It only takes a moment to ensure your safety.
By Gustavo A. Gonzalez
Equipment lockout has been the No. 5 violation on the OSHA Top Ten Violations list for the past three years. It is a statistic that suggests many employers are either not aware of or are not paying attention to this important piece of legislation.
It is a common misconception that the term “lockout” refers only to the de-energization of electrical equipment. But as the name of the OSHA regulation itself implies (OSHA Standard 1910.147, Control of Hazardous Energy, and covered under Canadian regulations as well), it is the control of any source of hazardous energy such as electrical, mechanical, hydraulic, pneumatic and thermal energies. These energy sources have their own unique dangers and require special precautions when maintaining them.
Electrical Energy. Contact with electrical energy can cause burns, shocks and electrocution.
Mechanical Energy. There are two kinds of mechanical energy hazards: kinetic, which is the energy of moving machinery; and potential, which is the energy stored in parts of machinery such as pistons, springs and hoses. If these energies are not isolated and dissipated before performing work on any piece of equipment, there is a great danger for injuries (amputations, lacerations, entrapment) and possibly death.
Hydraulic Energy. Hydraulic energy is the energy of liquids under pressure. The sudden release of this energy could cause severe burns, as in the case of hot hydraulic oil, ejection of parts or sudden movement of machine parts, all of which can result in severe injuries.
Pneumatic Energy. Pneumatic energy is the energy of gases under pressure, including air. The uncontrolled release of these substances will cause injuries in most cases. For example, imagine the damage a broken air hose swinging uncontrollably in the air may cause.
Thermal Energy. The energy of heat and cold is thermal energy. Hot fluids or hot equipment parts can burn you; the same is true of cold fluids as in the case of liquefied petroleum gas (LPG) used in forklifts.
Safety professionals constantly hear about fatal accidents due to improper procedures – or perhaps the lack of procedures – involving lockouts.
In the precast industry, numerous pieces of equipment and machinery could cause severe injury or even death if proper lockout procedures are not implemented before working with, servicing or cleaning them.
Molds, aggregate bins, conveyors, shears, benders, packers and mixers are some of the pieces of equipment in a precast plant that require lockout before any employee attempts to perform maintenance or cleaning on the equipment. Most of these require multiple lockouts, as they are usually operated by air, hydraulics and electricity.
The regulations require that all individuals who perform a lockout must be properly trained in the procedures. They also require that all employees affected by the lockout be trained in recognizing when control procedures are being used and the importance of not removing any lockout equipment.
A lockout must be implemented any time safety guards or safety devices are removed or disconnected that may result in employee exposure. Lockouts are also necessary when employees are required to place any part of their bodies in direct contact with the point of operation of the machine or in any danger zone within a machine operating cycle, such as going inside a mixer for cleaning.
In addition to training, the regulations also require the employer to establish a program consisting of energy control procedures and periodic inspections or audits.
These energy control procedures must include:
• A specific statement of the intended use of the procedure
• Specific steps for shutting down, isolating, blocking and securing all machines or equipment to control hazardous energy
• Specific steps for the placement, removal and transfer of lockout devices and the responsibility for them
• Specific requirements for testing a machine or equipment to determine and verify the effectiveness of lockout devices and other energy control measures
• A written program that will be disseminated to employees
Under the periodic inspections or audits, the employer must conduct an inspection at least annually to ensure that the procedures and requirements of this standard are being followed. This inspection will include a review between the inspector and the authorized employee to ascertain that the procedures are being followed. It will also help determine whether the procedures are effective as written. This inspection shall be certified by the employer.
Another procedure allowed under regulation is “tagout” whereby a tag is attached to the isolating device indicating that the equipment is disconnected from its energy source. This procedure can be used only if the energy source cannot be locked out. Tagout is not as safe as a complete lockout and may evoke a false sense of security. Most precast plants use a complete lockout program, however.
Other isolation devices commonly used with lockouts may include:
• Placing a block of wood under the forks of a forklift while working on it
• Installing chains to hold the head of a press while working under it with the hydraulic unit off
• Removing the battery of a vehicle
• Closing a valve and locking it with a chain and lock
• Removing a piece of pipe to isolate the system
In a precast plant the mixer is perhaps the most dangerous piece of equipment, because somebody has to go inside it every day for cleaning and therefore the risk increases. Some newer mixers incorporate a pressure wash that eliminates some of these hazards, but in most plants the mixer must be cleaned manually. Remember, only authorized and trained employees can go inside a mixer, and then only after they install all lockouts, pocket the keys and ensure that it cannot start up.
Some plants wisely use three lockouts on the mixer: one in the control panel, one in the motor disconnect and one in the main circuit breaker. Even with these precautions in place, cleaning the mixer is a dangerous operation and should be treated as such.
Conveyors must also be locked out when performing work on or around them. Most of them start automatically without any warning, and therefore it is important to eliminate all sources of pneumatic and electric energy.
Two major causes of accidents from machines can be attributed to overconfidence and the “quick fix.” Overconfidence is based on the wrong belief that because the employee has done something over and over again without a problem, nothing bad will ever happen. Most of the time, this dangerous concept is based on lack of knowledge, lack of supervision or lack of training. Remember: All it takes is one time or one split second for someone to get killed or severely injured. The quick fix, as the name implies, happens when employees do something to the machinery without following the proper procedures because it may take too long. Either way, the employees must understand that they are placing themselves in a highly hazardous situation and the consequences could be fatal if something should go wrong.
The main causes of lockout injuries are failure to stop equipment, failure to disconnect equipment from the power source, and accidental restarting or failure to clear work areas before restarting the equipment. According to OSHA, compliance with the Control of Hazardous Energy standard could prevent an estimated 120 fatalities and 50,000 injuries each year.
NIOSH publication 99.110 lists some accidents as a consequence of not following proper lockout procedures in various industries:
• A 25-year-old male worker at a concrete pipe manufacturing facility died from injuries he received while cleaning a ribbon-type concrete mixer.
• A 38-year-old worker at a county sanitary landfill died after falling into a large trash compactor used to bale cardboard for recycling.
• A 33-year-old janitorial worker died after he was trapped inside a dryer at a hospital laundry while cleaning plastic debris from the inside of the dryer drum.
All of these accidents could have been prevented had the proper lockout procedures been followed.
As an employee working in and around equipment, remember these basic rules:
1. If you are not an authorized, trained employee, do not attempt to lock out or isolate equipment from its energy source.
2. If the equipment is locked, do not try to remove the lock or start the equipment.
3. If any part of your body is in a danger zone, the equipment must be locked in accordance with proper procedures.
4. Shutting down the equipment with the on-off switch or closing a valve is not considered a lockout.
5. Do not remove any guards or any safety devices if the equipment is not locked out.
6. If you perform a lockout, keep the key with you at all times.
7. Do not attempt any quick fix; lock out the equipment.
8. Understand and become familiar with your plant’s lockout program.
9. Do not operate equipment without safety devices in place.
10. If you do not know or have any doubts about the procedures to follow, talk to your supervisor.
Failure to isolate energy sources can and will kill you. Think before you act; a moment of prevention is better than a lifetime of pain and suffering.
Gustavo Gonzalez has nearly 20 years of experience in the precast concrete industry. He has a bachelor’s degree in Industrial Engineering Technology from Florida International University and is a former precast concrete plant manager. He currently serves as an instructor for the National Safety Council and the National Precast Concrete Association.