Work Zone Mobility and Safety Program
Photo collage: temporary lane closure, road marking installation, cone with mounted warning light, and drum separated work zones.
Office of Operations 21st Century Operations Using 21st Century Technologies

Text from 'Intrusion Devices—New and Emerging Technology in Worker Safety' PowerPoint Presentation

Slide 1

Intrusion Devices - New and Emerging Technology in Worker Safety

Ken Kochevar

FHWA Safety/ITS Specialist

(916) 498-5853

Speaker notes: Good morning! My name is Ken Kochevar. I am the Federal Highway Administration Safety/Intelligent Transportation System Specialist from the California Division office. I will be talking to you today about Intrusion Devices - New and Emerging Technology in Worker Safety.

Two things I look for at a workshop:

  1. Something new.
  2. Something I can use.

Slide 2

Today - Standing in for Ken

Jack Carr, P.E.

Retired from the California Department of Transportation

Office 916-972-7688 Cellular 916-698-0896

Slide 3

If They Only Knew What Was Coming!

Photo: Roadway workers and equipment on a 3-lane highway.

Speaker notes: This is a situation that we encounter too often. I'm not here today to tell you how we can change the attitudes or mindset of these workers, but what instruments we have available to help give us a warning. Intrusion devices do not take the place of a physical barrier, but they will give the worker or inspector a number of seconds to clear the area should a vehicle enter the work zone.

The idea of intrusion alarms is not a new concept.

Mid-80's: Lookout with a loud horn or whistle who watched traffic and could give the alarm while there was escape time.

Over the years many devices have been tried.

Weight, installation demands, access problems and false alarms have not treated them kindly.

Discussed positively in the recent NCHRP 476 report.

Systems approach:

  • Work site layout and planning
  • Barriers and protective vehicles
  • Look-outs and alarms
  • Employee training

Slide 4

U.S. and California Statistics: 1998 - 2001 Work Zones

U.S. Fatalities/Injuries

1998: 772/38,324

1999: 872/50,701





CA Fatalities/Injuries






Speaker notes: All the data you see is from Fatality Analysis Reporting Systems (FARS) and the National Workzone Clearing House.

  • The data covers four years and gives you an indication as to the increase in injuries and fatalities from the years 1998 to 2001.
  • Fatalities rose from 772 in 1998 to 1079 in 2001, an increase of 33%. Injuries also increased at a rate of 25%.
  • California for the same time period shows even worse results. From 1998 to 2001 there was 62 percent increase in fatalities with a high of 121 fatalities in 2000.

These numbers are not rates, but just a way of giving us some idea of which direction we are headed.

Added note - During the middle/late 90's California modified it's accident reporting practices. Prior informal practice was to have the investigating officer determine in the field if the active construction had any impact on the accident. If there was no impact, the Officer may not report the accident as occurring in a construction/maintenance zone. Current practice is to report all accidents in or adjacent to an active work zone as work zone related.

Slide 5

Reasons for Fatality/Injury Increases???

  • Increase of VMT
  • Lack of Consistency
  • Distracted Driver
  • Increase in Nightwork
  • Increase in Funding

Diagram: Chart showing VMT (Vehicle Miles Traveled, in millions) over 4 years. In 1998, there were approximately 2625 million VMT, 1999 had approximately 2690 million VMT, 2000 had approximately 2750 million VMT, and 2001 had approximately 2775 million VMT.

Photo: Humorous electronic highway sign that reads "Some asshole talking on his cell phone got creamed"

Speaker notes: With my 10 years of experience in the work zone area here are some things that I believe have contributed to the increase we see in injuries and fatalities.

There has been a steady increase in Vehicle Miles Traveled (VMT) over the years. In 1998 there were 2,628,198,000 miles traveled verses 2,778,000,000 in 2001. This is about a 2% increase per year.

The next factor deals with consistency. We constantly preach the importance of consistency throughout the work zone as well as from one work zone to the next. We the human mind having to process 200 + decisions in a mile of roadway, inconsistent messages are the last thing we need to worry about.

The 'Distracted Driver' is another increasing alarming factor. People can and do things they shouldn't do in a vehicle. One of the growing concerns I have is the use of cell phones - another full day of discussions.

