Types of hazards - signs | NZ Transport Agency Waka Kotahi

The types of environmental hazards are:

vertical alignment – dips, humps, and uneven surfaces Table 6‑17 describes the signs that should be used at dips, humps and uneven surfaces. For further information refer to the Speed management guide;
Table 6‑17
Speed management guide
road surface - Table 6‑18 describes the signs that should be used for sites with slippery surfaces. Consideration should be given to covering or removing these signs when conditions are not as extreme such as during summer months. Slippery surface signs should be removed when the surface condition changes (resealing, improved skid resistance) and no longer constitutes a hazard;
Table 6‑18
slips, falling debris, and flying stones –Table 6‑18 describes the signs that should be used for sites with Slips, falling debris, and flying stones; and
water crossings – fords and areas prone to flooding - Table 12‑4 describes the signs that should be used for sites with water crossing or areas prone to flooding.
Table 12‑4

For specific sign details such as size and symbol height refer to sign specifications.

Sign specifications

Table 6‑17: Traffic signs for vertical alignment hazards

Sign code	Example	Description/use
W14-3 Sudden dip		Should be installed where in the opinion of the RCA, a sharp dip in the profile of the road is likely to cause considerable discomfort to road users, to cause shifting of a load, or to deflect a vehicle from its course and cause loss of control when crossed at speed. Should not be used to warn of inadequate sight distance for overtaking manoeuvres. For sign location refer to note 1.
W14-4 Hump		Should: be installed where in the opinion of the RCA, a hump (sharp rise) in the profile of the road is likely to cause considerable discomfort to road users, to cause shifting of a load, or to deflect a vehicle from its course and cause loss of control when crossed at speed; and be installed for the first hump after every intersection where a series of humps are installed. Depending on the spacing of humps, additional hump signage may be required between intersections (refer to Speed Management Guide). Should not: be used to warn of inadequate sight distance for overtaking manoeuvres; and have any other sign other than W12-3.2 Curve sign supplementary – advisory speed attached to it. For sign location, refer to note 2.
W14-5 Uneven surface		Should be installed where in the opinion of the RCA, road surface causes a hazard For sign location, refer to note 1.

Sign code

Example

Description/use

W14-3

Sudden dip

Should be installed where in the opinion of the RCA, a sharp dip in the profile of the road is likely to cause considerable discomfort to road users, to cause shifting of a load, or to deflect a vehicle from its course and cause loss of control when crossed at speed.

Should not be used to warn of inadequate sight distance for overtaking manoeuvres.

For sign location refer to note 1.

W14-4

Hump

Should:

be installed where in the opinion of the RCA, a hump (sharp rise) in the profile of the road is likely to cause considerable discomfort to road users, to cause shifting of a load, or to deflect a vehicle from its course and cause loss of control when crossed at speed; and
be installed for the first hump after every intersection where a series of humps are installed. Depending on the spacing of humps, additional hump signage may be required between intersections
(refer to Speed Management Guide).

Should not:

be used to warn of inadequate sight distance for overtaking manoeuvres; and
have any other sign other than W12-3.2 Curve sign supplementary – advisory speed attached to it.

For sign location, refer to note 2.

W14-5

Uneven surface

Traffic signs which displays two humps icon on diamond yellow background

Should be installed where in the opinion of the RCA, road surface causes a hazard

For sign location, refer to note 1.

Table 6‑17 notes:

The sign should be installed so as approaching drivers have an uninterrupted view of it over a distance of at least 120m in rural areas and at least 60m in urban areas.
When used in conjunction with speed control road humps, the sign should be located adjacent to the hump and located where approaching drivers have an uninterrupted view of it over a distance of at least 60m.

Table 6‑18: Signs for road surface hazards

Sign code	Example	Description/use
W14-7 Slippery Surface		Should only be used in conjunction with W14-7.1, W14-7.2, or Wa4-7.3 signs. Should not be installed separately. For sign location, refer to note 1.
W14-7.1 Supplementary – slow when frosty		Should be used in advance of short sections of road where in the opinion of the RCA, ‘local climatic conditions’ cause ice to form on the road at greater than is general in the locality; Where several such sections of road occur in close proximity, an RCA may use additional supplementary W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs for the route along with W14-7.1. Separate W14-7.1 signs may be used within the overall length to highlight particularly hazardous local areas No other sign other than W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs may be attached to the W14-7.1 sign combination or its support. The W12-3.1 sign is installed 100mm below the W14-7.1 sign. For sign location, refer to notes 1 and 2.
W14-7.2 Slippery surface when wet		Should be: used in advance of short sections of road where in the opinion of the RCA, the nature is such that it is unsafe to travel at a speed more than 10km/h below dry weather operating speed; and removed as soon as the road surface defect is remedied. Should not be used where the hazard is of a temporary nature or due to road works. The W3-2 Slippery surface sign should be used instead. No other sign may be attached to the W14-7.2 sign or its support. For sign location, refer to notes 1 and 2.
W14-7.3 Supplementary gravel road		Should be: used in advance of sections of road where the road is unsealed; removed as soon as the road is sealed; and used in conjunction with W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs where the gravel road extends for only a short distance, typically 5km or less. Should not be used on a sealed road in advance of a turn off to an unsealed road. For sign location refer to notes 1 and 2.
W14-6 Slips/falling debris		Should: be installed in accordance with sections of road where experience has shown that a slip or slips occur at unusually high frequencies. When slipping occurs only occasionally then the W3-1 temporary sign should be used; be installed in advance of section of road where in the opinion of the RCA, loose stones, vegetation or other debris may be expected to be encountered on the roadway following adverse weather; and show the symbol orientated in the same direction the rocks would fall towards the road sign. For sign location, refer notes 1 and 2.
W14-7.4 Gravel road		Should be installed in rural areas in advance of permanent unsealed sections of a main route where in the opinion of the RCA it is unsafe to travel on the gravel surface at the operating speed of the adjoining sealed section because of the potential for vehicles to lift loose stones and create a hazard for oncoming traffic. For sign location, refer notes 1 and 2. Can be used in conjunction with W14-7.3 Supplementary gravel road sign.
W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs		May be installed in conjunction with the other signs in this table where the hazard extends over a length of 800m or more. Must only be used as a supplementary plate to another permanent warning sign. The number may be varied to the appropriate length of the hazard. The sign may be repeated at intervals along the hazardous section of road at a maximum interval of 5km.

