Motorcycle Helmet Standards Explained: DOT, ECE 22.05 & Snell

DOT label layout you’ll see on helmets conforming to the DOT helmet certification and labeling standards effective in May 2013

A Heads Up on DOT, ECE 22.05 & Snell Motorcycle Helmet Standards

Implementation of the latest revision to DOT helmet standards looms in May, 2013, so here’s a handy look at the three most common helmet performance standards.

Buying a helmet may make you wonder about the various helmet safety certifications and changes that go into effect in May 2013 for the DOT helmet standard may make you wonder even more.

There are more than the three standards that we’ll cover here, but these are the ones you are most likely to see: DOT, ECE 22.05 and Snell.

We don’t assume that one standard is superior to any of the others; rather the purpose is to show how the standards compare and where they apply. These motorcycle-helmet standards are not mutually exclusive; some helmets are certified to multiple standards.

Following is an explanation of each helmet standard.

DOT Helmet Standard:  

This stands for “Department of Transportation,” (not “doin’ our thang”) but the standard is FMVSS 218, the Federal Motor Vehicle Safety Standard #218, Motorcycle Helmets, and it is applicable to helmets sold in the U.S. for on-road use.

That’s correct — the National Highway Safety Administration (NHTSA) enforcement authority of the DOT certification requirement applies to helmets intended for on-road use, though using a certified helmet for off-road purposes or in competition is certainly a good idea.

NHTSA does not test helmets against the DOT standards before they can claim DOT certification; rather, each helmet manufacturer marketing their helmets for road use in the U.S. must test and self-certify the models they want to sell and then permanently affix the “DOT” emblem signifying compliance with FMVSS 218.

NHTSA enforces the standard by acquiring random samples of the product and sending them to an independent testing lab to verify compliance. Penalties to manufacturers for marketing non-compliant products can be steep—up to $5,000 per helmet.

FMVSS 218 sets standards in three areas of helmet performance: impact attenuation, basically energy absorption; penetration resistance; and finally the retention system effectiveness, and there are new product labeling requirements.

The standard also requires peripheral vision to be not less than 105° from the helmet midline.  Projections from the surface of the helmet (snaps, rivets, etc.) may not exceed 5 mm.

The impact test measures acceleration of a headform inside the helmet when it is dropped from a fixed height onto a spherical and flat surfaced anvil. The standard allows a peak acceleration energy of 400 G (G being “gravity constant” or an acceleration value of ft. per second x seconds).

The penetration test involves dropping a piercing test striker onto the helmet from a fixed height. The striker must not penetrate deep enough to contact the headform.

The retention system test involves placing the helmet’s retention straps under load in tension.  For this test the load is progressive; first a load of 22.7 kg (49.9 lb.) is applied for 30 seconds, then it is increased to 136 kg (299.2 lb.) for 120 seconds, with measurement of the stretch or displacement of a fixed point on the retention strap from the apex of the helmet.
Some new standards in FMVSS 218 will go into effect in May 2013.

As a result of confusion over the specifications in the test procedures for impact attenuation and the retention system, new test procedures have been put into place.

The apparatus for testing a helmet retention system under DOT (FMVSS 218) standards.

Those changes won’t be noticeable to the buyer—but one change will be: the DOT label that must appear on the helmet. Under the new standard, the simple “DOT” sticker of old won’t cut it.

In an effort to make counterfeit labeling of non-compliant helmets more difficult and legally risky to those who do it, the DOT label displayed on the back of the helmet must now include, in order from top to bottom:

The manufacturer’s name

  • Model number or name
  • “DOT” below the manufacturer’s name
  • “FMVSS 218” centered below DOT
  • The word “Certified” below FMVSS 218

For additional information, visit the National Highway Safety Administration.

The old DOT certification label had different looks from different manufacturers.  Note that these helmets have DOT and ECE 22.05, or DOT and Snell certifications showing that the standards aren’t necessarily mutually exclusive.  That will still be true with the new DOT standards in effect.

ECE 22.05 Helmet Standard:  

ECE stands for “Economic Commission for Europe,” which was created under a United Nations agreement in 1958.  The 22.05 part refers to the specific regulation that the standards for testing are described in.

The ECE standard, which is accepted in 47 countries, is similar to the DOT standard in several ways, for example: like the DOT standard, peripheral vision through an arc of 105° from the helmet midline is required.  Also, environmental conditioning of helmets to be tested is required similar to the DOT standard and certain labeling requirements apply, as well.

Impact absorption testing is performed in a manner very similar to the DOT standard, involving a drop test from a fixed height on a steel anvil with a headform fitted inside to measure the energy transmitted.  Peak acceleration energy at the headform allowed to pass the test is 275 G.  Impact absorption and rotational forces are also tested at points where any surfaces or parts project from the shell of the helmet.

The retention system is tested with a free-fall drop test of a 10 kg (22.0 lb) weight from a height of .75m (29.5 in.) attached to the fastened chin strap.  No more than 35mm (1.37 in.) displacement of the attachment point is allowed.