I believe the increased amount of night time work in and of itself has lead to the increase of injuries and fatalities. In California alone, 60% of major work is done at night time to ease traffic congestion.

Finally, these increases are because of the amount of construction work. In FY02, Caltrans has 619 ongoing contracts - that's one in 5 miles of state highways under construction. There is $20 B programmed for construction in the future with Federal, State and Local funds.

Now, not all injuries and fatalities are workers on foot, but these are the people that have the least chance of surviving if involved in a crash. State & Federal Agencies are actively seeking solutions to this problem and intrusion devices are one such solution.

Slide 6

Perimeter Protection Systems

As an example let's look at

Slide 7

Safety Line SL-D12 Work-Zone Intrusion Alarm

Photo: Two roadway workers watching traffic on a highway.

Speaker notes: The first intrusion device I would like to cover is the Safety Line SL-D12 work-zone intrusion alarm.

This technology grew from the earlier deployment of look-outs.

Slide 8

Safety Line SL-D12 Overview

Diagram: Illustration of the SL-D12 Work Zone Intrusion Alarm system.

Speaker notes: The purpose of the Safety Line™ and other similar systems is to give workers the earliest possible warning that a vehicle has entered a "safety zone" such as a taper, that is closed off by cones, drums, or other channelizing devices (TCD).

Slide 9

Safety Line SL-D12 Operation

Diagram: Illustration of a typical SL-D12 setup that shows a bird's eye view of a work zone. The two-lane road runs from left to right.  The SL-D12 transmitter unit is placed at the bottom left of the lower lane. The SL-D12 receiver and alarm unit is placed on the right side of the lane dividers. Traffic cones run in a rising diagonal lane from left right, between the two SL-D12 units. The top lane is open to traffic.  The work crew is positioned below and to the right of the traffic cones.

Speaker notes: The Safety Line™ consists of a Transmitter and Receiver. The Transmitter is placed at the start of a taper just inside of the channelizing devices. The receiver can be placed up to 1000 feet away, closest to the workers. The transmitter projects a dual Inferred beam to the receiver. Should a vehicle intrude into the buffer area, the dual transmitted beams would be obstructed thus causing the receiver to activate the 147 db air horn, alerting the workers.

Systems offered by other manufacturers may use pneumatic tubes, light beams of various configurations or in some instances a radar beam (micro-wave). The essential element is that a vehicle crosses a line of demarcation.

Some systems, including the "Safety Line" provide for linking together multiple units to protect a larger area.

Slide 10

Safety Line SL-D12 Transmitter and Receiver

Photo: Close-up of the SL-D12 transmitter, with the solar receiver option installed.

Photo: Close-up of the SL-D12 receiver, with the solar receiver and strobe light options installed.

Speaker notes: Here's a close-up of the transmitter and receiver.

The transmitter has the solar charger option and the receiver has the solar charger and strobe light option.

Switches are recessed to prevent accidental activation.

Battery access doors are at the bottom with a detailed set of instructions on the inside.

The alarm is right above the door access in the receiver.

Slide 11

Safety Line SL-D12 Specifications

Cost: $4,000/pair

Range: 1000 Feet

Power Supply: 12 Volt DC

Battery Type: Sealed Gel Cell  (3 day life)

Operating Temperature: -40 degrees to +140 degrees Fahrenheit

Siren Level: 147+ dB Air Horn at 30 feet

Infrared Source: Pulsed infrared beam with background noise suppression

Weight : 21 lbs each

Speaker notes: The cost per pair of the safety line SL-D12 units is $4,000. The range is up to 1000 feet. The power supply is 12 Volt DC. The battery type is sealed gel cell with a 3 day life. There is an option to add solar panels to extend battery life another day or two. Recharging of batteries is between 5 and 6 hours. No battery charger included. Only need a little 12 volt DC charger (minimal cost). The operating temperature range is –40 to +65 degrees C and -40 to +140 degrees F. The siren level is 147+ dB at 30 feet. The infrared source is pulsed infrared beam with background noise suppression. The weight is 21 lbs. each.

Slide 12

Safety Line SL-D12 Benefits

  • Low impact rating of 5 mph.
  • Classified as Category II device under NCHRP350.
  • Quick and easy setup.
  • Length of coverage.

