The risks in charging an industrial battery?

The charging of lead-acid batteries can be hazardous. However, many workers may not see it that way since it is such a common activity in many workplaces. The two primary risks are from hydrogen gas formed when the battery is being charged and the sulfuric acid in the battery fluid.

For specific guidelines regarding large industrial batteries, check with the manufacturer for recommended safe work procedures.

Risk of an explosion?

When batteries are being recharged, they generate hydrogen gas that is explosive in certain concentrations in air (explosive limits are 4.1 to 72 percent hydrogen in air). The ventilation system can exchange an adequate amount of fresh air for the number of batteries being charged. This is essential to prevent an explosion. Also, no flame, burning cigarette, or other source of ignition should be permitted in the area.

Handling the batteries?

You can get a skin burn when handling lead-acid batteries. Sulfuric acid is the acid used in lead-acid batteries and it is corrosive. If a worker comes in contact with sulfuric acid when pouring it or when handling a leaky battery, it can burn and destroy the skin. It is corrosive to all other body tissues. For example, the eyes, respiratory tract, or digestive system can be harmed severely if a worker gets a splash in the eyes, inhales sulfuric acid mist or accidentally ingests sulfuric acid. As with any corrosive chemical, proper handling procedures must be followed to prevent contact with the liquid. This includes the wearing of gloves, face and eye protection, and aprons that are suitable for protecting you from accidental contact with sulfuric acid. As well, adequate first aid facilities, eye wash stations and emergency showers are necessary to reduce the severity of accidental contacts.

If contact with acid occurs, flush the area (eyes, skin) immediately for at least 30 minutes with clean, lukewarm, gently flowing water. Get medical help.

Hazards involved in batteries charging?

Depending on the metal alloy composition in lead-acid batteries, a battery being charged can generate two highly toxic by-products. One is arsine (arsenic hydride, AsH3) and the other is stibine (antimony hydride, SbH3). Generally, the air levels of these metal hydrides tend to remain well below the current occupational exposure limits during battery charging operations. However, their possible presence re-enforces the need for adequate ventilation systems.

How should industrial size batteries be handled?

Industrial batteries (e.g., forklifts or battery powered industrial trucks) may weigh up to 900 kg (2,000 lbs.) or more.

Workers must be trained in how to safely move batteries using appropriate equipment (e.g., specially equipped forklift, battery cart, conveyor, overhead hoist, etc.)

• Batteries must be securely placed and restrained.

• Use only the appropriate tools and follow safe work procedures.
  
  

Important to know about batteries?

Lead-acid batteries contain sulfuric acid and only trained and authorized personnel should handle them. When talking about lead-acid batteries, people usually call sulfuric acid "battery acid" or the "electrolyte". An electrolyte is general term used to describe a non-metallic substance like acids such as sulfuric acid or salts that can conduct electricity when dissolved in water.

• Use extreme care to avoid spilling or splashing the sulfuric acid solution. It can destroy clothing and burn the eyes and skin.

• Always wear splash-proof goggles and protective clothing (gloves and aprons). A face shield (with safety goggles) may also be necessary.

Batteries can weigh about 30 to 60 lb. so practice safe lifting and carrying procedures to prevent back injuries. Use a battery carrier to lift a battery, or place hands at opposite corners. Only change batteries if you have been trained to do so.ƒ

First aid if battery acid is splashed in my eyes or skin?

If the eyes are splashed with acid,

• Use an emergency eyewash/shower station if solution is splashed into the eyes.

• Immediately flush the contaminated eye(s) with clean, lukewarm, gently flowing water for at least 30 minutes, by the clock, while holding the eyelid(s) open.

• If irritation persists, repeat flushing. Neutral saline solution may be used as soon as it is available.

• DO NOT INTERRUPT FLUSHING. If necessary, keep the emergency vehicle waiting.

• Take care not to rinse contaminated water into the unaffected eye or onto the face.

• First aiders should avoid direct contact. Wear chemical protective gloves, if necessary.

• Quickly transport the victim to an emergency care facility.

If the skin is splashed with acid,

• As quickly as possible, flush the contaminated area with lukewarm, gently flowing water for at least 30 minutes, by the clock.

• If irritation persists, repeat flushing. DO NOT INTERRUPT FLUSHING. If necessary, keep emergency vehicle waiting.

• Under running water, remove contaminated clothing, shoes and leather goods (e.g., watchbands, belts). Discard contaminated clothing, shoes and leather goods.

• Transport the victim to an emergency care facility immediately.
  
  

Procedures for charging a battery:

• Charge batteries in a designated, well-ventilated area.

• Do not attempt to recharge a frozen or damaged battery.

• Follow the manufacturer's recommendations for charging rates, connections and vent plug adjustment. Properly maintained vent caps will reduce the chance of electrolyte spray.

• Unplug or turn the charger off before attaching or removing the clamp connections. Carefully attach the clamps in proper polarity to the battery.

• Rinse off batteries and clean terminals before recharging.

• Fill sulfuric acid (electrolyte) to the prescribed level before charging to reduce the possibility of the electrolyte heating up excessively. If water is added, use distilled water, not tap water.

• Turn off the charger before disconnecting the cables from the battery.

