Welding insurance, for the fire that starts after you leave
A welder's exposure is hot work: sparks and slag that land in something combustible and smolder, sometimes for hours. General liability answers for the burn, the customer's property, and the fire, and the fire that breaks out after the crew has packed up is a completed operations claim with its own limit on the form. No state licenses welding as a contractor trade, so the requirements that find you are OSHA's rules for employers, which draw a 35-foot line around the work and keep a fire watch for a half hour after it stops, and the terms in your customer's contract. The welder and cylinders are property that travels, the rig is commercial auto, and the first helper brings workers compensation.
Welding liability insurance: general liability and hot work
The NAIC sorts what a general liability policy answers for into four bins: someone hurt, someone else's property damaged, personal injury in the legal sense (slander, libel), and advertising that misleads (NAIC, Insure U: Small Business Insurance). The first two are a weld. Bodily injury is the plant employee who walks past the arc without a shield, or the customer's mechanic burned by a piece that was still hot. Property damage to others is the customer's equipment scorched by spatter, the hydraulic line cut through next to the bracket you were told to fix, and the fire. Those are the claims the form was written for.
The fire is the hard case, because of when it starts. Sparks and slag travel, land in insulation or sawdust or the cavity behind a wall, and smolder. The federal rule on fire prevention for welding requires a fire watch "for at least a half hour after completion of welding or cutting operations to detect and extinguish possible smoldering fires" (29 CFR 1910.252(a)(2)(iii)), which is the government's own statement that the fire can start after the arc stops. A fire that breaks out that night, after your crew is gone, is not an operations claim; it is a products-completed operations claim. In IRMI's definitions that hazard is one the general liability form ordinarily carries: it picks up liability from work done away from your own premises after the work is finished, and a job counts as finished once it is "completed as called for in a contract" or "put to its intended use" (IRMI, products-completed operations; IRMI, completed operations). That hazard carries its own aggregate on the form, separate from the general aggregate, and it is the first question to ask about a welding policy: is products-completed operations included, and at what limit. What the form leaves out is on the NAIC's list too: professional errors and omissions, which here is the allegation that you chose the wrong procedure or filler for the joint rather than that the joint burned something. The HVAC contractor insurance page shows what a state does when it writes a separate completed operations floor into a license; Texas does that for air conditioning contractors and not for welders. The plumbing contractor insurance page reads the same completed operations hazard for water instead of fire.
Welding insurance requirements: no license, OSHA's hot work rules, and the contract
No state licenses welding as a contractor trade. Texas licenses named trades through the Department of Licensing and Regulation, electricians and air conditioning contractors among them, and its list of programs has no welding entry (TDLR, licensed programs); how Texas handles the trades it does license is on the Texas contractor insurance hub. So there is no board, no license floor, and no statutory minimum. What reaches a welding business instead is a federal rule written to employers, and a customer's contract written to whoever wants onto the site.
The OSHA rules, read as an underwriter reads them. OSHA addresses welding, cutting, and brazing in 1910 Subpart Q for general industry and 1926 Subpart J for construction (OSHA, Welding, Cutting, and Brazing: Standards). The general industry rule sets the order of operations: "If the object to be welded or cut cannot readily be moved, all movable fire hazards in the vicinity shall be taken to a safe place"; if neither the object nor the hazards can be moved, "guards shall be used to confine the heat, sparks, and slag"; and if neither of those can be done, "welding and cutting shall not be performed" (29 CFR 1910.252(a)(1)). A fire watcher is required where a more than minor fire might develop, including where there is "Appreciable combustible material, in building construction or contents, closer than 35 feet (10.7 m) to the point of operation," and the watch runs at least a half hour after the work stops (1910.252(a)(2)(iii)). The supervisor "Shall secure authorization for the cutting or welding operations from the designated management representative" (1910.252(a)(2)(xiv)), which is the closest the federal rule comes to a hot work permit, and "No welding, cutting, or other hot work shall be performed on used drums, barrels, tanks or other containers until they have been cleaned so thoroughly as to make absolutely certain that there are no flammable materials present" (1910.252(a)(3)(i)). The construction rule says the same things in its own words: move the work or the hazards, take "positive means" to confine heat, sparks, and slag, keep "Suitable fire extinguishing equipment" immediately available, assign "additional personnel" to guard against fire during the work "and for a sufficient period of time after completion," and take the same precautions on the far side of a wall, floor, or ceiling (29 CFR 1926.352). The 35 feet and the half hour are the general industry rule's figures; the construction rule prints neither. Both are written to employers and say nothing to a solo welder about his own safety, and both become underwriting questions the day there is a helper. The consensus standard behind all of this is NFPA 51B, Standard for Fire Prevention During Welding, Cutting, and Other Hot Work (NFPA 51B), which is a published standard rather than a rule. What it requires is not summarized here; NFPA publishes the text.
