Trailers - Safety with a hitch

by Ray Hopkins, BAS, Project Coordinator, CSAO

 

Contractors frequently transport equipment and materials on trailers. Towing in construction typically employs either a pintle hook or, less frequently, a ball-and-tongue hitch. Both pose similar safety concerns. This article highlights general precautions for trailer safety on streets, roads, highways, and other public routes. For specific instructions, refer to the operating manuals for vehicle, trailer, and hitch. The Highway Traffic Act stipulates requirements for trailer towing. (This article doesn’t cover fifth-wheel towing.)

Inspection and Maintenance

Every employer should establish a system to periodically inspect, repair, and maintain vehicles and trailers. Such a system ensures that trailers are checked regularly and allows easy access to service records. Trailers are often used by different drivers and can be stored over a season. Drivers who don’t know a trailer’s maintenance history should check its condition and be satisfied that the equipment is fit and ready for service. A driver who thinks that a vehicle or trailer isn’t safe should advise management accordingly. Employers must not permit vehicles or trailers on public roads if there’s any reason to believe the equipment doesn’t meet safety standards.

The maintenance system should include checklists based on operating manuals and other manufacturer’s information. For most trailers, pre-trip inspection should cover

• maintenance records
• hitch
• pintle hook and draw bar (or ball-and-tongue)
• safety chains
• safety pins
• wiring
• lights
• tires and wheel nuts
• brakes
• flooring
• load
• tow vehicle.

Maintenance Record

The record indicates service history such as when bearings were last greased. Don’t overlook routine maintenance. Follow manufacturer’s instructions.

• Clean trailer and check for proper operation.
• Inspect for worn, cracked, or damaged parts, and replace as required. Don’t weld or modify manufactured components or strike parts with a hammer – a hammer blow can cause a hairline crack invisible to the eye.
• Apply lubricants as required.
• Check and grease wheel bearings when necessary.
• Check fasteners and re-torque if necessary.

Hitch

Verify that the rated capacity of the hitch on the vehicle is equal to or exceeds the gross trailer weight. Capacities are usually stamped on hitch accessories. If not stamped, look for capacity stickers. Worn or damaged stickers can be replaced by contacting suppliers.
The weight of the trailer plus its load determines the class of trailer hitch that must be used:

• Class I – up to 2,000 lb.
• Class II – up to 3,500 lb.
• Class III – up to 5,000 lb.
• Class IV – up to 10,000 lb.

Hitch classes are identified in CSA Standard D264-1796.

Pintle Hook and Draw Bar (or Ball-and-Tongue)

Combination Pintle Hook and Ball Hitch

Tow equipment and accessories must match. Ensure that pintle hook and draw bar (or ball-and-tongue) have adequate capacity for the trailer. The tongue must fit snug on the ball. A 2” tongue on a 1 7/8” ball will fit, but won’t be snug. Manufacturers usually stamp capacities on components. Check that moving parts function properly. Ensure that latches close fully. Insert latch pin after closing.

Safety Chains

A trailer requires two separate means of attachment to the vehicle (not applicable to fifth-wheel towing). A typical arrangement incorporates a pintle (or ball) hitch with two safety chains. Ensure that these are attached correctly and have adequate capacity. Each safety chain must have a capacity equal at least to the gross weight of the trailer.

Chains should cross under the tongue to connect to the hitch or tow vehicle using a closed link.Open clasps (or hooks with faulty or missing safety catches) are not permitted. The clasp must also have a capacity rating equal to the gross weight of the trailer.

Safety chains are crossed so the tongue will be cradled in the crossed chains instead of dragging on the ground if the tongue separates from the vehicle hitch. Adjust the chains to provide enough length to allow full articulation of the trailer, yet prevent the trailer coupler from striking the ground if uncoupling occurs.

Safety Pins

Safety (or locking) pins must be in place and in good condition. Replace weak or missing pins on hitch and trailer.

Wiring

Inspect wiring. Check for loose or frayed wiring, cracked insulation, or signs of corrosion. Clean and repair as required.

Lights

Connect and test for proper operation of all functions.

Tires and Wheel Nuts

Check tires for proper inflation, adequate tread, even wear, and overall condition. Ensure that wheel nuts are tight. Check condition of the spare if there is one.

Brakes

Some trailers have electronic brakes. The system includes wheel brakes that are activated in conjunction with the tow vehicle’s braking system. A brake controller is located in the tow vehicle. The driver sets the braking control to allow assisted braking while preventing lock-up.

Test and verify proper function of the trailer braking system in a safe location away from traffic. While moving slowly, manually operate the controller to apply the trailer’s brakes and verify their function. The trailer should slow down and stop the vehicle. After verifying proper function of the trailer brakes, apply the tow vehicle brakes while moving to ensure that the trailer brakes are not set too high – they should not lock up.

An emergency breakaway system incorporates a cable connecting the tow vehicle to a switch box on the trailer. In case of separation, the trailer’s brakes are automatically applied when the cable pulls the braking control switch apart. The switch should be tested occasionally for function (follow manufacturer’s instructions).

Flooring

Should be in good condition and able to support the load.

