5.2 Drums & Barricades
Key Takeaways
- Plastic traffic drums must be at least 36 inches in height and 18 inches in width, displaying four horizontal retroreflective stripes (two orange, two white) alternating from orange at the top.
- Type 1 barricades feature a single horizontal rail (8 to 12 inches wide), Type 2 feature two rails, and Type 3 feature three rails spanning a minimum rail length of 48 inches, with at least 270 square inches of retroreflective area facing road users on high-speed facilities.
- Barricade orange and white stripes must measure 6 inches wide and slope downward at a 45-degree angle toward the side where traffic passes.
- Ballast for drums and barricades must be placed at ground level on the base flange or lower structural legs; placing sandbags, concrete blocks, or heavy weights on top of devices creates dangerous flying projectiles during collisions and violates MUTCD/MASH compliance.
- Type 3 barricades should be used to close or partially close a road, and may be placed completely across a roadway or from curb to curb.
5.2 Drums & Barricades
Drums and barricades represent heavy-duty channelizing devices designed to provide high-visibility guidance, define work zone boundaries, and physically discourage vehicle intrusions. Because of their prominent target area and broad retroreflective surface, traffic drums and Type 1, 2, and 3 barricades are essential tools for high-speed expressways, long-duration construction projects, and major road closures. IMSA Work Zone Technicians must master MUTCD design standards, crashworthiness criteria, retroreflective striping angles, and ballasting rules to deploy these devices safely.
Traffic Drums (Barrels): Specifications & Design
Traffic drums are hollow, polyethylene or plastic cylindrical devices recognized for their exceptional target size and 360-degree visibility.
MUTCD Dimension Standards
To comply with MUTCD Part 6 standards, traffic drums must meet the following physical specifications:
- Minimum Height: Must be at least 36 inches (900 mm) from the road surface to the top of the drum body.
- Minimum Width: Must present a minimum width/diameter of 18 inches (450 mm) facing approaching traffic from any directional angle.
- Body Construction: Constructed of flexible, high-density polyethylene (HDPE) or similar impact-resistant plastic that deforms upon vehicular impact without causing dangerous decelerations to the impacting vehicle.
Horizontal Retroreflective Striping Pattern
Traffic drums must be wrapped with alternating orange and white retroreflective sheeting. The MUTCD mandates a minimum of four horizontal retroreflective stripes:
- Stripe Width: Each horizontal stripe must be 4 to 6 inches wide.
- Stripe Order: The top band must be orange, followed by alternating white, orange, and white bands.
- Stripe detail: Non-retroreflectorized spaces between the orange and white stripes shall not exceed 3 inches in width, and drums shall have closed tops that will not allow debris to collect. Metal drums shall not be used. The MUTCD specifies no sheeting grade for drums.
+-----------------------+
| ORANGE BAND (6") | <-- Must start with Orange at top
+-----------------------+
| WHITE BAND (6") |
+-----------------------+
| ORANGE BAND (6") |
+-----------------------+
| WHITE BAND (6") |
+-----------------------+
| BASE / BALLAST | <-- Sandbags or tire collar at base ONLY
+-----------------------+
Critical Ballasting Safety Rules for Drums & Barricades
Improper ballasting of traffic control devices is one of the leading causes of preventable fatalities in work zone accidents. Ballast must hold devices steady against high winds and vehicle wake turbulence without compromising crashworthiness.
The Ground-Level Ballast Rule
Under MUTCD Section 6K.06 (drums) and Section 6K.07 (barricades), and under AASHTO MASH crash-test criteria — which superseded NCHRP Report 350 for temporary work zone devices manufactured after December 31, 2019:
- Ballast Position: All ballast must be placed at ground level on the base flange of the drum or on the lower cross-members/legs of barricades.
- Approved Ballast Types: Acceptable ballast includes recycled rubber base collars (tire rings weighing 25 to 50 lbs) designed specifically for the drum base, or sandbags placed flat on the ground flange.
- Maximum Weight: Drums should not be weighted with sand, water, or any material to an extent that would make them hazardous to road users or workers when struck; the MUTCD states no pound figure and the permissible ballast is set by the manufacturer's crash-test certification.
Strict Prohibition of Top Ballasting
CRITICAL SAFETY MANDATE: Under no circumstances should sandbags, concrete blocks, asphalt chunks, rocks, or heavy objects be placed on TOP of traffic drums or on upper barricade rails.
