We are never quite sure how these myths get started, but my team and I hear some doosee’s from time to time. The “myth” I am going to discuss today is one we actually see more often than not. We see this even in facilities that have a good grasp of their Hazardous Locations and of course we see it most often in facilities that are struggle with classifying thier hazardous location. I have a Class I Division 1 HAZLOC…what type of forklift am I allowed to operate within this hazardous environment?
First lets define the different hazard classification for flammable gas/vapor atmospheres:
Class I, Division 1 is a location:
(i) In which ignitable concentrations of flammable gases or vapors may exist under normal operating conditions; or
(ii) In which ignitable concentrations of such gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or
(iii) In which breakdown or faulty operation of equipment or processes might release ignitable concentrations of flammable gases or vapors, and might also cause simultaneous failure of electric equipment.
Note to the definition of “Class I, Division 1:” This classification usually includes locations where volatile flammable liquids or liquefied flammable gases are transferred from one container to another; interiors of spray booths and areas in the vicinity of spraying and painting operations where volatile flammable solvents are used; locations containing open tanks or vats of volatile flammable liquids; drying rooms or compartments for the evaporation of flammable solvents; locations containing fat and oil extraction equipment using volatile flammable solvents; portions of cleaning and dyeing plants where flammable liquids are used; gas generator rooms and other portions of gas manufacturing plants where flammable gas may escape; inadequately ventilated pump rooms for flammable gas or for volatile flammable liquids; the interiors of refrigerators and freezers in which volatile flammable materials are stored in open, lightly stoppered, or easily ruptured containers; and all other locations where ignitable concentrations of flammable vapors or gases are likely to occur in the course of normal operations.
Class I, Division 2 is a location:
(i) In which volatile flammable liquids or flammable gases are handled, processed, or used, but in which the hazardous liquids, vapors, or gases will normally be confined within closed containers or closed systems from which they can escape only in the event of accidental rupture or breakdown of such containers or systems, or as a result of abnormal operation of equipment; or
(ii) In which ignitable concentrations of gases or vapors are normally prevented by positive mechanical ventilation, and which might become hazardous through failure or abnormal operations of the ventilating equipment; or
(iii) That is adjacent to a Class I, Division 1 location, and to which ignitable concentrations of gases or vapors might occasionally be communicated unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided.
Note to the definition of “Class I, Division 2:” This classification usually includes locations where volatile flammable liquids or flammable gases or vapors are used, but which would become hazardous only in case of an accident or of some unusual operating condition. The quantity of flammable material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that merit consideration in determining the classification and extent of each location.
Piping without valves, checks, meters, and similar devices would not ordinarily introduce a hazardous condition even though used for flammable liquids or gases. Locations used for the storage of flammable liquids or liquefied or compressed gases in sealed containers would not normally be considered hazardous unless also subject to other hazardous conditions.
Once we have properly designated our workspace, we then have to determine what type of forklift (or pallet jack) is allowed to operate in our hazardous locations. We turn to 1910.178(c)(2) for guidance on this and it states:
REMEMBER, there are combustible dusts in workplaces and their are REQUIREMENTS for these workplaces as well, BUT I am only going to cover Class I locations (gases/vapors) in this discussion.
(emphasis added by me) 1910.178(c)(2)(iii) ONLY approved power-operated industrial trucks designated as EX may be used in atmospheres containing acetone, acrylonitrile, alcohol, ammonia, benzine, benzol, butane, ethylene dichloride, gasoline, hexane, lacquer solvent vapors, naphtha, natural gas, propane, propylene, styrene, vinyl acetate, vinyl chloride, or xylenes in quantities sufficient to produce explosive or ignitable mixtures and where such concentrations of these gases or vapors exist continuously, intermittently or periodically under normal operating conditions or may exist frequently because of repair, maintenance operations, leakage, breakdown or faulty operation of equipment.
The question we always get is…how much flammable liquid do I have to have to meet the scenario above. The answer is…and you’re going to love it – IT DEPENDS! It depends on the size of the room or enclosed workspace, the container(s) in which your flammable liquids or vapors are contained in, how many containers are allowed in the work area, the properties of the materials, etc.