Load

• Don’t overload the trailer. Load weight must not exceed the trailer’s capacity rating. Overloading or poor load distribution can cause swaying during travel or damage to the trailer.
• Load the trailer to keep weight on the tongue. Generally tongue load should be 10% of gross trailer weight. Shifting loads can destabilize the trailer. For example, the load shifting to the back can lift the tongue off the ball.
• Avoid sudden stops and starts and quick turns. Otherwise high loads may tip over or the load may shift. When travelling on rough terrain or cornering, drive slow. When travelling on rough roads or terrain, reduce trailer weight by 25% for added safety and to prevent trailer damage.
• Secure or arrange loads so that no portion may become dislodged or fall off the trailer.
• Ensure that gates and latches on the trailer are functioning correctly and are secured before towing.
• Cover loose objects with a tarp.

Oversized loads require additional precautions because their height, width, or length (overhang) may pose hazards to the driver, other traffic, and property. Know the load restrictions for highway towing:

Width – not more than 2.6 metres.
If the load exceeds this limit, contact the local enforcement office of the Ministry of Transportation. A permit and extra lighting may be required for the vehicle or trailer.

Overhang – not more than 1.5 metres.
Loads extending more than 1.5 metres beyond the end of the trailer require a red flag or red marker big enough to indicate the load projection. A red light must be attached to the end of the load anytime between dusk and dawn from one half hour before sunset to one half hour after sunrise and whenever visibility is poor.

Height – not more than 4.15 metres.
High loads may contact overhead structures such as bridges, signboards, and powerlines. Before towing high loads, make sure you know the height of the load and of clearances along the route of travel. No vehicle, including the load, exceeding 4.15 metres is permitted on a public road. If the load exceeds this limit, contact the local enforcement office of the Ministry of Transportation. A permit may be required for the vehicle or trailer.

Inspect anchor points, ropes, chains, and slings used for tie-downs. Replace components that show signs of wear or damage. Rope defects include

• fibres burned or melted (other than on heat-sealed ends)
• diameter reduced by 20% or more
• repairs other than proper splices
• knots in the rope at other than fastening points.

Loading and Unloading

Under the Occupational Health and Safety Act, employers and supervisors have a general duty to take every reasonable precaution to protect workers. This includes advising workers of trailer dangers. Every load presents unique hazards. For example,

• a compressor, tar kettle, or welder may require workers to manoeuvre the trailer by hand
• a vehicle may have to be driven off a flatbed
• the load may require manually lifting and carrying materials to another location.

For more information on service vehicles, refer to Construction Safety magazine (Summer 2002 and Winter 2002/3).

For more information on the Highway Traffic Act, contact the local Ministry of Transportation Enforcement office or visit www.mto.gov.on.ca.

 

Tow Vehicle Manufacturer’s gross axle weight rating (GAWR) To comply with the Highway Traffic Act, the gross weight of a passenger or commercial vehicle (a van, for instance) and trailer must not exceed the manufacturer’s gross axle weight rating, which is usually found on a sticker placed on the driver’s door. Commercial vehicle When determining total weight, the trailer’s weight must be added to the weight of the vehicle. Add the highest weight of the vehicle to the highest of the trailer’s gross vehicle weight rating (if provided on trailer) or the actual weight, empty or loaded, to determine whether the combined weight exceeds 4,500 kilograms. Whenever the gross vehicle weight rating (GVWR), registered gross weight, or actual weight, loaded or empty, exceeds 4,500 kilograms, the vehicle and operator are subject to the regulations under the Highway Traffic Act that apply to commercial vehicles and commercial vehicle operators. Such operators must obtain a Commercial Vehicle Operators Registration (CVOR) as well as adhere to additional requirements such as annual inspections and carrying a pre-trip inspection report and logbook. A class A driver’s licence is required when the manufacturer’s gross vehicle weight rating of the trailer exceeds 4,600 kilograms. Commercial plates Commercial plates are required on any vehicle having a permanently attached truck or delivery body. The requirement for commercial plates on a van or pickup does not automatically classify it as a commercial vehicle. Commercial vehicle operator The Highway Traffic Act defines an operator as the “person responsible for the operation of a commercial motor vehicle including the conduct of the driver and the carriage of goods or passengers, if any, in the vehicle or combination of vehicles.” The operator does not necessarily have to be the vehicle owner. If the vehicles are leased or contracted, the operator must hold a valid CVOR certificate. Vehicle capability Ensure that your vehicle can tow the expected weight of the trailer. The manufacturer or dealer should be able to determine this. Aftermarket equipment, such as a transmission cooler, may be necessary to protect the vehicle from the added strain of towing. A good maintenance program should prevent vehicle breakdowns during travel. Consult the vehicle’s operating manual for specific towing instructions. Tow vehicles are subjected to heavy operating conditions. A poorly maintained vehicle is more likely to fail under the extra load of a trailer. Verify that the tow vehicle has been maintained in good working order before hooking up the trailer. Have your papers ready. Trailers being towed on a public road require both a permit and a number plate. The permit or a copy must be available for inspection. Use extra caution. Towing can make vehicles perform and respond differently. Drivers must anticipate the effects. For example, cornering requires more room; braking takes extra stopping distance, particularly downhill; and driving uphill may slow the vehicle down considerably (requiring four-way flashers to alert other drivers). Trailers may also affect the driver’s view. Ensure a clear view behind. Extra weight on the hitch and the size of load may require minor adjustment of mirrors. Keep load height low to improve your rear view. Extension side-mirrors may be necessary. Backing up requires a signaller if your view is at all obstructed.