Speaker Notes: The Safety Line Work Zone Intrusion Alarm is molded from UV stable ABS plastic which has an impact rating of 5 MPH. Should a vehicle strike the unit, it will crumble.

Classified as Category II device under NCHRP 350. NCHRP-350 status and impact behavior will not be the same for all systems. Currently, the SL-D12 intrusion device is going through testing with FHWA's Hqs. for NCHRP 350 Category II testing and approval

Setup of the Safety Line can be accomplished in less than 15 minutes by one person. There are no road tubes to roll out and stake to the roadway. 1 minute with 2 people who have used the system.

The Safety Line unit can cover up to 1000 feet and be extended with additional units. This characteristic will vary among manufacturers.

Slide 13

Safety Line SL-D12

ASTI Transportation Systems

Contact us at:


ASTI Transportation System

18 Blevins Dr.

New Castle, DE 19720

Tel: (302) 328-3220

Noah S. Jenkin

Slide 14

Multiple Point Protection Systems

As an example let's look at The SonoBlaster!®

Slide 15

The SonoBlaster!®

'Dual Alert™' Work Zone Intrusion Alarm

Image: An orange traffic cone with a yellow, upside-down T-shaped metal arm (the SonoBlaster) attached to one side.

Speaker notes: The next intrusion device I would like to cover is the SonoBlaster by Paedia.

According to the manufacturer the SonoBlaster!® Dual Alert™ Work Zone Intrusion Alarm is an impact activated safety alarm that warns both roadway workers and errant vehicle drivers at the same time to prevent crashes and injuries in our nation's highway work zones.

The SonoBlaster mounts on standard work zone barricades such as traffic cones, drums, A-frames, delineators and other types of barriers. Upon impact by an errant vehicle, the SonoBlaster's built in CO2 powered horn blasts at over 125 dB to signal.

Slide 16

How the SonoBlaster!® Works

  • SonoBlaster® Alarm Units Mount to Individual Traffic Cones, Drums and Delineators or Barricades
  • Upon Impact, Units 'Sound-Off' at Over 125 dB for approx. 15 Seconds
  • Each Unit Operates Independently
  • Powered by Safe, Reliable CO2 Cartridges

Image: An orange traffic cone with a yellow, upside-down T-shaped metal arm (the SonoBlaster) attached to one side.

Speaker notes: SonoBlaster!® 'Dual Alert™' Work Zone Intrusion Alarm Product Description

The SonoBlaster Intrusion Alarm is a portable, multi-use safety alarm designed to be attached to cones, drums or other barricades to provide protection for personnel in work zones.

It's a lightweight, economical unit that is activated by shock, impact or tilt and is insensitive to road vibration.

When impacted by an errant vehicle, the SonoBlaster provides a very loud 125+ dB alarm sound for 15 seconds.

Powered by safe CO2 cartridges that have an extremely long shelf life, the self-contained unit is easy to operate and does not rely on batteries for operation.

The SonoBlaster has a distinctive sound, not normally heard in a work zone, to attract maximum alarm attention.

Slide 17

The SonoBlaster!®'Dual Alert™'

Notifies Workers:

  • Provides advance warning to workers allowing them the opportunity to move out of harm's way.
  • The alarm sound pinpoints the source of danger.

Notifies Drivers:

  • Each SonoBlaster cone sounds a 125+ dB alarm.
  • Alerts drowsy or distracted drivers.
  • Drivers can respond by braking or steering out of the work zone - or both.
  • Modern cars and SUV's can stop in 120 to 150 feet.

Speaker notes: The SonoBlaster provides a 'Dual Alert™' Approach to Work Zone Protection:

The SonoBlaster Alerts Workers: SonoBlaster cones placed within 100 yards of a work zone can provide workers 3 to 5 seconds warning time to take action. A simple orientation trains workers to respond to the SonoBlaster's distinct warning signal.

The SonoBlaster Alerts Errant Vehicle Drivers. Drivers have tremendous resources at their disposal to correct the path of an errant vehicle: brakes and steering. Upon hearing the SonoBlaster's alarm, the driver can instantly take one or more of the following evasive actions:

Drivers can steer back onto the roadway - Often only a small steering correction will re-direct an errant vehicle out of the 'Cone Zone' and back onto the roadway.