The chin strap buckle system is also tested for slippage under load, and the strap material itself is tested for abrasion resistance and tension failure load (which cannot be less than 3kN or 674.4 lb.).  There are also tests for ease of release and durability of quick-release buckle systems.

There are some areas where the DOT and ECE standards differ, for example: The surface of the helmet is tested for abrasion resistance—but in this test the performance standard requires that the helmet surface either shear away or allow the test surface to slip past the helmet.  This is to minimize the amount of twisting force the helmet would transmit to the wearer’s head and neck.  Projections from the helmet (snaps, rivets, etc.) may not exceed 2 mm.

Another test assesses the rigidity of the shell of the helmet by measuring the deformation of the helmet shell when progressively more load is applied up to 630 Newtons (141.6 lb.).

In addition to these areas, ECE 22.05 includes performance for the visor on a helmet, if it is an integral part of the helmet.  DOT provides standards for visors and other eye-protection gear in a separate standard referred to as VESC 8 (Vehicle Equipment Safety Commission).  The ECE standards do not include a test for penetration resistance.

The ECE standard includes requirements for retroreflective materials that may apply in specific member countries.

Unlike the DOT system, where the product is not subject to third-party testing prior to sale, the ECE system required batch sampling when production begins, submission of up to 50 sample helmets/visors to a designated laboratory working for the government that uses the ECE standards under the United Nations agreement and verification of quality control during on-going production.

The ECE standard specifies which type or configuration of helmet the approval applies to, using the following codes: “J” if the helmet does not have a lower face cover, “P” if the helmet has a protective lower face cover, or “NP” if the helmet has a non-protective lower face cover, (stated as ECE 22.05J, ECE 22.05P or ECE 22.05NP).

Snell (Snell Memorial Foundation M2010) Helmet Standard:  

The Snell Memorial Foundation is a private, non-profit organization formed in 1957 dedicated to improving helmet safety.

Snell goes beyond the governmental standard-setting approach and is available to assist manufacturers with helmet development by offering prototype testing.

Once development is completed, manufacturers seeking certification submit sample helmets to Snell for testing using the Foundation’s standardized tests.  If the helmet passes all the tests, it will receive certification under the standard (currently designated M2010) and the manufacturer can label the helmet as Snell certified.

Once a given model design is certified, it cannot be altered in production.  Post-marketing random testing is also conducted by the Foundation to verify continued compliance.  Failure during random testing can lead to de-certification of the helmet.

Snell certification is voluntary and is not required by federal or international authorities, but may be required by some competition sanctioning bodies.

Snell Foundation testing evaluates each helmet model in four areas and specifications for pre-test environmental conditioning of helmets are used.  As with the other two systems, 105° of peripheral vision from the midline is required.

Impact absorption testing is done in similar fashion to ECE and DOT, using a free-fall drop test from a fixed height with a head form in the helmet to measure impact energy transferred to the interior of the helmet when dropped on to a fixed anvil.

Five different anvil shapes are used in the testing.  The peak acceleration energy allowed is 300 G, though the peak acceleration allowed depends on the test and most are somewhat lower.

The height the helmet is dropped from varies; the velocity reached by the impact point is what is specified in the test specifications, ranging from about five to nearly eight meters per second for certification tests.

Protection provided by the helmet shell from penetration is tested by dropping a 3 kg (6.6 lb.) pointed striker on the helmet from a height of 3 m (9.8 ft.).  The helmet fails the test if the striker penetrates the helmet shell making contact with the headform.

Full face helmets are tested for strength of the chin bar by mounting the helmet chin bar facing up in a jig and dropping a 5 kg (11 lb.) weight onto the chin bar midpoint from a fixed height and measuring the amount of deflection the impact causes.  Deflection of 60 mm (2.3 in.) or more or failure of the chin bar likely to result in injury to the wearer means failure of the test.

Positional stability or “roll-off” is tested using a 4 kg (8.8 lb.) weight attached to first rear edge of the helmet by a cord with the helmet positioned and properly strapped on a headform facing downward at a 135° angle such that when the weight is released, it would tend to try to dislodge the helmet from its correct position on the head form.  Then the helmet is rotated 180°, the weight is attached to the front edge of the helmet opening and the test repeated.  Failure occurs if the helmet rolls off the head form.

The retention system is tested by first applying a 23 kg (50.6 lb.) tension load to the fastened chin strap for one minute, then simultaneously removing that load and imparting a 38 kg (83.6 lb.) guided fall load to the closed strap system.  Breakage or deflection of the strap in excess of 30 mm results in failure of the test.

The face shield, if applicable, is tested for penetration resistance by being shot in three spots along the centerline with an air rifle using a pointed lead pellet at a velocity of approximately 500 kph.  Penetration of the shield means failure and for racing helmets, any bump raised by the impact on the inside surface of the shield cannot exceed 2.5 mm in height.

Flame resistance is also tested under Snell standards, but only for specific types of racing helmets.

The Snell label identifies the type of application the helmet is certified for, using letter codes:

  • M=motorcycle
  • SA=special application
  • SAH=special application, frontal head restraint system
  • K=karting
  • CMR=children’s motorsports restricted
  • CMS=children’s motorsports standard



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