HHSRS VERSION 2

Vulnerable age

Related hazards

All ages

Multiple locations

Uncombusted gas: Carbon Monoxide etc Secondary hazards

EXPLOSIONS

Yes

No

Yes

No

A) Gas fire to ground floor front room

Front elevation

[Main photo stretched to fit exactly between

lines}

Rear elevation

Rear elevation

DESCRIPTION OF HAZARDS

Dwelling:

1920s semi-detached house

A)

Gas pipe and fire: The gas fire fitted into the open fireplace in the front living room is old and

obsolete. The joint between the fire and the opening is unsealed. However, more relevant is that the

movement of the gas fire has loosened the joint between the pipe and the gas tap. There is no

permanent means of ventilation to the room. Neither the fire nor the gas installations have been

checked or serviced over the last five years.

LIST OF RELEVANT MATTERS

LIKELIHOOD

A

# Secondary hazards

A

a

Unauthorised gas supply

-

-

None

-

b

Siting of gas tanks

-

c

Gas installations - defects

3

d

Gas appliance - defects

3

e

Maintenance defects

3

f

Ventilation

3

g

Gas storage

-

h

Hot water storage tanks

-

i

Vented hot water system

-

Key

3

Seriously defective

1 Not satisfactory

j

Unvented hot water system

-

2

Defective

- Satisfactory/NA

A B C D E F G H

I

J

Average likelihood, outcomes and HHSRS score for hazards from explosions for all persons

in 1920-45 houses and all dwellings, 1997-99

Score

18

HEALTH AND SAFETY RATING SYSTEM SCORES

1920-45 house

1 in

32

LIKELIHOOD

Low

High

Average: 159,528

Example

32

< 4200 2400 1300 750 420 240 130

75

42

24

13

7.5

4

2.5

1.5 >

Justification

OUTCOMES

Class I

Class II

Class III

Class IV

Justification

RATING

Whether or not the fire is in use, there is a significant likelihood of uncombusted gas

leaking into the room. With no means of permanent ventilation (particularly at high level)

the gas will accummulate within the room. A spark from a light switch or electric socket,

or a lighted match would be sufficient to cause an explosion. On the otherhand, it is

likely that the smell of gas would alert most people to the problem first and this has been

taken into account when determining the likelihood.

%

Average: 11.2

10.0

< 0.05 0.15 0.3

0.7

1.5

3

7

15

26

38 >

Av: 0.0

0.0

< 0.05 0.15 0.3

0.7

1.5

3

7

15

26

38 >

Av: 5.4

4.6

< 0.05 0.15 0.3

0.7

1.5

3

7

15

26

38 >

Av: 83.4

85.4

IMPROVE

Justification

NEW RATING

Av: Nos

10.0

0.0

4.6

85.4

< 0.05 0.15 0.3

0.7

1.5

3

7

15

26

38 >

There is nothing to suggest that the harm outcomes will differ from the average

Example

B

Average: 1

C D E F G H

I

J

A

3194

Score

RATING SCORES AFTER IMPROVEMENT

Likelihood to

1 in 5,600

Outcomes to

10.0 0.0

4.6 85.4 %

The gas installations and this gas fire (and any other gas appliances) should be properly

tested and any works carried out. This would probably include renewal of the fire and of

the pipe work. In addition, permanent means of ventilation (at high level) should be

installed. These works would bring the likelihood to the average.

Improved