Drivers can apply braking - Modern vehicles with ABS brakes are capable of short stopping distances while continuing to steer away from danger.  Even heavy SUV's are capable of very short stopping distances. Typical 60 mph vehicle stopping distances range from 120 to 150 feet. (40-50 yds.)

Simultaneously alerting both drivers & workers greatly increases the probability of preventing injuries.

Slide 18

The SonoBlaster!

A New Concept in Work Zone Intrusion Alarms

  • Uses No Electrical Power
  • Alerts BOTH Workers and Drivers
  • Pinpoints the Source of Oncoming Danger
  • Provides Multiple Warnings
  • As Easy to Deploy as Setting a Traffic Cone

Speaker notes: Paedia's unique SonoBlaster!® Work Zone Intrusion Alarm claims to have established several new 'Firsts' in Work Zone Safety Alarms.

The SonoBlaster:

  • Requires No Electrical Power - Powered by safe, reliable CO2 cartridges, the SonoBlaster has an 'infinite' shelf life & won't 'go-dead' or loose power while waiting to do its job.
  • Notifies Both Workers and Drivers - The ability of the SonoBlaster to alert both errant vehicle drivers and highway workers at the same time creates a new level of protection for preventing crashes and injuries in a wide variety of work zones
  • Identifies the Source of Danger - The source of the alarm sound is always the source of danger. Intrusion alarms that place audible receiver alarms in the work zone, which may be behind some workers, can direct worker's attention the wrong direction. With the SonoBlaster, the source of the alarm sound, which moves as an errant vehicle hits successive cones, moves along with the danger. The source of the SonoBlaster alarm sound pinpoints the source of danger allowing proper response by workers who find themselves in harms way.
  • Provides Multiple Warnings - Each SonoBlaster cone struck by an errant vehicle sounds an independent 125+ dB alarm providing a continuous warning for both workers and drivers.

Added comment - Can this alarm cause a driver to respond in an erratic or unpredictable manner? A point to be considered in reaching a decision. Mentioned a much earlier systems that used strobe lights to "wake-up" the driver which was rejected because of the perceived threat of an unpredictable reaction.

Slide 19

Preparing & Cocking the Unit

Simple Unit Setup Steps:

  1. Push the cocking rod into the end of unit, cocking the unit.
  2. Twist-on a 16-gram SonoBlaster CO2 cartridge in the cartridge holder.

Visual Status Indication:

  • View the status indicator through the clear indicator window showing that the unit is properly cocked.

Photo: Close-up of someone cocking the unit.

Photo: Close-up of the visual status indicator.

Speaker notes: The SonoBlaster Unit is Simple to Setup:

The SonoBlaster is cocked using a small 4" long cocking rod. It is small enough to fit in a pocket and has a lanyard and ring to prevent loss or it can be attached to the SonoBlaster.

  1. Pushing the small rod into end of SonoBlaster cocks the unit.
  2. Twisting on the CO2 cartridge in its cartridge holder completes the job.

Confirmation that the unit is cocked and ready to deploy is done through the Status Indicator Window.

Visual Status Indication

  1. View the status indicator through the clear window. If the red horizontal mark lines up with the window, the unit is properly cocked and ready to go to work. If not, the red mark will not be visible and the cocking procedure should be repeated.

Slide 20

SonoBlaster!® Work Zone Arming and Deployment

  • SonoBlaster® units can be deployed and retrieved from a cone truck the same as standard traffic cones.
  • The position of the unit's activating arm near the top of the cone allows a "cone setter" to easily disarm a unit prior to lifting it off the roadway.

Speaker Notes: Caltrans provided SonoBlaster with the use of a cone truck to design the ergonomics of the SonoBlaster's activating arm for deployment of SonoBlaster units from the seat of the cone truck.

  • SonoBlaster units can be deployed and retrieved from a cone truck the same as standard traffic cones.
  • The position of the unit's activating arm near the top of the cone allows a "cone setter" to easily:
    • Set the cone on the roadway and arm the unit, and,
    • Disarm the unit prior to lifting it off the roadway.

Slide 21

SonoBlaster!® Activation

  • Shock Activation - The unit fires upon direct vehicle impact.
  • Tilt Activation - The unit fires when tilted from its normal upright position.
  • Stability - The SonoBlaster® is resistant to normal roadway harmonics and vibration.