Sign code

Example

Description/use

W14-7

Slippery Surface

traffic sign which displays a car slipping icon on diamond shape yellow background

Should only be used in conjunction with W14-7.1, W14-7.2, or Wa4-7.3 signs.

Should not be installed separately.

For sign location, refer to note 1.

W14-7.1

Supplementary – slow when frosty

Traffic sign which says slow when frosty on square yellow background

Should be used in advance of short sections of road where in the opinion of the RCA, ‘local climatic conditions’ cause ice to form on the road at greater than is general in the locality;

Where several such sections of road occur in close proximity, an RCA may use additional supplementary W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs for the route along with W14-7.1.

Separate W14-7.1 signs may be used within the overall length to highlight particularly hazardous local areas
No other sign other than W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs may be attached to the W14-7.1 sign combination or its support. The W12-3.1 sign is installed 100mm below the W14-7.1 sign.

For sign location, refer to notes 1 and 2.

W14-7.2

Slippery surface when wet

Traffic sign which says slow when wet on square yellow background

Should be:

used in advance of short sections of road where in the opinion of the RCA, the nature is such that it is unsafe to travel at a speed more than 10km/h below dry weather operating speed; and
removed as soon as the road surface defect is remedied.

Should not be used where the hazard is of a temporary nature or due to road works. The W3-2 Slippery surface sign should be used instead.

No other sign may be attached to the W14-7.2 sign or its support.

For sign location, refer to notes 1 and 2.

W14-7.3

Supplementary gravel road

Traffic sign which says gravel road on rectangular yellow background

Should be:

used in advance of sections of road where the road is unsealed;
removed as soon as the road is sealed; and
used in conjunction with W12-3.1 Curve sign supplementary – next ‘[distance]’ km signs where the gravel road extends for only a short distance, typically 5km or less.

Should not be used on a sealed road in advance of a turn off to an unsealed road.

For sign location refer to notes 1 and 2.

W14-6

Slips/falling debris

Traffic sign which displays side of a mountain with falling debris icon on diamond shape yellow background

Should:

be installed in accordance with sections of road where experience has shown that a slip or slips occur at unusually high frequencies. When slipping occurs only occasionally then the W3-1 temporary sign should be used;
be installed in advance of section of road where in the opinion of the RCA, loose stones, vegetation or other debris may be expected to be encountered on the roadway following adverse weather; and
show the symbol orientated in the same direction the rocks would fall towards the road sign.

For sign location, refer notes 1 and 2.

W14-7.4

Gravel road

Traffic sign which displays 2 cars icons where one car is hitting the other with loose gravel

Should be installed in rural areas in advance of permanent unsealed sections of a main route where in the opinion of the RCA it is unsafe to travel on the gravel surface at the operating speed of the adjoining sealed section because of the potential for vehicles to lift loose stones and create a hazard for oncoming traffic.

For sign location, refer notes 1 and 2.

Can be used in conjunction with W14-7.3 Supplementary gravel road sign.

W12-3.1

Curve sign supplementary – next ‘[distance]’ km signs

Traffic sign which says next 5 km on rectangular yellow background

May be installed in conjunction with the other signs in this table where the hazard extends over a length of 800m or more. Must only be used as a supplementary plate to another permanent warning sign. The number may be varied to the appropriate length of the hazard. The sign may be repeated at intervals along the hazardous section of road at a maximum interval of 5km.

Table 6‑18 notes:

The sign should be installed so as approaching drivers have an uninterrupted view of it over a distance of at least 120m in rural areas and at least 60m in urban areas.
Should be installed in advance of the hazardous section by at least the distance shown in the table below.

Operating speed	Distance
50km/h	65m
70km/h	100m
80km/h	120m
90km/h	140m
100km/h	160m

Online services

Types of hazards - signs