Health and safety in the shop or garage
|Warning:||Safety is overlooked by many. The first rule of safety: Pay attention to what you're doing. Many accidents and injuries are caused by lack of attention to what is going on!|
 Eye protection
Corrective glasses and sunglasses are not an acceptable substitute for safety glasses. If wearing corrective glasses, then wear safety glasses designed to fit around them, or invest in a pair of prescription safety glasses. Standard safety glasses can be equipped with side shields, cups, or tinted lenses to offer additional protection.
In the United States, the national government standard for eye protection is ANSI Z-87.1 Make sure your safety glasses carry this designation.
Face shields and helmets are not in themselves protective eyewear. But, they are frequently used in conjunction with eye protectors. When grinding or when exposed to chemicals, use a full face shield over safety glasses or goggles.
While safety glasses and full-faced shields are acceptable in many situations, sometimes they are not enough. Safety glasses that completely fill the gap between the face and the lens are sometimes needed. Rust, hot metal grindings, and abrasives (like sand and dirt) can literally ricochet off your cheek, then bounce off the inside of the safety glasses and embed themselves into your eyes.
Your eyes heal very quickly. If you get slag embedded in your eye, it can easily "heal" over the slag, requiring surgery to remove it. See a doctor.
 Eye protection tips
- Eyebrows, hair, and hats can all hold debris that can get into and damage your eyes. Clean the "above the eyes" area on your body before removing your safety glasses.
- When showering after grinding, close your eyes while you wash your face thoroughly.
- Turn around the bill of your hat, because it can hold debris, or redirect it into your eye.
- Be careful of debris on anything that will be lifted over your eyes (like a ladder).
- When working under potential debris (like when working under a car), don't remove your safety glasses, for example, to wipe the dust off.
- Use the proper filter lens shade for the job. UV (ultraviolet) light can cause a number of vision problems, including deadly cancerous eyelid tumors and blindness.
 Arc flash
- Also known as "arc eyes", "flash burn", "snow blindness", "ultraviolet keratitis", or "corneal flash burn". It's analogous to a sunburn on your eyeballs.
- Avoid "blind" tack-welding, i.e. closing your eyes, blocking your eyes, or looking away when you tack.
- Take steps to ensure that nobody "walks in" on a welding job without eye protection, or they could get arc flash (i.e.: sign on the door).
- Don't weld with a white shirt on- white can be too reflective.
- Don't weld with "cool" sunglasses as protection. Being blind isn't cool.
 Symptoms of eye injury from welding flash
- Feels like you have sandpaper rubbing your eyeballs
- Bloodshot eyes
- Light sensitivity
- Excessive tearing
- Moderate to severe pain
- Can't close eyes (can't sleep)
 What about using potatoes or potato juice?
Ignore the old welder's tale of using a potato or potato juice. It's not sterile and could cause an infection. Instead, use eyewash from a first aid kit. See a doctor.
 What about using over-the-counter eyedrops?
Don't use topical anesthetic drops, because they can slow the healing of the cornea. However (ask your doctor), you may be advised to use over-the-counter lubricant eyedrops.
 When to see a doctor about arc flash
If you have worsening pain in your eyes, or your vision blurs or changes, you should see a doctor, preferably an ophthalmologist. Or, just go to an emergency room.
The doctor will examine your eye, typically with a slit lamp. You may receive some eyedrops to numb, dilate, or dye your eye to aid in the examination. Then, you'll probably get some eyedrops to take home, to help alleviate the pain or lubricate your eyes. In most cases, you should be recovered within a few days.
 Articles and tech info
- Safety glasses terms, types, and lens tint descriptions, from 4UrSafety.com
- Corneal flash burn, from eMedecineHealth.com
- Safety glasses glossary, from EquipDirect.com
 OSHA standards
- OSHA standard for eye and face protection
- OSHA guide listing proper filter lens shade number for different welding operations
 Hearing protection
Ear plugs and muffs are a must when working with loud tools like grinders, saws, routers, etc. People often overlook hearing protection because the damage is not immediately known and often occurs slowly over several years. Generally speaking, if you have to yell to be heard at arm's length distance, the noise is loud enough to cause hearing damage. If noise exposure causes ringing in the ears (tinnitus), some amount of damage has occurred. Once hearing has been impaired, there is no way to reverse the damage. Protect your hearing now and thank yourself later.
Wear ear plugs when welding overhead, to avoid getting slag in your ears.
