Identifying potential confined spaces in and around the dairy, and having procedures in place to reduce the risk if we have to work in them.

Areas in the dairy, such as milk vats and silos, have the potential to be confined spaces.

Confined spaces are usually rooms or containers that are large enough for people to enter but have insufficient ventilation to allow in enough oxygen for someone to breath adequately. This introduces the risk of suffocation and death, particularly if hazardous chemicals are being used. People have been engulfed and killed by the contents of grain silos.
Confined spaces can have narrow, tiny or inconveniently located access hatches that make them difficult to enter and exit, particularly during an emergency.
The Confined Space Regulations will apply if an assessment of your silos or milk vats finds them to be confined spaces.
'Click here for Worksafe Victoria definition of a confined space.'

For the purpose of Australian Standard 2685 - Safe Working in Confined Spaces, a person whose head, i.e. the breathing zone or upper body, is inside a confined space is considered to have entered a 'confined space'. Inserting an arm, for example, into the confined space to test for air quality would not be classified as 'entering' a confined space.

In assessing your dairy for any confined spaces (including grain silos and milk vats), ask the following questions:

• Can the space be entered by any person?
• Does the space have a limited or restricted entry or exit that would make it difficult for a person to enter or exit?
• Will the space have a normal atmospheric pressure when someone is inside?
• Will the space contain:
• an atmosphere that has a harmful level of any contaminant; OR
• an atmosphere that does not have a safe oxygen level; OR
• any stored substance, except liquids, that could cause engulfment?

If you answer 'yes' to all four questions it is likely that your grain silo or milk vat is a confined space and the Confined Space Regulations apply. That assessment should be verified by your local WorkSafe authority.

MILK VATS

If you do not have to get into the vat or silo there are no confined space issues.
If you are unsure of the confined space status of your equipment, ask WorkSafe Victoria for a clarification. In Victoria, confined spaces are not determined just on the basis of working in a physically restrictive location, also considered are their design and the hazards associated with a set of defined circumstances, such as restricted entry or exit, hazardous atmospheres or the risk of being engulfed.

Only appropriately trained people should be allowed to enter and work in a confined space.
If it is necessary to inspect milk vats on a regular basis, try to do this from the outside.
If you are having trouble with high bacterial counts, consult with both the manufacturer of the milk vat and your chemical company about a solution that does not require you entering the milk vat.
It may be possible to sufficiently clean the inside of a milk vat using a pressure washer. This option has the advantage of not using any hazardous substances or other chemicals, although suitable PPE should be used, such as goggles and hearing protection.

If it is necessary to enter a milk vat or milk silo, you need to be sure there are no harmful contaminants inside, including residual chemicals or refrigerants (consult with you vat supplier and service technician).

General recommendations include:

• put a cold rinse through the vat and ventilate after the wash cycle, in accordance with the manufacturer's instructions;
• turn off and isolate all power to the vat before entry - a mechanism must be in place to make sure the agitator is electrically isolated before maintenance and cleaning (lockout and tag out procedures);
• always have a responsible second person on-site when someone is working inside a vat or milk silo - it needs to be someone who can see what is happening inside and is capable of implementing rescue procedures in the case of collapse or injury in the vat;
• use mechanical ventilation to vent the space when someone is inside;
• clean vats with a scrubbing brush and water, or pressure water;
• if using chemicals ensure they are not hazardous;
• increase the ventilation and flow of breathable air by using fans;
• maximise ventilation by ensuring that all the inspection hatches are secured when open - this will also allow quick access in an emergency and increase internal visibility; and
• do not work in the heat.

'Engulfment' means to plunge into and be immersed by material. Loose material such as grain can bridge over when the contents of a silo are emptied from below, leaving the top layer in place. This 'bridge' can collapse while a person is walking on it and then the grain engulfs them.

GRAIN SILOS

Do not enter silos that pose a risk of someone being engulfed by grain. Never walk on top of grain. In the past, the design of grain silos has caused grain blockages, difficulties in emptying and the risk of being engulfed by the contents. There was also usually no option but to enter the potential confined space to tackle these issues. If this is the case on your farm, you have a potential confined space. If so, the Confined Space Regulations apply. You may want to consider retrofitting a bottom entry or replacing the silo. Modern silos have steep cones that lessen the chance of grain build-up and many have a bottom entry hatch. This type of entry allows for cleaning and the inspection of empty silos without having to fully enter the space. If it is necessary to fumigate a grain silo, ensure that everyone working on the job knows and follows the re-entry period specified by the fumigant manufacturer or MSDS.

Due to the high risks involved with entering confined spaces, the Confined Space Regulations state that it is essential that you create a formal procedure for working in confined spaces, and that you and your workers follow it to the letter.

Your plan for working in confined spaces may include:

• a register of confined spaces on your dairy;
• a list of authorised people who are sufficiently trained and experienced to enter a confined space;
• a system of confined space entry permits;
• a risk management record; and
• an emergency response procedure.

Given the level of complexity involved in working in confined spaces, it may be more convenient to eliminate the risks to you and your workers by contracting a suitably qualified professional (contact your milk vat technician or supplier) to perform tasks within the milk vat or silo. They will, however, need to meet the requirements of the Confined Space Regulations This will not remove the existence of confined space hazards, but will reduce the risk by having an expert do the job.
It may not be feasible to contract out the servicing of existing milk vats, but when buying a new vat or silo, the manufacturer or seller may provide a maintenance contract as part of the purchase price, as is often the case with other dairy and farm equipment.

When buying a new or replacement milk vat or silo, select one that does not require physical entry - thus completely eliminating the confined space hazard.
Otherwise, consider using equipment that has a large hatch at or near ground level and does not require full entry into the space. Using hatches for inspection, rather than having to climb inside, reduces the risk of injury and harm considerably.

If it is necessary to enter confined spaces, you will have to satisfy the obligations of the:

• OHS (confined spaces) Regulations 1996;
• Victorian Code of Practice for Confined Spaces 1997; and
• Australian Standard 2865 - Safe Working in Confined Spaces 2001.

For that reason, it is recommended that a suitably qualified professional be used to service, repair or work within any of your potential confined spaces.

Code of Practice for Confined Spaces
  http://www.worksafe.vic.gov.au

Confined spaces
  http://www.worksafe.vic.gov.au

Code of Practice for Plant
  http://www.worksafe.vic.gov.au

Australian Silo Clean Pty Ltd
 http://www.australiansiloclean.com.au/

Better Health Channel
Farms - The danger of confined spaces
 http://www.betterhealth.vic.gov.au

Standards Australia
AS/NZS 2865:2001 - Safe working in a confined space
HB 213:2003 : Guidelines for safe working in a confined space
 http://www.standards.com.au