There are 463 registered businesses from the tertiary sector in 2016 which are engaged in trade, transportation, finance and business service, and community, social and personal services. Majority of these establishments are wholesale and retail stores selling various kinds of merchandise including meat, fish and vegetable dealers. There are also service shops, eateries, bakeries, food processors, drugstores, and amusement centers and video shops. Buying stations are found along M. L. Quezon Street where copra, palay and abaca are traded. Agricultural supplies, automotive parts dealers, appliance dealers and gasoline/refilling stations are also thriving. Trading and business transaction in Irosin are concentrated mainly at the Central Business District (CBD) in the town continue reading : Commerce and Trade
In terms of marital status of the population 20 years old and over in 2007, there are 4,841 single or 20.2% of the total population of the age range which is 24,016. There are more single males than females with a ratio of 183 males per 100 females. Sixty percent of those 20 years old and over is married, 8.2% is widowed, 1.6% is divorced/separated, 9.8% is common-law/live-in and 0.2% is of unknown marital status.
The environmentally critical areas in the municipality under Presidential Proclamation No. 2146 are the NIPAS areas, timberlands, areas that are prone and vulnerable to natural hazards, areas with critical slopes, areas classified as prime agricultural lands and water bodies.
Historical and current extreme weather/climate event that have affected the municipality include El Nino-related droughts and La Nina- related floods. Irosin is also is exposed to tropical cyclones and associated maximal values of 24-hour rains and winds, particular during the northeast monsoon season from October to February. From the period 1948 to 2006, there were 33 tropical cyclones that crossed the Province of Sorsogon or an average of one tropical cyclone every two years. For the same period, the number of tropical cyclone which crossed the province and 100 kilometers from boundaries was 140 tropical cyclones or an average of five every two years. One of the most intense tropical cyclone continue reading : Current and Future Climate Risk
The risk areas in the municipality are the slopes of Bulusan Volcano, the riverbanks, the catchment basin of Cadac-an River and the hills and mountains with steep slopes.
The protected area or NIPAS area in the municipality is the Bulusan Volcano Natural Park located at barangay Cogon with an area of 1,045.71 hectares. The BVNP consists of montane and lowland forest in a mountain complex covering the municipalities of Irosin, Juban, Casiguran, Barcelona and Bulusan with a total area of 3,673.29 hectares. Biodiversity profile of the BVNP includes threatened bird species of Philippine Duck, Philippine Hawk-eagle, and Flame-breasted Fruit-Dove as well as restricted-range bird like Luzon Bleeding-Heart, Luzon Hornbill and others. Mammals that have been recorded include Philippine Brown Deer, Philippine Warty Pig and the threatened Giant Cloud Rat. Endemic herpetofauna include forest frogs, tree skinks and the continue reading : Environmental Conditions