Safety tips to know when servicing batteries:

• Keep metal tools and other metallic objects away from batteries.

• Inspect for defective cables, loose connections, corrosion, cracked cases or covers, loose hold-downs and deformed or loose terminal posts.

• Replace worn or unserviceable parts.

• Tighten cable clamp nuts with the proper size wrench. Avoid subjecting battery terminals to excessive twisting forces.

• Use a cable puller to remove a cable clamp from the battery terminal.

• Remove corrosion on the terminal posts, hold-down tray and hold-down parts.

• Use a tapered brush to clean dirt from the battery terminals and the cable clamps.

• Use a battery carrier to lift a battery, or place hands at opposite corners.

• Do not lean over a battery.

Tips for handling battery solutions

• Pour concentrated acid slowly into water: Do NOT add water into acid - the water tends to sit on top of the heavier (more dense) acid. The water can become hot enough to spatter.

• Use nonmetallic containers and funnels.

• Recap any electrolyte container and store it in a safe place at floor level.

• Do not store acid in hot locations or in direct sunlight.

• Do not store electrolyte solution on shelves or any location where the container can overturn.

• Do not squeeze or puncture a container with a screwdriver or other instrument. The acid solution may splash on face, hands, or clothing.

• Do not fill a new battery with electrolyte solution while it is in the vehicle. Fill the battery while it is on the floor, before installation.
  
  

Procedure for boosting a positively grounded battery:

The vehicle is POSITIVELY grounded when the cable attached to the POSITIVE post of the "dead" battery is also attached to the engine block.

To connect cables:

• Clamp one end of the black cable onto the negative post of the "dead" battery.

• Clamp the other end of the black cable to the negative post of the booster battery.

• Clamp one end of the red cable onto the positive post of the booster battery.

• Clamp the other end of the red cable onto the engine block below and away from the "dead" battery.

• Start the engine of the booster vehicle, then the engine of the "dead" vehicle.

To disconnect cables:

• Remove the red positive clamp from the engine block of the vehicle with the "dead" battery.

• Remove the red positive clamp from the booster battery.

• Remove the black negative clamp from the booster battery.

• Remove the black negative clamp from the "dead" battery.

Relocatable power taps, often called power strips, portable outlets or surge suppressors, are defined by UL as “relocatable multiple outlet extensions of a branch circuit to supply … outlet receptacles for computers, audio and video equipment and other equipment." The need for multiple outlets came about during the arrival of computers and their associated equipment; such as the monitor, printer, scanner, and so on. They were designed for a high concentration of low-powered loads. Underwriter’s Laboratories is one of many Nationally Recognized Testing Laboratories (the OSHA reference is NRTLs) that test and approve products.

OSHA's standard at 29 CFR 1910.303(b)(2), Installation and use, requires that "Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling." Manufacturers and NRTLs determine the proper uses for power strips. For example, the UL Directory contains instructions that require UL-listed RPTs to be directly connected to a permanently installed branch circuit receptacle; they are not to be series-connected to other RPTs or connected to extension cords. UL also specifies that RPTs are not intended for use at construction sites and similar locations.

Power loads are addressed by 29 CFR §1910.304(b)(2), Outlet devices: "Outlet devices shall have an ampere rating not less than the load to be served."

Be sure to read and follow the instructions included with the product and not just the package instructions as these are sometimes geared towards marketing and sales, not safe usage.

RPTs are not designed for high powered leads such as refrigerators, microwaves, coffee pots, portable heaters, hair dryers or other appliances that generate heat or to be used outdoors.  Always directly connect the RPT to a permanently installed, grounded receptacle.  Avoid physical damage, exposure to water or wet locations, and use low-powered loads only.

An extension cord may look harmless but most extension cords are designed to carry 110 volts of electricity and 110 volts can kill. Extension cords are considered by both OSHA and the National Electric Code to be temporary wiring and certain rules apply to their usage. One of the most overlooked of all rules is the requirement to do a visual inspection of the cord before each use.

Extension cords are usually items that get lots of hard usage and are very susceptible to damage. This is one reason that OSHA requires a visual inspection of all flexible cords (including those on power tools) each day or before each use.

To provide an extra layer of protection, extension cords are required to be double-insulated. This means the conductors are covered with a colored insulating material and the jacket is an additional and separate layer of insulation. Never use a flat, appliance-type cord at work; the conductors of this flat cord are molded into the cord material and provide one layer of insulation.

A proper cord inspection includes an examination of the jacket for the entire length of the cord. Look for cuts in the jacket that expose the colors of the inner conductors, Once the integrity of the outer jacket is compromised, the cord cannot be repaired with tape or used in this condition. The cord may be cut and UL approved male and female plugs affixed to the ends.   Look for damaged strain relief, loose or missing prongs or ground pin, evidence of heat, such as smoke or melted insulation, pinching or discoloration.

Remove damaged cords from service until repaired or disposed of by a qualified person.

Extension cords are a safe and convenient way of providing power to portable equipment. Make sure that the thickness of the cord is the same, or even larger, than the cord of the tool being powered. You risk overloading the circuit if you plug one extension cord into another.

Never forget to use GFCI protection when using an extension cord. It can save your life!