Photo: The front bumper of car knocking over a SonoBlaster cone.

Speaker notes:

  • The SonoBlaster unit fires upon direct vehicle impact.
  • The unit also fires when tilted 90 degrees from vertical.
  • The SonoBlaster is resistant to normal roadway harmonics and vibration.

Stability and False Alarm resistance are critical strengths of the SonoBlaster.

Slide 22

Typical SonoBlaster!® Layout

Diagram: Illustration showing a typical SonoBlaster layout. The two-lane road is oriented horizontally. Traffic flow is from right to left.  Starting on the right edge of the road, 26 traffic cones are placed down the middle of the two lanes running for 300 feet. The first 4 cones on the far right are standard traffic cones. The next 15 are SonoBlaster cones. The last 7 are standard traffic cones. The work zone begins at the 15th SonoBlaster cone and extends to the last traffic cone on the left edge of this section of road. Two additional SonoBlaster cones are placed perpendicular to the first SonoBlaster cone on the right hand side, extending toward the top edge of the road.

  • A Typical 100 Yard SonoBlaster® Protection Zone.
  • Cone Spacing = Approximately 20 Feet Apart.
  • Requires only 17 SonoBlaster Equipped Cones.
  • Can provide up to 5 seconds or more advance warning - depending on vehicle speeds in the Work Zone. Additional time is afforded if errant vehicle driver begins braking.

Speaker notes: This slide shows one of many potential SonoBlaster Work Zone Protection layouts. (Note: Chart is NOT to Scale)

  • Just 17 cones can provide a 300 foot protection zone in advance of a work zone.
  • This type of protection layout can provide up to 5 seconds or more of advance warning time for workers.
  • Additional time is afforded if a driver applies braking upon hearing the warning alarm.

Slide 23

Work Zone Friendly

Diagram: Illustration showing that the SonoBlaster!® cones are work zone friendly. As vehicles enter a work zone, they can move in between the cones without tripping off a false alarm.

  • Vehicles & workers can pass between SonoBlaster Cones at slow speed without causing false alarms

Speaker Notes: Work Zone Friendly - According to the manufacturer -

  • Workers & vehicles can move freely around SonoBlaster!® equipped cones & barrels without fear of inadvertently tripping-off a false alarm.
  • Vehicles can enter and leave the work zone without the nuisance of deactivating the worker's zone of protection.
  • Beam Type intrusion alarms rely on an invisible beam whose location is not always apparent to workers. Accidentally interrupting the beam during normal work operations causes unwanted false alarms diminishing the effect of an intrusion alarm system. In addition, paper or other debris can blow through the beam and create false alarms.
  • The layout pattern of a SonoBlaster protection zone does not need to be a straight line and can be curved, shaped or designed to accommodate the job at hand.
  • Added comment - The manufacturer's suggested 20 ft. spacing could cause entering vehicles to slow excessively while in the live traffic lane. That this could be unacceptable on a high speed facility.

Slide 24

The SonoBlaster!® Work Zone Intrusion Alarm

NCHRP 350 Category II Accepted for use on:

  • Drums
  • Traffic Cones
  • Large Base Delineators

Photos: A traffic cone, drum and large base delineator

Speaker Notes: SonoBlaster has conducted both low and high speed crash trials with great results.
In all trials, SonoBlaster equipped cones passed under test vehicles with no windshield contact.
NCHRP 350 accepted for attachment to:

  • traffic cones
  • drums, and
  • large base delineators

See our website:

  • Video Movie of 60 MPH SonoBlaster Crash Test
  • Conducted by Caltrans at California Highway Patrol Academy / Proving Grounds in W. Sacramento, California.
  • Crash Test filmed by FHWA.

Slide 25

SonoBlaster!® Applications

SonoBlasters work with:

  • Traffic Cones
  • Drums
  • Large Base Delineators
  • A-Frames
  • Type III Barricades
  • Security Fences
  • Manhole Guards
  • More . . .

Photo: An orange traffic drum with a SonoBlaster attached to one side.

Photo: A narrow, orange traffic cone with a SonoBlaster attached to one side.

Speaker notes: SonoBlaster units work in conjunction with standard cones, barricades, drums, A-frames, large base delineators, safety fences and manhole guards.