- OSHA standard for occupational noise exposure
- Comparison of common sounds and their decibel level (pdf)
 Vibration protection
Prolonged use of vibrating tools can cause a condition known as Vibration White Finger, or Hand-Arm Vibration Syndrome (HAVS). HAVS can result in numbness, tingling, and pain -- and, in extreme cases, loss of fingers. Damage can come from extended use of a tool that vibrates slightly, as well as short use of a tool that vibrates heavily. The effect is cumulative over time. Exposure to vibration is measured in trigger time (the time that the tool operator is holding down the trigger of the tool), and acceleration amplitude of the tool. Trigger time is typically quoted in hours per day, and acceleration amplitude can be measured with an accelerometer or a special vibration analysis tool.
Anti-vibration gloves will help to protect against vibration. However, the best protection is to reduce exposure, or to use tools with a lower vibration rating.
 External resources
- Vibration safety guide -- includes vibration ratings for numerous tools.
- DeWalt vibration measurement, calculator, and legislation
- Reactec personal vibration measurement tools and solutions
- Vibration white finger Wikipedia entry
 Chemical handling and exposure
 MSDS (Material Safety Data Sheets)
Material Safety Data Sheets are summaries of the chemical properties of any material. Employers are generally required to have them available for any material they use, and manufacturers and distributors will often include them when they ship a product.
MSDS supply important info to people working with various materials in an occupational fashion. For example, an MSDS for paint is not highly pertinent to someone who uses a can of paint once a year, but is extremely important to someone who does this in a confined space, forty hours a week, for decades. Serious hobbyists who use materials regularly should consult the MSDS.
 Personal Protective Equipment (PPE)
Personal protective equipment should be chosen and worn correctly when working with various chemicals. Standard fare when dealing with a majority of chemicals includes safety goggles (often used with a face shield), apron, and protective gloves that protect the hands and forearms, and possibly even a respirator. PPE should be chosen carefully to ensure compatibility with the type of chemical being used.
Do not use thinners or solvents to clean your hands or other body parts. Solvents and thinners do soak through your skin and into your blood stream. Many solvents and thinners are very toxic and could cause severe irritations, sickness or death.
 Brake parts cleaner, welding, and phosgene poisoning
Phosgene, a deadly gas, may be produced when welding parts that have been cleaned with solvents containing chlorinated hydrocarbons, such as brake parts cleaner.
Phosgene was used during World War I as a chemical weapon. It is often not detectable, but may also smell like freshly mown grass or musty hay.
Phosgene is a combustion product of various common chlorinated solvents. It does not occur naturally. Ultraviolet radiation (like that created during welding) can convert chloroform into phosgene.
Phosgene is an irritant that damages the skin, eyes, nose, throat, and lungs. Symptoms of phosgene exposure include coughing, burning sensation in throat and eyes, watery eyes, blurred vision, shortness of breath, nausea, vomiting, and pulmonary edema. Delayed effects of phosgene exposure (up to 48 hours later) include difficulty breathing, coughing up white or pink fluid, low blood pressure, and heart failure. Long-term health effects of phosgene exposure can include chronic bronchitis and emphysema.
The effects of phosgene gas poisoning may not show up immediately, and may be cumulative over time, with multiple exposures.
By the time you can smell phosgene, you've already been exposed to a hazardous dose of it. Because of this, prolonged exposure to phosgene without intervention is possible. The OSHA permissible exposure limit to phosgene is 0.1 ppm (parts per million) averaged over an 8-hour workshift. Phosgene is considered immediately dangerous to life or health at 2 ppm. Because the odor detection threshold is 0.4 to 1.5 ppm, odor does not provide sufficient warning of harmful phosgene concentration in the air.
If you think you may have been exposed to phosgene gas, move outside or to fresh air. Phosgene gas is heavier than air, and will sink, so move to higher ground if possible. If your eyes are burning or your vision is blurred, rinse your eyes with fresh water for 10 to 15 minutes. Seek medical attention.
Those at risk of phosgene gas exposure may choose to wear phosgene detection badges.
 Further details on phosgene poisoning
- Wikipedia page on phosgene
- NIOSH pocket guide to phosgene
- CDC medical management guidelines for phosgene
- CDC facts about phosgene
- Anecdotal account of phosgene poisoning resulting from using brake cleaner to clean welded parts
 Battery acid
Automotive batteries contain "battery acid", or more formally, sulfuric acid. When handled improperly, sulfuric acid can cause blindness, burning, and death.