When a vehicle strikes a top-ballasted drum at highway speeds, the drum body collapses downward, launching heavy sandbags or stones directly through the windshield of the impacting vehicle. This creates high-velocity flying projectiles that cause severe trauma or fatalities to vehicle occupants and nearby highway workers.
| Ballast Practice | Safety Status | Crashworthiness Compliance |
|---|---|---|
| Recycled rubber ring placed around drum base collar | APPROVED | MASH Compliant |
| Sandbags placed flat on base flange at ground level | APPROVED | MASH Compliant |
| Sandbag resting on top lid of traffic drum | PROHIBITED | Lethal projectile hazard — VIOLATION |
| Concrete block placed inside upper body of drum | PROHIBITED | Lethal projectile hazard — VIOLATION |
Barricade Classifications: Type 1, Type 2, & Type 3
Barricades are portable or fixed frames with horizontal rails displaying orange and white retroreflective stripes. The MUTCD categorizes barricades into three distinct structural types based on rail count, rail dimensions, and operational use.
Type 1 Barricades
- Rail Configuration: Features one horizontal rail.
- Rail Dimensions: Rail height must be 8 to 12 inches; minimum rail length is 24 inches.
- Primary Applications: Designed for low-speed urban streets, local roads, utility work, and pedestrian channelization where space is limited. The MUTCD states only that Type 1 barricades may be used on conventional roads or urban streets, with no mph threshold.
Type 2 Barricades
- Rail Configuration: Features two horizontal rails.
- Rail Dimensions: Each rail height must be 8 to 12 inches; minimum rail length is 24 inches.
- Primary Applications: Commonly used on conventional rural highways, urban arterials, and expressway lane tapers. Type 2 barricades offer double the retroreflective surface area of Type 1 barricades, improving visual conspicuity on higher-speed facilities.
Type 3 Barricades
- Rail Configuration: Features three horizontal rails.
- Rail Dimensions: Each rail height must be 8 to 12 inches; the minimum rail length shall be 48 inches. Barricades used on freeways, expressways, and other high-speed roadways shall have a minimum of 270 square inches of retroreflective area facing road users.
- Primary Applications: MUTCD Guidance is that Type 3 barricades should be used to close or partially close a road. As an Option they may be placed completely across a roadway or from curb to curb; where access must still be allowed for local road users they usually are not extended completely across the roadway.
| Barricade Type | Number of Rails | Rail Height | Min Rail Length | Typical Work Zone Application |
|---|---|---|---|---|
| Type 1 | 1 Rail | 8" to 12" | 24 Inches | Low-speed urban streets, utility work |
| Type 2 | 2 Rails | 8" to 12" | 24 Inches | Highway tapers, urban arterials |
| Type 3 | 3 Rails | 8" to 12" | 48" min rail (270 sq in retroreflective area on high-speed roads) | Road closures, ramp closures, road breaks |
Striping Angles, Directionality, & Closure Protocols
Barricade rails have alternating orange and white retroreflective stripes sloping downward at 45 degrees in the direction road users are to pass. Stripes shall be 6 inches wide; when rail lengths are less than 36 inches, 4-inch wide stripes may be used. The direction of the diagonal stripes conveys mandatory direction of travel instructions to motorists.
Directional Guidance (Pass Left vs. Pass Right)
- Stripes Sloping Down to the Right: Directs drivers that traffic must pass to the right of the barricade.
- Stripes Sloping Down to the Left: Directs drivers that traffic must pass to the left of the barricade.
- Chevron / V-Pattern (Center Sloping): Used when traffic is permitted to pass on both sides of an island, barrier nose, or median obstruction.
Complete Road Closure Striping Rules
Where barricades extend entirely across a roadway, the stripes should slope downward in the direction toward which road users must turn. Where both right and left turns are provided, the stripes should slope downward in both directions from the center. Where no turns are intended, the stripes should slope downward toward the center of the barricade or barricades.
Warning Lights Mounted on Barricades and Drums
To enhance nighttime visibility, warning lights may be mounted on barricades and drums:
- Type A Low-Intensity Flashing Lights: Warn road users during nighttime hours that they are approaching or proceeding in a potentially hazardous area, and may be mounted on channelizing devices used alone or in a cluster. Flashing warning lights shall not be used for delineation on a series of channelizing devices; the exception is sequential flashing warning lights on a merging taper, which flash from the upstream to the downstream end at 55 to 75 times per minute.
- Type B High-Intensity Flashing Lights: Mounted on advance warning signs to operate 24/7 in high-speed hazardous locations.
- Type C Steady-Burn Lights: Mounted along tangent channelizing runs and barricades to delineate the continuous edge of the travel path through curves and shifts without blinding drivers with flashing glare.
- Type D 360-Degree Steady-Burn Lights: May be used during nighttime hours to delineate the edge of the traveled way; when used to delineate a curve, they should be placed only on devices on the outside of the curve.
Why does the MUTCD strictly prohibit placing sandbags, concrete blocks, or other heavy weights on the top of traffic drums or barricade rails?
Which type of barricade features three horizontal retroreflective rails spanning at least 48 inches and is required for complete road or ramp closures?
What is the correct orientation for the 6-inch orange and white stripes on a channelizing vertical panel or barricade rail directing traffic to pass on the right?