Additional stands or receiving equipment setups are not required.

The SonoBlaster mounts on:

  • Traffic Cones 28" or taller
  • Drums with open bottom access
  • Portable Delineators with minimum lower tube diameter of 5"
  • A-Frames
  • Type III Barricades
  • Security Fences
  • Manhole Guards
  • and more . . .

The SonoBlaster is semi-permanently mounted via simple bolts, nuts and washers.

Installation takes just a few  minutes and requires just a 1/4" drill, wrench and screwdriver.

Slide 26

SonoBlaster!® Uses

  • Construction Sites
  • Flagger Protection
  • Stripping & Marking Operations
  • Bridge Inspection & Repair
  • Paving & Grading Operations
  • Joint & Crack Sealing
  • Survey Crew Protection
  • Patching & Pot Hole Repairs
  • Signal & Sign Maintenance
  • Equipment Unloading
  • Intra-Work Zone Protection
  • Grade Crossing Repairs
  • Aerial Platform Work
  • Pedestrian / Bike Protection

Speaker notes:

See above multiple product uses and applications.

Additional Uses:

  • Sweeping & Street Cleaning
  • Snow and Deicing Operations
  • Equipment Break-Downs
  • Site Inspection Crews
  • Mowing & Landscaping
  • Tree Trimming
  • Disaster / Hazmat Scenes
  • Police & Fire Operations
  • Crash Scenes
  • More . . .

Slide 27

SonoBlaster!® FHWA Accepted NCHRP 350 Approved Category II Safety Device

Findings from FHWA letter dated September 16, 2002: The results of the testing met the FHWA requirements and, therefore, the SonoBlaster described above and shown in the enclosed drawings for reference are acceptable for use on the NHS under the range of conditions tested, when proposed by a State.

We consider the SonoBlaster to be acceptable when attached to the base of conventional traffic cones, plastic drums, or large base road tubes or delineators (i.e., the "Navigator®" manufactured by Plastic Safety Systems).

Speaker Notes:

  • NCHRP350 testing is complete and has been approved by FHWA HQs (Nick Artimovich) as an NCHRP 350 Category II Safety Device. A copy of the acceptance letter is available on the FHWA website (September 2002).
  • In all trials, SonoBlaster equipped cones passed under test vehicles with no windshield contact.

Slide 28

Clipping from magazine: December 2002 issue of Better Roads Magazine, "Top 50 New Products of 2002." The SonoBlaster is recognized in the article.

The clipping reads "Work-zone traffic cones sound off for safety. The new SonoBlaster attaches to a standard traffic cone and emits a shrill, 125-decible blast warning workers and the driver alike that an errant vehcile has entered the work zone. The devices are powered by carbon dioxide cartiridges, which the company says won't go dead like batteries. Patented SonoBlaster cones disarm when nested together."

Speaker Notes: Paedia has received a trial order from the New York State DOT and was named one of Better Roads Magazine's Top 50 New Products of 2002 in the December issue.

Slide 29


Technical Specifications

Sound Level: 125+ dB @ 6 feet (peak), 80+ dB @ 300 feet

Alarm Duration: 15 Seconds (approximate)

Size: 10" wide by 20" tall

Unit Weight: 4 lbs.

Angle of Activation: 70 to 90 degrees from vertical

Operating Temperature Range: 0 to +110 degrees Fahrenheit

CO2 Cartridge Size: 16 Grams

Cartridge Temperature Range: -30 to +120 degrees Fahrenheit

Cartridge Shelf Life: Indefinite

Specifications Subject to Change Without Notice

Speaker notes: The volume user cost is currently $149.85 making the cost of a 300 foot, 17 unit SonoBlaster Protection Zone less than $2,550.00.

Each SonoBlaster unit and includes:

  • The SonoBlaster unit & Cartridge Holder
  • Cocking Rod and Lanyard
  • Mounting Hardware & Mounting Instructions
  • Operating Manual

CO2 Cartridges cost around $0.69 each.

Cones, Drums, etc. are not included

A Training Video is available.

