical location and time of day.