Oxy-Acetylene Cutting Safety in Agriculture OSHA Standard 1910.253 Produced by Idaho State University Office of Workforce Training

“This material was produced under grant SH22228SH1 from the Occupational Safety and Health Administration, U.S. Department of Labor. It does not necessarily reflect the views or policies of the U.S. Department of Labor, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.”

OSHA and Agriculture Not all farms fall under OSHA jurisdiction Who is exempt: Farms that only employ immediate family members or farms with 10 employees or less (this exemption, however, does not apply if the operation has maintained a temporary labor camp within the last twelve months, OSHA directive CPL 02-00-51) Additional state guidelines may apply

Personal Protective Equipment for Agriculture Applications (1 of 2) Cotton pants (no polyester coveralls) Cotton shirt, long sleeve, button up collar loose enough to button (no oil in fabric) Gauntlet style leather gloves ANSI approved safety glasses Welding cap, ear plugs Tapper’s jacket, leather jacket, or leather sleeves

PPE (2 of 2) Leather boots above the ankle MSHA approved respirator if applicable Housekeeping: flame circle, no combustibles in cutting area, HAZMAT cabinet, clean up junk or debris Have an A, B, C rated fire extinguisher present Always have a partner, use the buddy system Cutting glasses with a minimum shade #5 lens

Fittings Brass construction Left hand threads for acetylene/notch Right hand threads for oxygen/ no notch Use no thread tape or pipe “dope” Never repair hose damage with tape or other materials Use “backup” wrench for a snug fit Check for leaks with soapy water

Fittings

Gas hoses Red: acetylene Green: oxygen Protect from heat, sparks, friction, or damage Check for leaks with soapy water Protect from weather Use flashback arrestors, check valves

Cylinders: High Pressure Gas (1 of 2) One piece construction, formed armor plate Color of cylinder means nothing ONLY the label will identify the gas OSHA 1910.253(b) (1) (ii) Valve is double seated: open all the way Inspect cylinder for arc strikes, grinder marks, or other damage. NEVER use cylinder as a roller or set heavy objects on. OSHA 1910.253 (b) (5) (ii) (I)

Read the Label OSHA 1910.253.(a) (2)

High Pressure Cylinders, cont. Two person lift Use a cart to move on concrete, rough, or flat surfaces Cylinders MUST be chained in cart prior to movement Gauges need protective covers or be removed and safely stored prior to transport Cart and cylinders must be secured to move in a vehicle High pressure cylinders need hydro-testing every 10 years—dates are stamped in to cylinder Bursting disk on stem, safety device

How to Transport OSHA 1910.253.(b) (5) (iii) (A)

Gauges (1 of 3) Brass construction Delicate, yet rugged instruments Left handed/right handed Oxygen: green; Acetylene: red Tighten gauge with 10 or 12” wrench Connect hoses and torch body with cutting head Blow out stem by (cracking) valve briefly prior to securing gauges with cylinders

Brass Oxygen Gauge

Gauges (2 of 3) Back adjusting knob or “T” handle out prior to opening cylinder very gently, slowly Stand to side of cylinder, use both hands to grasp valve handle, and gently open cylinder Listen for gradual release and flow of product through gauge into hose Once pressure has stabilized, turn adjusting knob or handle inward to set working pressure

Adjusting Screw

Gauges (3 of 3) Gauge has two readings: one is working pressure and the other is what remains in the cylinder Never use oil on gauges: NEVER Protect gauges from damage during use and transportation Never try to repair gauges yourself--settings need calibration Never use compressed oxygen to blow dust out of clothes

A Little Oil Goes a Long Way

Low Pressure Acetylene (1 of 3) Two piece construction, welded mild steel Full of monolithic material (absorbent) for safety (looks like kitty litter) see example Cylinder contains acetone to increase absorption and stabilization of acetylene Avoid laying cylinder down Safety plugs (e.g., fuse and melt) Single seated valve: open ¼ turn

Low Pressure Acetylene, cont. (2 of 3) NEVER set regulator above 15 psi OSHA 1910.253 (a) (2) Color of bottle means nothing: read label Acetylene is sold by weight Acetylene evolves off from liquid mixture in cylinder. Acetone absorbs 50 times its own weight in acetylene and stabilizes it

Low Pressure Acetylene, cont. Never pick up any cylinder by the cap (e.g., hook on a chain with bucket loader) Secure cylinder with chains in bottle cart or transport in upright position, chained/secured to truck frame or rack. OSHA 1910.253.(c)(5)(vi) Inspect cylinder for dents, scratches, or damage Open valve on cylinder only ¼ turn in case of fire

Cutting Tips for Agriculture Repair Every torch has a tip: cutting tips have pre-heat holes and a cutting jet orifice Tips should be cleaned prior to use Flat file for facing the tip Tip drills or tip cleaners for orifice(s) Tips should never touch the metal or be used to tap with

Lighting the Torch in the AG Shop or in the Field (1 of 2) Create a “flame circle” wear all PPE OSHA 1910.253 (b) (5) (ii) (I) Remove all unneeded personnel and flammable materials from the area Adjust or re-check gauge settings Turn/open acetylene knob on torch handle Use a striker only to ignite acetylene gas, adjust flame: no cigarettes, lighter, or arc welder Turn/open oxygen knob on torch handle Adjust flame to neutral: re-check gauges

Lighting the Torch (2 of 2) Neutral flame should not produce heavy black smoke, carburizing and oxidizing flames have other purposes (e.g., brazing, hard-facing) Feather end should be apparent Depress oxygen cutting valve and listen for a rushing, jet like sound Pre-heat orifices should all be the same length You are now ready to cut

Cutting Carbon Steel in Agricultural Applications Select a cutting tip for suited to metal thickness Light torch, obtain neutral flame Hold torch tip an 1/8” to 3/16” from metal Wait until metal begins to puddle or melt Depress oxygen cutting lever Wait for oxygen stream to push molten metal through, creating “kerf” Look at puddle and listen to adjust cut speed

Helpful Cutting Techniques Tip must be clean and proper size Acetylene and oxygen levels must be set with flame lit (working pressures) Metal needs to be as clean as possible Neutral flame is a must: carburizing/oxidizing won’t produce a good cut A good cut should not require grinding

Cutting Safety in the Shop or Breakdown in the Field Have a fire watch NEVER cut into a barrel, cylinder, or container without knowing what was or is in it Zinc coating (galvanized) produces toxic fumes Protect hoses, gauges, cylinders, yourself, and your equipment while cutting

Shutting down Turn off acetylene Turn off oxygen Shut off both cylinder valves Back adjusting screw “T” out on both cylinders Bleed both lines Roll up hoses Store cart or secure cylinders with covers

Additional Safety Concerns Store gauges, hoses, and cutting equipment in a safe, clean place. Always secure bottles (with caps on) for transport If you must lay acetylene bottle down in a truck for transport, it must be stood up an equal amount of time for acetone to settle Absolutely no combustibles in the vicinity of cut

Questions? Review Practice setting up, cutting, shutting down torch Hands on demonstration

Evaluation Produced by Idaho State University Office of Workforce Training