Slide 30


International Road Dynamics

Contact us at:


International Road Dynamics

702 43rd Street East

Saskatoon, SK S7K 3T9

Tel: (306) 653-6600

Rod Klashinsky

Slide 31

Zone Protection Systems

As an example let's look at Wireless Warning Shield

Slide 32

Wireless Warning Shield

Innovations From Logic Systems, Inc.

Speaker notes: The last intrusion device I would like to cover is the 'Wireless Warning Shield' from Logic Systems, Inc.

Creates a protected zone without the use of tubes or beams, therefore making ingress and egress less of a problem. More flexible than perimeter protection system.

This product is just now coming to market and shows the potential that can be realized with "smart" products. Formal introduction of this product to the market will probably occur this fall.

Slide 33

Wireless Warning Shield

How It Works!

  • Vehicle strikes a TCD equipped with the PRT-300.
  • A "Radio Chain Reaction" occurs.
  • All receivers within range of any PRT-300 will sound off.
  • Workers react to the danger coming their way.

Speaker notes: This uses a coded repeater style radio system. The unit that is triggered via the internal shock sensor, transmits a radio signal. This signal is picked up and retransmitted by the next 2 or 3 PRT-300 repeaters and each of them repeat as well, and so on. Since our range is up to 300 feet, several cones should be triggered at once causing redundancy of repeater points. This increases reliability of the repeater chain.

The signal is also picked up by any of the receiving alarm systems that are within range. These alarms, whether Area Alarms, Personal Body Alarms, or Headphone alarms, will all signal a "hit" indicating possible danger.

Slide 34

Wireless Warning Shield

The Building Blocks

  • PRT-300 repeating transceiver.
  • Several styles of receivers and warning devices.

Speaker notes:  The WWS is made up several building blocks integrated into a two part system. These two parts consist of the PRT-300 repeating transceiver and several styles of receivers and warning devices.

Slide 35

Wireless Warning Shield

Data Processor

The processor will take data from the shock sensor and determine if it was a strike or just vibration. It will ignore vibrations, and signal if struck. The PRT-300 will also ignore wind caused tip overs! If data is from the receiver, it will verify a valid code exists, then signal.

Graphic: Processor and Transmitter communicate data through the code.

Speaker Notes:

**Add to previous section during discussion.

  • Six different coded units: Red, Blue, White, Black, Green, and Yellow.
  • Each Code can be used as a direction or segmentation of a larger work area.

PRT-300 has both:

  • shock sensor
  • radio receiver

Slide 36

Wireless Warning Shield

Receivers and Warning Devices

Image: Illustration of an area alarm, 4 personal body alarms, a personal headphone alarms, and a personal hardhat alarm.

Speaker notes:

  • AR-100 Area Alarm: Recommended for each site as an overall alarm broadcaster. It also houses the low batter enunciator.
  • PBA-100 Personal Body Alarms: Recommended for each construction site personal. Especially if they move around the Zone away from the AR-100.
  • PHA Personal Headphone alarms: Recommended for persons using high noise level equipment such as jack hammers.
  • PHH Personal Hardhat Alarm: Recommended for all work personnel.

* Currently focusing on the Area Alarm and Personal Body Alarms.

Slide 37

Wireless Warning Shield

AR-100 *Area Alarm

The AR-100 is designed for an area alarm system. It has a very high decibel output level when triggered.

Image: Illustration of an AR-100 area alarm

Speaker notes: The AR-100 is intended to be an overall localized group alarm. Unlimited number of AR-100's may be used in any Zone.

The AR-100 also contains the following features:

  1. Each sounder emits an over 125db signal and is easily distinguishable from traffic noises.
  2. Zone selectable.
  3. Receives low battery signals from PRT-300s triggering a battery warning and
  4. Contacts for customer connected signaling device such as a cell phone or flashing lights.
  5. Compact and tripod mountable, weather resistant design. The unit may stay outside rain or shine.
  6. Approx. cost = $200.

Slide 38

Wireless Warning Shield

PBA-100 Personal Body Alarm

  • The PBA-100 is Zone selectable
  • Extremely loud alarm and strong vibrator
  • Resembles a pager
  • For individual use

Image: Illustration of a PBA-100 Personal Body Alarm.

Speaker notes: The PBA-100 is for everyone on the work site, especially for someone that is not within earshot of the AR-100 Area alarm. They stay on the person of the user. They can be triggered via any of the PTR-300's in the programmed Zone that are within range.