Batteries give off hydrogen gas during charging or when in operation in a vehicle. Avoid sources of combustion (flame, sparks) when in the vicinity of a battery to avoid an explosion.
 What do I do if I inhale, swallow, or splash acid in my eyes or skin?
If you get acid in your eyes, don't rub your eyes, or keep them closed. They need to be "irrigated" for at least half an hour. If possible, use an emergency eyewash/shower station.
Immediately flush the contaminated eye(s) with clean, lukewarm, gently flowing water for at least 30 minutes, while holding the eyelid(s) open.
If irritation persists, repeat flushing. Neutral saline solution (may be available from someone who wears contact lenses) 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. Flush any area of your body contacted by battery acid immediately and thoroughly.
As quickly as possible, flush the contaminated area with lukewarm, gently flowing water for at least 30 minutes. If irritation persists, repeat flushing. DO NOT INTERRUPT FLUSHING.
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 if conditions seem to warrant it of if in doubt.
If you ingest (i.e.: "swallow") acid, don't induce vomiting. If the victim is conscious, give 3 cups of milk or water. Don't ever give anything to an unconscious person. Seek medical attention.
If you inhale acid, get fresh air immediately. If breathing is difficult, give oxygen and seek medical attention.
 Don't use acid to clean concrete
Using acid to clean concrete can crumble and flake your concrete surface. Acid doesn't actually "clean" concrete -- it dissolves it. The acid soaks into the concrete, and will continue to damage it until it is neutralized. Instead of sulfuric or muriatic (hydrochloric) acid, or any other kind of acid, use a commercial product specifically designed for cleaning concrete.
Water will dilute acid to the point of being neutralized if enough water is used. Never add water to acid (remember the old chemistry class saying "do like you oughta, add acid to the water"). Always add acid slowly to water. In fact, sulfuric acid (and other strong acids) produces heat when it is introduced to water. The resulting exothermic reaction can almost instantly boil the water, blowing acid all over your body, leading to acid burns.
 Don't use battery acid to remove rust
Besides the fact that battery acid is extremely dangerous to handle, it can cause hydrogen embrittlement, which severely weakens metal.
 Medical and government references on sulfuric acid
Bondo, (a generic name for plastic body filler) was developed as a non-toxic replacement for lead. However, it still poses health risks. Gloves, mask, and sufficient ventilation are recommended when using Bondo. For more details, search the MSDS database at 3M.com.
 Skin protection
When handling hydrocarbon chemicals (oils, greases, solvents, paints, and thinners) use nitrile or latex gloves and/or skin protective barrier creams. Repeated and/or prolonged exposure can result in sensitization and possibly chronic skin or organ problems.
If using acids or any other harmful chemicals, use skin protection that's adequate for exposure to the substance in question. Not all rubber gloves are going to hold up to all chemicals, so use the MSDS or label instructions as a guide to proper protection.
 Respiratory protection
Respiratory protection is probably overlooked more often than eye and ear protection, yet is every bit as important. There are many jobs around the garage in which some form of respirator or mask should be used. These include but are not limited to: painting, welding, grinding, sandblasting, handling solvent tanks, and insulation handling (especially when it contains asbestos). Respirators are often found in two basic styles: full face and half face. These should be chosen based on the level of exposure that is anticipated. Generally speaking, a half face respirator should be sufficient for most at-home projects.
When spraying paint occasionally, it is recommended to at least use a half face respirator with a double filtration. The outer filter should stop dust particles, and the inner filter should be a charcoal type cartridge filter that absorbs fumes. This will greatly reduce your chances of inhaling harmful fumes and/or dust.
When spraying more than occasionally, the recommended protection is forced air or remote type system. Follow the MSDS and/or instructions that come with your material that you are working with. A study on the effectiveness of respirators in filtering isocyanates is available at the OSHA website. Two cartridges tested removed over 99% of isocyanates, and both are available from Amazon.com and local sources.
When you are done using your respirator, clean it and return it to a sealed container or sealed, "Ziploc"-type bag. The charcoal-type keeps working as long as there is air to work with.
Ventilation is often overlooked when taking on the tasks of grinding, welding, spraying.
When grinding, direct the material away from your face. Adequate ventilation is helpful to reduce fine particulates from being inhaled but the force of material thrown off of a grinding wheel or disc can be significant, so use eye, face and body protection and avoid breathing the dust.
When moving the air in an explosive environment (fine dust and chemical vapors), an explosion-proof motor must be employed.