For example, here are three sceanrios:
#1 – a really large warehouse that stores pallets of sealed containers of flammable liquids in 16 oz. containers is most likely not going to have any Hazardous Locations and there will be no restrictions for the type of forklift based on hazardous atmospheres.
#2 – On the other hand, we have the same warehouse but in the back corner the warehouse there is a maintenance area and in this area the business stores four drums of xylene they use for cleaning parts and other infrequent uses. Now things have changed considerably. As soon as we walked into the area we could smell the xylene, three of the drums were bung top drums and had both bungs off on all three of the drums and the fourth drum was an open top drum they used as a “solvent bath”. All four drums were stored right next to the steam radiator, and even though it was 20 degress outside, the solvent temperature was 74 degrees. This may sound like splitting hairs, but this set up just made this area a HAZLOC, still have to decide if it will be a Div 1 or Div 2. I am leaning towards Div 1 which would mean only EX would be allowed. But keep in mind, this is their forklift repair shop! The easiest thing to do would be to REDUCE the number of drums in the area and STOP storing them next to th heater! I would also recommend using bung top drums and a hand pump when they need to exract solvent for use and to keep the drums CLOSED when not in use. Taking ALL of these actions would allow the business to treat this area as an ordinary area and no restrictions on what type of truck could enter the area. But if they did not want to make the changes, and they rated it Div 2, then the only type of forklifts and pallet jacks that would be allowed would be DY, EE, or EX.
#3 – a processing area where solvents are processed/stored in the area in large vessel. The area has a lot of piping, valves, pumps, meters, etc. as a processing area would have. The area is classified as a Class I Div 1 area due to the process being atmospheric and always having vapor present in the work area. No arguement this is a Div 1 location, so ONLY a DX is allowed as stated in (c)(2)(iii). What if the business installed a properly designed ventialtion system that would ensure no more than 25% of an LEL would be achieved in the area? This would allow them to reclass the area to ordinary occupancy. NOTE: Check your local fire and HAZMAT codes as many states and local juridictions require the ventialtion system be on an independent back-up power. With the proper ventialtion system the business could take any type of truck into the area since it would be classified as an “ordinary area”.
The critical path in making the decision on the type of truck that can operate in a particular area is to FIRST make the proper determination of the area’s hazardous location classification. Once this has been established, using 1910.178 is quite easy.
The last kicker I wish to point out is the use of 1910.178(c)(2)(v). Too many poeple read this as an “exception to the standard” and OSHA NEVER intended this paragraph to be used in this manner. What (c)(2)(v) is saying is what I presented above about how one goes about classifying a hazardous location. It is meant to aid in the analysis the likelihood of a single event causing a flammable atmosphere. Let’s break down (c)(2)(v)…
In locations used for the storage of hazardous liquids in sealed containers or liquified or compressed gases in containers, approved power-operated industrial trucks designated as DS, ES, GS, or LPS may be used. This classification includes locations where volatile flammable liquids or flammable gases or vapors are used, but which, would become hazardous only in case of an accident or of some unusual operating condition. The quantity of hazardous material that might escape in case of accident, the adequacy of ventilating equipment, the total area involved, and the record of the industry or business with respect to explosions or fires are all factors that should receive consideration in determining whether or not the DS or DY, ES, EE, GS, LPS designated truck possesses sufficient safeguards for the location. Piping without valves, checks, meters and similar devices would not ordinarily be deemed to introduce a hazardous condition even though used for hazardous liquids or gases. Locations used for the storage of hazardous liquids or of liquified or compressed gases in sealed containers would not normally be considered hazardous unless subject to other hazardous conditions also.
The key here is the area is used for STORAGE and ALL containers are SEALED. The principal here is that there is little chance for a flammable atmosphere to form in the area where the forklift would be operating, as an accident would have to impact many of the small containers rather than just one large container like what would be found in an atmospheric processing area. All the areas I have highlighted above are basically the same considerations you are making when you make the call as if the area will be a Div 1 or Div 2 area, so this really is NOT some type of exception to take any type of truck.