  1. They are self contained units much like a pager in size. They contain a powerful vibrator and a very loud audio alarm (100+ dB).
  2. Will not trigger from low battery alarm transmission.
  3. Zone selectable by the user. Will operate in any one of the 6 Zones.
  4. Unlimited number of PBA-100's may be used in any Zone.
  5. Approx. cost = $100.

Slide 39

Wireless Warning Shield

PHA Personal Headphone Alarm

The PHA is designed to be used by persons that would not be able to hear or feel a Personal Body Alarm.

Image: Illustration of a PHA Personal Headphone Alarm

Speaker notes: The PHA can include users of jackhammers or other loud or vibrating equipment. Combines the quieting of safety headphones and the warning ability of the WWS.

Approx. cost = $100.

Personal Hardhat Alarm still in design. Some problems with CalOSHA because of ANTSI requirements.

Slide 40

Wireless Warning Shield


  • Will not trigger on wind only tip over.
  • Does not have the distance and direction limitations of sound only systems.
  • Unlimited number of receivers can be used.
  • Processor functions allow for fewer false triggers from heavy vibrations.
  • Can mount on almost any type of traffic control device.

Speaker Notes:

Advantages of the Wireless Warning Shield:

  1. Unlike strictly audio systems, the direction of sound is not relevant nor is distance limited by the direction of the wind.
  2. The WWS can be extended for an almost unlimited distance if deployed correctly.
  3. Radio driven system with virtually unlimited number of receivers.
  4. Alarms can be for areas and/or individual personal.

Slide 41

Wireless Warning Shield

PRT-300 Specifications

  • Coding Format for Alarms: Channel encoding
  • Transmission Frequency: 915 MHZ
  • Transmission Range: Up to 300'
  • Power Supply: Single C battery, photocell assist
  • Battery Life: Approx. 4-6 months (calculated)
  • Operational Temperature Range: 32 to 158 degrees Fahrenheit
  • Unit Cost: Price $75.00 each (target)
  • Dimensions: 2 x 5 x 1.25 in.
  • Weight: 5 oz.

Speaker Notes:

  • Weight is unknown at this time but expected to be about 4-8 oz.
  • Six different coded units: Red, Blue, White, Black, Green, and Yellow. Each Code can be used as a direction or segmentation of a larger work area.
  • 2" wide by 5" tall by 1.25" thick.
  • Except for the battery compartment, the unit will be encapsulated to withstand weather and for ruggedness.

Slide 42

Wireless Warning Shield

Current Status

  • The WWS is currently in the last stages of development.
  • Physical testing of the concepts and sensors have been successful.
  • Packaging is in development and should be complete within 2-3 months.
  • Field testing to begin shortly after. (Dec. 1)
  • Classified as Category II device under NCHRP 350.

Speaker notes: The Manufacturers are offering to deploy a limited number of systems this construction season for the purpose of Beta Testing. If your agency or company would be interested please see me after the session and I can give you a copy of the manufacturer's letter.

ConQuip, Inc. is currently working with FHWA Hqs. in review and approval of NCHRP 350 testing of the Category II device.

Slide 43

Wireless Warning Shield

ConQuip, Inc.

Contact us at:


Conquip, Inc.

8360 Rovana Circle

Sacramento, CA 95828

Tel: (916) 386-8500

Adam Zielenski

Slide 44

For Any System You Should Consider the following:

  • Safety - What and how are humans exposed to traffic during deployment and retrieval?
  • Safety - Will this cause motorists to react in an unpredictable manner?
  • Ingress and Egress - Can authorized traffic enter and exit without creating a false alarm?
  • False Alarms - How well does the system guard against false alarms?

Speaker Notes:


  • Will workers be exposed on foot during installation and retrieval?
  • Will workers be required to kneel, stoop or face away from traffic?
  • Will this system startle passing motorists? The violating motorists?

Ingress and Egress

  • Will workers have to slow down excessively in traffic when entering the work area?
  • Will slow moving vehicles be forced to enter high speed traffic lanes?
  • Can approach gates be developed that offer reasonable paths to enter and leave?

False Alarms

  • Will traffic control devises blown over case false alarms? How many?
  • Can airborne debris cause false alarms?
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