ROAD SURFACE DRESSING ASSOCIATION

 

 

 

 

OPERATOR’S GUIDE TO THE SAFE USE OF

SURFACE DRESSING SPRAYERS

 

 

 

 

 

                           Consultant Director and Secretary

 

                                      John Baxter

                                      Westwood Park

London Road

Little Horkesley

                                      Colchester

                                       Essex CO6 4BS

                                     

 

 


Σ Copyright RSDA 1998

     First Published

     Revised 2004

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
No part of this document may be

reproduced without the written permission

of the Road Surface Dressing Association

 
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


R S D A Guidance Note for Spray Tanker Operators  2004

 

 

 

 

 

FOREWORD

 

 

Safety and quality are two of the major objectives of the Association and this recently revised Guidance Note is designed to help achieve these goals however it is no substitute for a thorough risk assessment which will be specific to site and operational circumstances.

 

The Guidance Note is intended to cover on site operations and is not intended to cover annual maintenance or workshop overhaul.

 

This booklet represents a code of practice which, when followed, will help eliminate accidents and provide for the efficient operation of bulk sprayers and a consistent high quality spray pattern.

 

 As the sprayer is the key item of surface dressing plant, it is vital that operators are fully trained, and that they follow this code and the instructions issued by individual sprayer manufacturers.

 

The Association wishes to promote excellent workmanship, carried out competently and safely for all those engaged in, on and around the surface dressing site.

 

 

THINK QUALITY - THINK SAFETY

Chairman

 

ROAD SURFACE DRESSING ASSOCIATION

 

 

 

SECTION A - OPERATORS' GUIDE TO SURFACE DRESSING SPRAYERS

                                                                                                                                                                        Page

1. Introduction                                                                       4

2. Tanker Labelling                                                                  4

3. Testing and Calibration                                                        4

4. Temperature                                                                      6

5. Pressure                                                                            7

6. Road Speed                                                                       7

7. Transverse Distribution                                                        7

8. Spray Bar Height                                                                 7

9. Baffles and Spray Curtains for Swirling Jets                              8

10. Cleaning of Pumps and Spray Bars                                        8

11. Filters                                                                             8

12. Jets and Blockages                                                            8

13. Heating Binders                                                                 8

14. Safety                                                                            9

15. Spray Bar Operating Linkage                                                9

16. Pressure Control                                                                9

17. Variation in Working Pressure                                               9

18. Speedometer and Fifth Wheel                                            10

19. Air Vent                                                                         10

20. Jet Test                                                                        10

21. Pressure and Temperature                                                11

22. Joints                                                                           11

23. Scavenging the Spraying System                                       11

24. Cleanliness                                                                     11

25. Changing Binders                                                             12

26. Binder Additives                                                              12

 

 

 

 

SECTION B - OPERATORS' SAFETY GUIDE

Page

 

1. Introduction                                                                   13

2. Bulk Sprayers                                                                 13

3. Hazard Warning Panels                                                     14

4. In the Event of Fire                                                         16

5. Burst Pipes                                                                    16

6. Delivery of Materials                                                        16

7. Changing from one Binder to Another                                  16

8. Protective Clothing                                                          17

9. Personal Hygiene                                                            17

10. First Aid                                                                      18

11. First Aid Box                                                                 18

12. Accident Reporting                                                        18

 

SECTION A - OPERATORS' GUIDE TO SURFACE DRESSING SPRAYERS

 

 

1.      INTRODUCTION

 

Good surface dressing depends to a very great extent on applying the binder evenly at the proper rate. Variations in thickness of the binder film can happen in two ways:

 

(a) Incorrect distribution across the road caused by:

(i)       Change in spray temperature and/or pressure.

(ii)      Faults in the spray bar and/or hood.

(iii)     Spray bar height.

(iv)             Poor jointing

 

(b) Variations in distribution along the road caused by:

(i)       Change in pressure and/or temperature.

(ii)      Varying road speed.

 

Good surface dressing therefore depends on keeping a spray bar in good working order and keeping variations in pressure, temperature and road speed under control.

 

2.      TANKER LABELLING

 

Tankers must comply with current regulations for the transportation of dangerous substances and carry the current HAZARD warning panels and TREM card (transport emergency card) for the binder being carried. In other cases it is recommended that the CIA voluntary code for tanker labeling is followed for low hazard products.

 

3.      TESTING AND CALIBRATION

 

The machines should comply with the requirements of BS 1707 "Hot Binder Distributors for Road Surface Dressing" and be tested and certified at least annually by a UKAS accredited agency.

 

If a tanker is to carry a "dangerous substance" under the Carriage of Dangerous Goods Regulations it must also be tested and certified for this purpose under the regulations.

 

The output from the spray bar is measured in litres per minute at spraying temperature and a driver's chart, is made out accordingly. A typical driver's chart for Kl- 70 emulsion is shown below and is an example, but it is important to remember that a SEPARATE CHART should be available for each type of binder used.

 

 

 

DRIVER'S CHART                                        ROAD SPEED/RATE OF SPREAD

 

 

COMPANY……A. N. OTHER…………………………………………………..…..

 

VEHICLE No. …N102CKE……………………..  FLEET No……SD10………….

 

SPRAYBAR ……A SUPPLIER……………………….……………………………..

Conditions of Test

Rate of Spread Litres/m2

Road Speed

MPH

Binder……………………..

K1-702

EMULSION

2.2

1.56

2.1

1.76

Viscosity……………….…

30 SECS

-85°C

2.0

1.95

1.9

2.15

Spray Temperature……..

80 - 85°C

1.8

2.34

1.7

2.53

Spray Height…………….

450 MM

1.6

2.73

1.5

2.92

Pressure………………….

24 PSI

1.4

3.32

1.3

3.51

Litres/min …OVER TOTAL WIDTH

368.8

1.1

3.70

1.0

3.90

Spray Width VARIABLE TESTED AT

3658mm

1.0

3.90

 

 

 

Left Hand Side

Right Hand Side

Butt Joints

OK

OK

Lap Joints

OK

NOT SUITABLE

Overlap for full spray: 75mm                                       For Part Spray: 300mm

 

 

Date:               3.2.97                                        Signed: Joe Bloggs  

 

 

 

4.      TEMPERATURE

 

The binder is heated to the temperatures listed in Table 1, which enables it to be sprayed through the jets.

 

1.                        Swirling Jets

Temperature affects the performance of swirling spray jets in two ways:

 

(a)      The spray from each jet will not swirl properly if the binder is either too hot or too cold.

(b)      The rate of discharge decreases as the temperature rises and increases as the temperature falls. The variation is about 2½% per 5°C (about 5litres per minute for a  standard 2.3 m spray bar.

 

2.                        Slot Jets

When using slot jets, the effect of temperature change is the reverse of those given in 1 (b) above, i.e. the rate of discharge increases with higher temperature.

 

Note:

Solvent-based cut backs are handled at temperatures above their flash point and give off fumes which are a FIRE HAZARD. There is also a risk of explosion. Overheating of any binder is very dangerous (see Health and Safety section of this guide).

 

Table 1

Recommended Spraying Temperatures for Binders

*(Swirling Jet Pattern Spray bars)

Cut-back bitumen

Bitumen emulsions

Viscosity Grade

(BS 3690 Table 2)

 

Spraying

Temp

°C

 

Class

(BS434

Part 1)

 

Spraying

Temp

°C

 

50 secs

 

100 secs

 

 

200 secs

 

140 + 10

 

150 + 10

 

 

160 + 10