The contract is the requirement you will actually meet. A general contractor, a refinery, or a plant will want a certificate of insurance before your truck is on the site, and will often want the hot work procedure written out, the fire watch named, and the site's own permit signed. A builders risk policy on a construction project is the reason: IRMI lists "cutting, and welding" among the protective safeguards builders risk underwriters have imposed on projects (IRMI, Builders Risk: Protective Safeguards and Conditions Update), and the builders risk insurance page explains whose policy that is and why the GC passes its conditions down to you. The "bonded and insured" line that shows up in the same paperwork is explained on the bonded and insured guide.
Welding equipment insurance: the welder, the leads, and the cylinders
Business property coverage can extend to equipment and supplies whether owned or leased (NAIC), and a welder's property is rarely at an address. The engine-drive welder, the leads, the torch outfit and regulators, the cylinders, the grinders, and the consumables ride on the truck and sit at the job or outside a motel. Agents write this line as an equipment floater rather than as property at a fixed location; ask how a unit stolen off the bed overnight is treated, whether cylinders are covered as equipment or excluded as stock, and whether the shop's fixed equipment and the truck's equipment are on the same schedule.
Commercial auto for the rig
Own or lease a vehicle for the business and the NAIC's guidance is plain: the personal auto policy can exclude business use, and a commercial form is the one that extends to rented vehicles and to an employee's own truck when it is driven for you (NAIC). The rig is a truck before it is anything else: a pickup or flatbed carrying an engine-drive welder, a rack of cylinders, and several hundred pounds of leads and steel, which handles differently loaded than empty. It belongs on a commercial auto schedule with its use described, and the equipment on the bed belongs on the property schedule above, not on the auto policy. The helper who meets you at the job in his own truck is driving for you; hired and non-owned auto liability is the line that answers for that vehicle. Operators who run several rigs, or who haul under a motor carrier authority, are on the trucking side of insurance and should be read there.
Workers compensation for a welding crew
Workers compensation is mandatory for employers in nearly every state, as the NAIC puts it (NAIC). The Texas Department of Insurance describes how the premium is built: payroll is split by classification, each class carries a rate per $100 of payroll, and an experience modifier adjusts for the employer's own losses (TDI, workers compensation rate guide). Contract welding has a class of its own in New York, where the rating board's phraseology for code 3365 is "Welding or Cutting – NOC – All Operations to Completion & Drivers," applied to "employers engaged in all types of contract welding or cutting operations which are not otherwise classified" in "both shop and/or outside work" (NYCIRB, Class 3365). New York's bureau wrote that phraseology; another state's bureau may class the same shop differently, and no rate appears on this page.
The crew's hazard is the fume as much as the burn. OSHA's own fact sheet: "The welding process produces visible smoke that contains harmful metal fume and gas by-products," including manganese, chromium, nickel, lead, and cadmium; "Prolonged exposure to welding fume may cause lung damage and various types of cancer"; shielding gases "displace oxygen in the air and can lead to suffocation, particularly when welding in confined or enclosed spaces"; and chromium in stainless and some consumables "is converted to its hexavalent state, Cr(VI), during the welding process," which OSHA regulates separately (OSHA, Controlling Hazardous Fume and Gases during Welding, FS-3647). The hazard communication standard requires employers to provide information and training on the hazardous chemicals their workers are exposed to (29 CFR 1910.1200), and welding consumables are on that list. Whether the helper is an employee turns on the right to control the work, not on how you pay him; for the IRS an employee "works at the control and direction of another" (IRS Publication 4902). Texas lets a private employer opt out; its Department of Insurance states that workers compensation "is not required in most cases" (TDI, employer resources); the filing a non-subscriber makes and the defenses it gives up are on the Texas hub.
Welding insurance cost: what moves the premium
No figure appears here, because any number would be a guess about a shop we have not seen; what follows is what an underwriter weighs. Where you weld leads: a shop with fixed equipment and a concrete floor reads differently from a field job on someone else's site. What you weld comes next. Structural steel, ornamental and repair work, pipe, and oilfield work each read differently, and pipe and oilfield read as a higher hazard because of pressure, product, and where the work is. How high and how enclosed: work from a lift, and work inside a tank or vessel, each carry their own rules and their own price. Revenue, because the liability premium is often rated on it, and payroll, because the workers compensation premium is built on it. The vehicles on the schedule and what rides on them. Loss history, which reaches the workers compensation premium through the experience modifier and the liability premium through the file. Your state, and whether workers compensation is elective there. The word "welding" alone gets priced against confined-space work inside a tank. What you actually weld, where you weld it, and a written hot work procedure are what separate your file from that. The electrician insurance page is the contrast worth reading: a trade that also starts fires, but one the state licenses and writes an insurance floor for.
Your state's rules
No state trade license, a federal rule written to employers, and an elective workers compensation system with real trade-offs. The Texas hub carries the state's structure; welding pages for other states follow as their rules are read.
Or start at the overview for how the whole contractor set fits together.