Met Guard Boots: Internal vs External Guards, the Mt Test, and Who Pays

The metatarsal test uses the same striker energy as the toe impact test, but lands somewhere else and is judged differently. Thorogood's summary of F2413-18 gives the numbers. A 50 lb weight delivers a nominal 75 foot-pounds of energy (101.7 J) at a point 3.5 inches back from the toe (3.375 in on women's sizes). Afterwards the guard must still leave 1.0 inch of clearance over the foot form on men's sizes, or 0.937 inch on women's. The toe impact test uses the same 75 ft-lbf on the toe cap, and the cap must keep 0.500 inch of clearance (0.468 inch women's). Both numbers are energy in foot-pounds. Neither is the weight of the striker.

ASTM also requires toe protection on any boot with an Mt rating, so every met guard boot is a safety-toe boot first. On the label, Mt shows up in different forms depending on the edition and the maker. KEEN prints 'MT/75' in the older style, alongside 'I/75 C/75'. Wolverine prints 'Mt'. Timberland PRO's listing describes it in a sentence instead of a code line. All of them refer to the same test.

What the test doesn't cover is just as useful to know. It doesn't rate compression across the instep (the C code applies to the toe cap). It doesn't test the guard after it has been crushed or bent. And it doesn't cover the ankle or shin. CCOHS advises replacing footwear after a significant impact or puncture, because damage may not be visible, and a met guard that has taken a hit is no exception.

Both designs can carry the same Mt rating, because the test sets a minimum, not a design. The difference is where the guard sits and what that does to your day. An external guard is a hard, padded flap fixed to the outside of the boot over the laces and instep, like the boots in the photo above. An internal guard is built into the upper under the leather, so the boot looks almost normal. KEEN's Evanston uses a material it describes as flexible that 'hardens and protects upon direct impact'.

For welders and anyone working near hot spatter, the external flap has a side benefit: it covers the laces. For anyone who kneels, climbs ladders or drives, the internal guard usually suits better because there is no flap to snag or press into the shin. Strap-on guards are a third option. They are a separate product that buckles over an ordinary safety-toe boot, and they are what many employers issue. If you use one, check which standard its own maker cites, because the boot's label doesn't cover an add-on.

A few common mistakes. A boot with a 'met guard look' but no Mt line is not rated. A soft-toe boot with a strap-on guard is missing the toe protection that Mt boots must have. Some makers don't say which type their guard is: Wolverine calls the Raider's a 'TPU Met-Guard' on the upper and stops there. When your site requires one style, confirm it on the boot itself before buying.

Your employer's hazard assessment decides, and federal OSHA doesn't publish a list of jobs that require Mt. The hazard it targets is clear enough: heavy objects that can fall on or strike the top of the foot, not just the toes. It shows up where long, heavy loads are handled close to the feet, such as foundries, steel mills and heavy fabrication. In our finder, the 'Foundry / steel mill / heavy materials' preset adds the top-of-foot hazard to dropped objects and rolling loads for that reason.

General construction usually doesn't call for it, and that question comes up a lot. An r/Construction thread title asks it plainly. The answer depends on your tasks. A framer or finisher usually needs I/C and often PR. A crew setting steel or handling heavy pipe may be told to add Mt. If you are unsure, ask the safety lead what the hazard assessment says, not what other crews wear.

If you need Mt only some of the time, a strap-on guard over your normal boots can be the practical answer, especially when your employer issues them. If you need it every shift, built-in guards are less to manage and can't be left in the truck.

This is where most people get it wrong. Under 29 CFR 1910.132(h)(1), employers must provide required PPE at no cost, with listed exceptions. Plain safety-toe boots are one exception: (h)(2) says employers don't have to pay for 'non-specialty safety-toe protective footwear' that workers may wear off the job. Metatarsal guards are not in that exception. If your hazard assessment requires met protection, your employer has to provide it.

The catch is (h)(3), quoted in full: 'When the employer provides metatarsal guards and allows the employee, at his or her request, to use shoes or boots with built-in metatarsal protection, the employer is not required to reimburse the employee for the shoes or boots.' So if your employer hands out strap-on guards and you would rather wear met guard boots, you can usually choose that, but you pay. Construction has the same rule in 29 CFR 1926.95(d)(3).

Ask two questions before you buy. Does your employer issue met guards, strap-on or built-in, for your job? And does it run a boot allowance or voucher program that covers met guard boots anyway? Some employers do as a matter of policy, even where the rule doesn't require it.

Our catalogue tracks every boot by the codes its maker publishes, and only three carry Mt today. That's partly because met guard boots are a narrow category, and partly because we include only boots whose Mt rating we could read on a maker or brand page. The table below shows how they differ on the things buyers ask about: guard type, toe, EH, puncture and waterproofing.

There are clear gaps. None of the three is a women's boot. An r/WorkBoots thread title is a woman asking how to find 'women's steel toe metatarsal/met guard work boots on Amazon', and our catalogue can't answer it yet. Women can try a men's size with the help of our size chart, but the Mt test's clearance point is set lower for women's sizes (3.375 in from the toe) for a reason. A men's boot puts the guard where a man's foot would be. Also, only the Endurance lists puncture protection, and only the KEEN and Wolverine list EH. If you need Mt, PR and EH together, none of these three covers all three, so widen your search and check labels.

On fit: a guard can take up room over the instep, and an internal guard can make the throat of the boot feel stiffer. Size them in the afternoon with your work socks on, and make sure you can flex your foot fully without the guard digging into the top. Fitting the PPE to the worker is the employer's job too: 1910.132(d)(1)(iii) requires PPE 'that properly fits each affected employee'.