 Lifting and handling heavy objects
Lifting and moving parts around the garage/shop can get to be a real pain (in the lower back). A quality, well built engine hoist will work well for moving heavy parts such as engines, transmissions and axles. An overhead hoist or gantry can work well for lifting a frame or even removing the body off a car.
It is important to use the right lifting gear for the job. Though this has been done more times than can be counted, using a 3/8" grade 3 bolt and a chain is not the safe way to move heavy items like an engine! Instead, use some sort of lifting fixture to lift the engine. Using lifting eyes or fixtures like those found on a factory installed engine works well. Combined with a high quality chain with hooks on each end, this will provide a much more secure way of lifting or transporting an engine.
Other heavy or awkward objects like axles or automotive bodies should be moved with high quality nylon (or even kevlar) straps that are free from cuts, frays, or tears. In order to prevent damage to the straps and possible loss or damage to the load, do not wrap the straps around sharp objects or edges. If wrapping around sharp edges cannot be avoided, then place a layer (or several layers) of material such as heavy cloth or canvas between the strap and the item being lifted.
 Jacking and jackstands
|Warning:||Never climb under a car that is supported by a jack without using jack stands, should the jack suddenly fail it could injure or kill. Also block tires front and back so they cannot move forward or backwards.|
Try to refrain from working under heavy objects. When this can't be avoided be sure to firmly support the load. When working under a vehicle that has to be jacked up, be sure to support the weight with jack stands or ramps designed to support the weight of the vehicle. Do not use the jack as the sole means of support. Always work on a solid, level surface and block the wheels to ensure the vehicle doesn't roll or fall off the supports. Make sure the jack/jack stands are designed to support the weight you will be raising. Unless on the road side, refrain from using a bumper jack as they are unstable and can push a car forward while jacking.
When setting jack stands or car lifts, make sure that one person sets the lift points. If two different people set them, it is likely that they will be in different spots, possibly making the object unstable.
When purchasing a jack or jack stands, price should not be the deciding factor. You want well built equipment that are rated for at least twice what you will ever use them for- after all, you are trusting your health and possibly your LIFE to them.
 Ladders and climbing
 Power equipment safety
 Leave gloves off when working with rotating equipment
Contrary to popular belief, it is best to leave the gloves off when working with items like bench grinders, drill presses, pumps or other rotating machinery. When gloves are worn, the risk of having your hand snagged by the rotating element increases as will the chance of losing a finger or hand. The glove gives the machine something to grab on to, and it will not let go of very easily. While a bare hand can still be drawn in, it is usually much easier to remove from the machine when this happens.
 Drill press safety
- Always clamp in your work piece. It could easily be ripped from your hand and spin around dangerously.
- A dead man's switch can make a drill press (or many other stationary power tools) considerably safer. If the work piece gets loose, all you need to do is lift up your foot, and the power to the tool is cut off.
 Air compressors
 Preventing explosion
Air compressors can explode violently, leading to severe injury or death. Fatigued or cracked compressor tanks should be discarded and replaced. If one area of a tank is cracked, then common sense suggests that other areas of the tank are also fatigued.
 Causes of air compressor tank explosions
The cumulative effects of vibration and expansion/contraction can cause metal fatigue. Also, moisture in the air line can cause rust to form inside the tank, leading to decomposition of the tank. In addition, use of non-OEM oil may cause carbon deposits which can ignite and lead to an internal explosion.
"When OEM oil is not used, studies have shown that the oil may leak past the seals and gaskets and form carbon deposits in the supply line. As the diameter of the supply line decreases because of the carbon deposits, the compressed air, which is already at a high temperature, will increase even more, to the point where it might be possible to ignite the carbon deposits. If this should happen, and a piece of ignited carbon gets into the air tank, it could cause an internal explosion."
 Anecdotal accounts of air compressor tank explosions
 Formal reports referencing air compressor tank explosions
 Standards and safety checklists
- OSHA standard for compressed gas and compressed air equipment
- Air compressor tank self-inspection checklist
 Aluminum grinding dust fireball
When aluminum grinding dust is mixed with steel or iron grinding dust, it can produce thermite, an explosive compound. Thoroughly clean aluminum dust from grinding machines before grinding iron or steel.
- HomeShopMachinist.net forum discussion
- Department of Energy "Lessons Learned" report on aluminum/steel dust thermite explosion
- Hotrodders forum threads
- Hotrodders Knowledge Base