Specification for galvanized mild steel fire bucket
1974 Edition

The fire buckets must be fabricated from galvanized mild steel conforming to prescribed structural steel grades. The body is made from 1 mm thick galvanized steel sheets, formed in two halves joined through butt welding. The rim is reinforced with 3.55 mm diameter mild steel wire, uniformly beaded without gaps, and handles are crafted from mild steel rods or wires, free to rest along the bucket edge and firmly welded. This guarantees strength, corrosion resistance, and compliance with the 10-litre nominal capacity requirement.

The standard mandates a minimum zinc coating mass of 0.06 grams per square centimeter (both sides inclusive), which translates to approximately 84 microns thickness considering zinc's density. This coating thickness ensures effective corrosion protection in accordance with hot-dip galvanizing standards. Additionally, the bucket must be painted with two coats of white paint inside, two coats of red paint outside, and two coats of black paint on handles and ears to enhance durability.

To confirm watertightness, the bucket undergoes multiple tests: First, it is filled with water and held stationary for 15 minutes to check for leaks. Next, an immersion test involves pressing the empty bucket top-up into a water tank ensuring the rim is above the waterline, observing for water ingress. Lastly, an air bubble test is conducted by submerging the bucket top-down without agitation; any escaping air bubbles indicate leakage and failure. Passing these tests ensures the bucket is free from leaks and airtight.

The internal surface of the bucket must be coated with two layers of white oil-based paint conforming to IS 641-1964. The exterior requires two coats of fire red paint (shade number 536 as per IS 5-1978), using either oil paint IS 120-1962 or enamel finish IS 2932-1964. Handles and ears are to be painted with two coats of black oil paint as per IS 128-1962. This finishing ensures high visibility, durability, and adherence to the standard.

Handles and ears must be made from mild steel with specified dimensions: ears are formed from 2.8 mm thick steel sheets welded at the top with the flat head on the side, while the top and bottom handles are constructed from 10 mm diameter mild steel rods. The top handle ends are bent as per design requirements and securely welded to the body, and the bottom handle is welded to the bucket base with smooth grips free from sharp edges to ensure safety and durability.

Each bucket must have permanent markings stamped or embossed on its side indicating the manufacturer's name or trademark, the year of production, and the bucket's capacity. Markings should be deep enough to remain legible after galvanizing. Furthermore, the bucket may bear the ISI Certification Mark, signifying conformity to the standard and quality assurance under the ISI inspection system. The external paint finish must be fire red as per the specified shade to maintain compliance.

Lot conformity is assessed by randomly selecting samples from at least 10% of the packages, with a minimum of three packages included. The sample size and the permissible number of defective buckets depend on the total lot size, as outlined in a specified table. A lot is accepted if the number of defective units does not exceed the allowed limit; otherwise, it is rejected. This sampling plan aims to keep the acceptance of lots with more than 2.5% defectives at a minimum, ensuring effective quality control.